ADVERTISEMENTS. OVER 2500 MACHINES SOLD. REFRIGERATING CAPACITY of Machines in tons of ice melted per 24 hours is MORE THAN 57,000 TONS. Special Conipoimd Macliines for Hot Climates. LINDE BRITISH REFRIGERATION CO., LTJ)., 35, aUEEN VICTORIA ST., LONDON, E.G. Telegrams: "SEPARATOR, LONDON.' Telephone No. 1573. ADVERTISEMENTS. 23 Medals and Diplomas Awarded FREDK. JONES & CO.'S Silieate CottoD PATENT BRITISH-MADE OR "SLAG WOOL" For Refrigerating Chambers and COLD AIR STORES SLl'^...^ Absolutely Iinperishable and Fireproof. One incli thickness equal as a non-conductor to three of any other insulating material, and costs about fifty per cent, less. Full particulars and references, etc., on application to the Sole Manufacturers as above at SILICATE COTJON WOJ?)(S. )CENTI8)< JOWJi, LOJ^DOJ^, N.W. X Ill ADVERTISEMENTS. DE LA VERGNE PATENT REFRIGERATING AND ICE-MAKING SYSTEM. The Most EFFICIENT, RELIABLE, & ECONOMICAL SYST EM in the MAR KET. Sole Licensees for Great Britain, the Colonies and British Possessions, L.ST^ERNE&CO.^Ltd, London Ofiice-28, VICTORIA ST., WESTMINSTER. JYiagara Hall Real Ice Rinh MacMnery Supplied and Made hy L. Sterne §- Co., Ltd. Ice Plants by means of Agitation or Distillation. Refrigeration by Direct Expansion, Brine Circulation or Air Circulation. Sm'all Machines suitable for Retail Meat, Fish, Butter or Pro- vision Salesmen, Hotels, Clubs, and Country Mansions, &c. CATALOGUES FORWARDED ON APPLICATION TO INTENDING PURCHASERS. Tenders, and all requisite informatiofi, freely given. REFRIGERATING AND ICE-MAKING MACHINERY A. J. WALLIS-TAYLER, C.E., A.M.I.CE. High Holborn, AV.C, AND 77, Victoria Road, Kilburn, NAV., London. Machinery and Sanitary l'yP'^^^''''^J%'Z'r Surveys Expert Evidence, Uorkmg and other Drawings Technical Translations from or rnto Fl-ench or Spanish, &^c., &^c. Digitized by the Internet Archive in 2011 with funding from Boston Library Consortium IVIember Libraries http://www.archive.org/details/refrigeratingiceOOwall ■L- .»J5,.^., if - 1, ^ REFRIGERATING AND ICE-MAKING MACHINERY / DEscizrprivE treatise for the use of persons EMPLOYING REFRIGERATING AND ICE- MA KING INSTALLATIONS, AND OTHERS A. J. WALLIS-TAYLER, C.E. ASSOC. MEMB. INST. C. E. AUTHOR OF "sugar MACHINERY," "BEARINGS AND LUBRICATION," " THE SANITARY ^- ARRANGEMENT OF DWELLIxNG-HOUSES," ETC. ETC. SECOND EDITION, WITH ADDITIONS ^\^ LONDON CROSBY LOCKWOOD AND SON 7, STATIONERS' HALL COURT, LUDGATE HILL 1897 D. VAN NOSTRAND COMPANY, LONDON : PRINTED BY J. S. VIRTUE AND CO., LIMITED, CITY ROAD. PREFACE, The subject of the present volume is one which ought to be of interest to a very large number of readers, inasmuch as machinery and apparatus for the production of cold by arti- ficial means, in addition to its more legitimate uses for ice- making" and the preservation of provisions of a perishable nature, is now employed, and plays an important part, in many industries and manufactures. Notwithstanding this, however, with the exception of the scattered information comprised in the few interesting and valuable papers which have been con- tributed from time to time to the engineering and other insti- tutions and societies, and of the able descriptive articles which have appeared in the leading technical journals at more or less wide intervals, but little has been written treating generally of machinery of this class. The author is, therefore, led to hope thit a treatise dealing with the machinery and apparatus used in the principal systems of refrigerating and ice-making will prove not unuseful both to those employing, or intending to employ, and to those in charge of such machinery and apparatus, and to others who, whilst desiring to obtain information upon the subject, have neither the opportunity or the facility for obtaining it from the sources above referred to. i ; ^ ^ ^. Vlll PREFACE. In the execution of the present work every endeavour has been made to place the matter before the readers in a concise form, and to include therein as much and as recent information upon the subject as practicable, thus rendering the scope of the book as wide as possible, without unduly swelling its bulk or overstepping the limits of a publication capable of being pro- duced at a moderate cost. Simplicity and clearness of classi- fication and description have been also aimed at throughout. To render ihe work as valuable as possible for purposes of reference, the construction and arrangement of rooms and of cold stores and chambers for freezing and preserving pro- visions, and other manufacturing and industrial applications, and also the cost of working complete installations, have been gone into as fully as the space at command would allow; and to these have been added a chapter containing a short collec- tion of useful tables and memoranda pertinent to the subject. It is hoped that the end in view has been fairly attained, and that the book will be found of some service to those for whose use it is primarily intended. A. J. Wallis-Tavler. 124, Chancery Lane. London^ IV.C, 1895. PREFACE TO THE SECOND EDITION. But little more than a year having elapsed since the first edition of this work was placed before the public, no very material advance has since been made m the design of the class of machinery under consideration, and consequently no con- siderable alterations or additions to the book are called for. Some twenty pages of descriptive matter and as many illus- trations, however, relating to subjects of interest not dealt with, or not fully dealt with, in the previous edition, have been added, and a small part of the original matter has been re-written, and the illustrations replaced by views showing even more modern types of machines. That the object with which the book was written^ as set forth in the Preface to the first edition, has been fairly attained, so that the volume has met an actual demand for such a work, X PREFACE. is evidenced by the comparatively rapid sale and favourable reception of the first edition ; and the author trusts that the second edition may meet with a not less gratifying amount of success. A. J. Wallis-Tayler. 323, High Holboen, London, W.C., l?97. CONTENTS. Introduction CHAPTER I. CHAPTER H. The Utilisation of the more or less rapid Dissolution of a Solid to Abstract Heat, or the Liquefaction Process .... 7 CHAPTER HI. The Abstraction of Heat by the Evaporation of a Portion of the Liquid to be Cooled, the Process being assisted by an Aii'-pump, or the Vacuum Process r 2 CHAPTER IV. The Abstraction of Heat by the Evaporation of a Separate Refrige- rating Agent of a more or less Volatile Nature, which Agent is subsequently Restored to its Original Physical Condition by Mechanical Compression and Cooling, or the Compression Process 21 CHAPTER V. The Compression Process (continued) — Ammonia Machines • . 36 CHAPTER VI. Management of Ammonia Compression Machines . . , « 77 xii CONTENTS. CHAPTER VII. PAGE The Abstraction of Heat by the Evaporation of a Separate Refrige- rating Agent of a Volatile Nature under the Direct Action of Heat, which Agent again enters into Solution with a Liquid, or the Absorption Process. — The Binaiy Absorption Process. . . 93 CHAPTER VIII. The Abstraction of Heat by first Compressing Air or Other Gas, Cooling Same, and aflenvards Permitting it to Expand, that is first Appl}dng Heat in order ultimately to Produce Cold, or the Cold- Air System ii6 CHAPTER IX. Refiigeration . , , i. , . 144 CHAPTER X. Construction and Arrangement of Rooms and of Cold Stores and Chambers for Freezing and Preserving Provisions , . .161 CHAPTER XI. Various other Manufacturing and Industrial Applications . , .188 CHAPTER XII. Ice-maMng ,, ^ , . . . . « , , .208 CHAPTER XIII. Co=t of Worldng , , .^ '233 CHAPTER XIV. Useful Tables and Memoranda , , , . . . ,2^0 INDEX „ . 265 LIST OF ILLUSTRATIONS. FIG. PAGE 1. Sulphuric Acid Vacuum Freezing Machine . . o 13 2. Exhaust Pump for Vacuum Freezing Machine . . , 16 3. Rotating Exhaust Pump or Cyhnder . . ► . 17 4. Early Compression Machine . . . . . . 22 5. Ether Compression Machine 25 6. Apparatus for the Distillation of MethyHc Ether . . 27 7. MethyUc Ether Machine 28 8. Distributor for Methylic Ether Machine .... 29 9. Compressor with Liquid Piston for Treating the Gas in Two Stages -33 10. Suction Valve of Compressor for Treating the Gas in Two Stages ' .... 34 11. Outlet or Discharge Valve for Treating the Gas in Two Stages 34 12. Single-acting Vertical Pattern Ammonia Compression Machine, with Sealing, Lubricating, and Cooling Oil or Fluid . 41 13. Double-acting Vertical Pattern Ammonia Compression Machine, with Sealing, Lubricating, and CooHng Oil or Fluid 43 14. Complete Vertical Pattern Ammonia Compression Machine with Horizontal Corliss Engine, of 220 tons Capacity . 4^^ 15. Marine Type of Vertical Pattern Ammonia Compression Machine, with Horizontal Engine and Special Govern- ing Apparatus 45 16. Complete Installation of Refrigerating Plant on the Ammonia Compression Principle .... 47 xiv LIST OF ILLUSTRATIONS. FIG. lARH 17. Diagram taken from a Single-acting Ammonia Com- pression Machine without the Seahng, Lubricating, and Cooling Oil or Fluid 5-:! 18. Diagram taken from a similar Compressor, with the said Sealing, Lubricating, and Cooling Oil or Fluid . , 51 19. Diagram taken from a Double-acting Ammonia Com- pression Machine ^vith the Sealing, Lubricating, and Cooling Oil or Fluid . . . , . . 52 20. Single-actmg Ammonia Compression Machine, with Movable Safety Head or ReUef Valve . . . 53 21. Single-acting Ammonia Compression Machine with Im- proved Safety Head or Relief Valve . . . . 5 :} 22. Duplex Single-acting Vertical Ammonia Compression Machine with Intermediate Equalising Chamber . 59 23. SmaU Ice-making Plant on the Ammonia Compression System ......... 60 24. Double-acting Horizontal Ammonia Compression Machine and Compound Condensing Engine . , 61 25. Double-acting Horizontal Ammonia Compression Machine, arranged to be driven fi-om any convenient somce of Power . 62 26. Single-acting Vertical Ammonia Compression Machine driven by a separate Gas Engine .... 64 27. Pair of Double-acting Horizontal Compression Machines with Vertical Engines ...... 65 28. Small Horizontal Ammonia Compression . Machine, with the Ammonia Condenser located beneath . - . . 67 29. Marine Type of Horizontal Ammonia Compressor and Vertical Engine ....... 70 30. Horizontal Compression Machine, with Vertical Engine and Refrigerator, especially designed for Brewery Work 71 31. Marine Type of Horizontal Pattern Compression Machine 72 31a, 315. Tandem Pattern Compound Ammonia Compression Machine, with Intermediate Chamber for Sealing and Lubricating Fluid ...... 73> 7^ 31^:. Ammonia Machine, with Corrugated Brine Coolmg Battery 76 LIST OF ILLUSTRATIONS. XV FIG. rA.;» 31^. View showing Application of Ammonia Macliinc and Cor- rugated Brine Cooling Battery to Beef I'loom . Frontispiece 32. Expansion Cock or Valve of the Taper Spindle Type, with Screw Adjustment 80 33 — 35- Expansion Cock or Valve, with Wedge-shaped Discharge Aperture, and "Worm and Worm Wheel Adjusting Gearing 8r 36 Water-saving and Cooling Apparatus .... 82 37. Oil Separator or Collector 86 38. Ammonia Absorption Machine, mth Fire-heated Gene- rator 95 39. Improved Ammonia Absorption Machine, with Steam- heated Generator 109 40, 41. Ammonia Pump of the Double-acting Piston Type, for Use with Ammonia Absorption Machint . . . in 4Ta — 41^. Apparatus for Working on the Intermittent Ammonia Absorption Process iljf — 113/ 42, 43. Cold-air Machine of the Horizontal Type, with separate Expansion Cyhnder 120, 121 44. Cold-air Machine of the Horizontal Type, with Single Cylinder, Compression taking place at one Side of the Piston, and Expansion at the other . . .122 45. Single-acting Cold-air Macliine of the Vertical T5^e, with Compression and Expansion Cylinders, Open at theii- Upper Ends 125 46. Horizontal Pattern Double-acting Cold-air Machine, with Compound Condensing Engine and Hollow Bed, form- mg Air-Cooler, &c. ■21 47. Diagonal Pattern Double-acting Cold-au- Machine and Hollow Bed, forming Air-Cooler, &c. . . .129 48. Vertical Pattern Double-acting Cold-air Machine, with Vertical Engine and HoUow Bed, forming Air Cooler, &c 130 49. Tandem Pattern Horizontal Cold-air Machme, with Double-acting Compressor, and Single-acting Ex- pansion Cylinders 134 50. Tandem Pattern Horizontal Cold-air Machine, ^vith Single-acting Compressor and Expansion Cylinders . 136 xvi IJST OF ILLUSTRATIONS. FIG. PArSR 51. Refrigerating Chamber, with Coohng Pipes arranged on the Brine Circulation System 148 51a. Refrigerating Chamber, with Corrugated Bottomed Tank for Coohng Purposes , i^od 52, 53. Compound Screwed and Soldered Joint for Ammonia Pipes 152, 153 54. Compound Flanged and Soldered Joint for Ammonia Pipes . . 154 55. Screw Coupling for Connecting together different lengths of Ammonia Pipes , , . . . . -155 56, 57. Stop Cocks or Valves for Ammonia Pipes . . 156, 157 58, 59. Disc or Gill for Increasing the Coohng Surface of Re- frigerating Pipes . . . . . . 158, 159 Co. Small Cold Storage Chamber, with Direct Gas-driven Cold-air Machine 1 74 61. Small Cold Storage Chamber, with Ammonia Com- pression Refrigerating JSIachine and Cooling Pipes on the Direct Expansion System 175 62. Beef Chill-room, with Refrigerating or Coohng Pipes on the Direct iCxpansion System, and fitted with Discs or Gills to Increase the Cooling Surfaces thereof . 176 63. Chill-room and Curing Cellar of Bacon Factor}', Re- frigerated on the Brine Circulation System . . 177 64. Hog Chill-room of Bacon Factory, Refrigerated with Pipes on the Direct Expansion System, fitted with GiUs or Discs and placed in a separate compartment provided in the Ceiling of the Main Room or Chamber . . 178 65. Small Marine Cold Store or Chamber for Passenger Steamer, Refrigerated by Cold-air Machine . . 179 66, 67. Method of Insulating, and An'angement of Refrigerating Pipes and Meat or Hanging Rails and Hooks, in Marine Cold Store 180, iSi 68. Method of Insulating Meat-carrying Chambers in Cargo holds of Steamers ....... 181 69. General Arrangement of Ammonia Compression Machines for Refrigerating Cargo Holds of Meat-carrying Steasaers 184 70. Arrangement of Ammonia Absorption Machine for Cool- LIST OF ILLUSTRATIONS. XVll via. PAGE ing Water for Refrigerating and Attennperating Purposes in Breweries 190 71. Fermenting Room of Brewery Refrigerated upon the Brine Circulation System 194 72. Fermenting Room of Brewery Refrigerated upon the Direct Expansion System, with Pipes fitted with Gills or Discs to Increase the CooHng Surfaces thereof 195 73. Arrangement of Apparatus for Extracting Solid ParafTm from Shale Oil by means of Refrigerating Machinery . 198 74. Arrangement of Ammonia Absorption Machine, for Use in Artificial Butter Works 200 75. Refrigerator for Cooling Water or other Liquid . . 202 76. Arrangement of Ammonia Compression Machine, for Use in a Dairy ... ...... 203 jGa—jGe. Gobert System of Shaft Sinking . . . 207a, 20'jb, 20'jc "J 'J. Ice-making Tank or Cistern, with Rotary Agitators, for ' Freezing or Congealing Clear or Transparent Pyramids of Ice . . .211 78. Can Ice-box or Tank, with Reciprocating Agitators, for Making Clear or Crystal Ice 213 79. Ice-making Tank or Box on the Wall or Plate System, with Reciprocating Agitators for Making Clear or Crystal Ice 216 80. Cell Ice-making Tank or Box, with Reciprocating Agita- tors arranged externally to the Spaces where the Blocks or Slabs of Ice are formed .... 220 80a — Sod. Ice-making Tank or Box, wdth Internally Cooled Chambers or Vessels Projecting into the Water . 221a, 221^ 80^. Arrangement for Making Ice on the Direct Expansion System 22 1^^ 81. Single-effect Distilling Apparatus for the Production of De-aerated Water for Making Clear or Crystal Ice without Agitation 223 82. Sextuple or Six-efFect Distilling Apparatus for the produc- tion of De-aerated Water in large quantities in extensive Ice Factories 225 83. Ice-tank or Box Room of Ice Factory, arranged on the Can System ........ 230 (Fo-'- Folding-Plates, see next 'pa^e.\ XVm LIST OF ILLUSTR AXIOMS FOLDING PLATES. Patent Refrigerating Machinery for Chilling Meat, with Ail' Circulating, Washing, Purifying, and Drying Apparatus facing fage 15c Patent 6-ton Ice-making and Refrigerating Plant, with Impro^'ed De-aerating Apparatus for making Pure Crystal Ice. Brine Circulation System . , . frd'^g fdg^ 232 REFRIGERATING AND ICEMAKING MACHINERY. CHAPTER I. Introduction. Although refrigerating and the production of ice by artificial means is said to have been known to, and practised by, the Ancients, it is only in comparatively recent times that improved systems and apparatus have enabled operations to be carried out profitably on a commercial scale, and have rendered possible the numerous manufacturing and industrial applications now made. In addition to their employment for the manufacture of ice, more durable, and — by reason of the known purity of the water congealed — more palatable and sanitary than the natural pro- duct ; to their extensive use for the freezing or chilling ot freshly killed meat in abattoirs ; and to their application to the cooUng of stores or chambers for the preservation of meat, fowl, fish, fruit, vegetables, and other provisions of a perishable nature : refrigerating machines are now commonly employed in a number of difi'erent manufacturing processes, a brief des- cription of the most important of which will be found in the chapter devoted to industrial applications. The trade in fresh provisions is one that during the last few years has made enormous strides, and at the present time vast quantities of frozen carcasses, and of fish, fruit, vegetables, and milk are being imported into this country. Space does not, unfortunately, admit of entering into any lengthy account of the history of this trade, which is one of great interest, or of indulging in statistics relative to the con- stantly increasing amounts of these imports; which figures can, B 2 REFRIGERATING AND ICE-MAKING MACHINERY. however, readily be got from a variety of sources by anyone interested therein, and which, moreover, hardly come within the province of a book purporting to be devoted to a descrip- tion of the various machines and appliances adapted for refrigeration and ice-making. The following, however, are a few of the leading facts : — The first cargo of frozen meat was brought to this country in the beginning of the year 1881, in the Sirathleven^ which is said to have been fitted with a Bell-Coleman cold-air machine, and this was quickly followed by another consignment in the Proios, refrigerated by means of a cold-air machine of the Lightfoot pattern. On October 5th of the same year the steamship Orient arrived at London with a cargo of frozen meat, she being also fitted with refrigerating apparatus on the cold-air principle, in this instance one of Haslam's patent dry^ air refrigerators being employed, which w'orSed" Withmir inter- ruption during 'the entire voyage of six weeks duration. On the 26th September in the succeeding year the clipper ship Matanra, also fitted with a Haslam patent cold-air machine, arrived with a cargo of frozen meat from New Zealand. Such were the commencements of the trade in refrigerated meat, and it has so rapidly advanced that, in mutton alone, from a few^ hundred carcasses in i88i it has risen to upwards of three millions in 1894, one million carcasses coming from Australia, and nearly one million four hundred thousand from the Argentine Republic. The total amount received in this country from the starting of the frozen meat trade up to the present date from all sources is twenty-six million carcasses of sheep and lambs, thirteen millions of which came from New Zealand, nine millions from the River Plata, three millions from Australia, one hundred and fifty thousand from the Falkland Islands, and the remaining eight hundred and fifty thousand from various other localities. In 1886 the steamship Nonpareil (Scrutton, Sons & Co.), which had been fitted for the purpose with a Haslam dry-air refrigerator, brought to this country the first cargo of West Indian fruit; and early in 1888 a cargo of apples was shipped from Melbourne in the Oceana, in chambers also cooled by a Haslam machine, both cargoes arriving in good condition. Since then many of the ships belonging to the Peninsular and Oriental Steamship Company, and others, have been fitted up for this trade. Within the last two years a considerable import trade in mi)k INTRODUCTION. 3 has also arisen ; one firm alone, during the past winter, having regularly sold 500 gallons of foreign milk daily, and thousands of gallons of foreign cream were likewise imported into this country within the same period, to be used for butter-making. The bulk of this milk is shipped to London from Gothenburg by steamer, having been frozen chiefly by refrigerating machines on the ammonia compression princinle, and costing, it is stated, 25 per cent, less than English milk. xA.ll these provisions can now be brought to this country in excellent condition, the chief dangers of deterioration being from hurried and consequently careless stowing, from bumps and bruises caused by rough and unskilled handling, and from exposure to higher temperatures during transit from the vessel to the cold stores on land, and subsequent distribution by road or rail to the retailers. To enable the following description of the several classes of refrigerating machinery to be clearly understood, it is absolutely necessary to be conversant with the usually accepted definitions of heat and the terms relating thereto, that have to be more or less frequently referred to in dealing with the subject. These definitions and terms will, no doubt, be perfectly familiar to most readers of this book, but everyone is liable at times to lapses of memory and doubt, and on such occasions it is found convenient to have the wherewithal to refresh it, and those, on the other hand, who are unacquainted with the subject will be saved the trouble of referring to other works in order to obtain the said definitions, and the meaning of the said terms. The principal terms that have to be used in treating of re- frigerating, and which will be met with in the following pages, are : — Thermal unit of heat (British), mechanical equivalent of heat, specific heat, and latent heat. The standard unit of heat used (thermal unit) in England is the heat necessary to raise the temperature of i lb. of water from 32° Fahr. by 1°, or that given up by i lb. of water in cooling 1° Fahr., viz., from 33° down to 32°. As to what heat really is. According to the accepted definition, heat i s motion, which theory was finally arrived at by Sir Hum- pHrey Davy iii 181 2, as the result of his observations of the ex- periments which he made in 1799, and of those of Benjamin Thompson (Count Rumford) in 1 798. In spite of this, however, it is extremely doubtful whether this is correct, or whether it is not as fallacious and misleading as numerous other scientific defi- nitions, the accuracy of which is usually taken for granted. 4 REFRIGERATING AND ICE-MAKING MACHINERY. The absolute truth upon the subject is that nothing, or next to nothing, is actually known for certain as to what heat really is. In a most interesting paper by Dr. Ernst Mach, Professor of Physics in the University of Prague, which appeared in the " Monist " of October, 1894, this deep and original thinker, after showing the absurdity of many universally accepted theories, remarks with reference to thermodynamics that, as it has been shown that heat is not a substance, the usually accepted theory is that it is a mode of motion, but Dr. Mach most con- clusively proves that this is not true. In an able article upon the fallacy of scientific definitions published in the "Engineer" of October 12th, 1894, the writer, after referring to the fact that the exact nature of heat is as yet absolutely unknown, truly observes that heat really behaves sometimes like a sub- stance and sometimes not. Joule's mechanical equivalent of heat equals 772 ft.-lbs^. That is to say that heat demands for its production, and produces by its disappearance 772 ft. -lbs. for each unit of heat. The experiments by which Joule determined the above equivalent were conducted by means of a falling weight, which actuated an agitator or paddle-wheel placed in water, the friction caused by a w^eight of i lb. falling though a distance of 772 ft., or of a weight of 772 lbs. falling through a distance of i ft., being found sufficient to heat i lb. of water i° Fahr. Specific heat is defined as being that amount of heat necessary to raise the temperature of a body of a given weight 1°. The unit of measure is that quantity of heat that is necessary in order to raise the same w^eight of water to an equal temperature. If equal weights of different bodies are raised the same number of degrees of temperature, each one takes up a different amount of heat, moreover, the specific heat of the same substance differs in accordance wdth its state, i.e., whether it be solid, liquid, or gaseous, and under varying con- ditions of temperature and pressure, increasing invariably with an increase of temperature or pressure. The specific heat of water is exceeded by but few bodies, and the variation thereof at different temperatures is so small as to be unworthy of notice. The specific heat of water is therefore taken as the standard of comparison, and at 32° Fahr. it is represented by unity. Latent heat, the existence of which was first discovered by Dr. Black in 176?, has been thus clearly and concisely defined by Balfour Stewart, in his "Treatise on Heat" : — " Latent heat INTRODUCTION. 5 is the heat which is absorbed by bodies in passing from one state to another, but it does not manifest itself by producing an increase of temperature, and is on this account called latent heat. ... A pound of water at 212°, mixed with a pound of water at 32°, gives 2 lbs. of water at 122°, the mean of the two components ; if, however, a pound of ice at 32° be mixed with a pound of water at 212*^, we have 2 lbs. of water at 51° only. . . . The difference being equal to that required to raise 2 lbs. of water through a range of 71° . . . representing the heat required to liquefy i lb. of ice." In addition to the above, calculations made with respect to heat will entail the use of the terms, absolute pressure and temperature. The first of these is pounds per square inch above a vacuum. Hence, as the zero" on a steam pressure ^auge represents atmospheric pressure it will be necessary to add 14' 7 lbs. to any particular gauge pressure to convert it into absolute power. Temperature is a term which implies that de- gree of sensible heat which a body possesses when compared with another body. The zero upon the thermometrical scale is an arbitrary zero or starting point, adopted because the real zero was unknown; recent experiments place it ar"46i° Fahr. Thus the absolute temperature of a body is that of absolute zero added to the ordinary thermometrical tempera-. Uire thereof For instance, if the latter be 32° Fahr. then the absolute temperature would be 493° Fahr., or 461 were it zero Fahr. on the thermometer. According to Boyle's or Marriotte's law the temperature remaining the same, the volume of any given quantity of gas will be in the inverse ratio to the pressure which it sustains. Finally it must be borne in mind that all substances contain, more or less, heat; and that as heat cannot be created, nor yet can it be destroyed, a body can only be reduced in temperature by the transference of more or less of its heat to another body. The abstraction of heat, therefore, from one body and its transfer to another, called the refrigerating or cooling agent, is naturally the main function of refrigerating and ice-making apparatus, and in order to insure continuity of action, the said refrigerating agent — the temperature of which must necessarily be lower than that of the substance upon which it is desired to act — must be either periodically renewed, or suitable means must be provided for the removal therefrom of the heat extracted or abstracted from the latter. That is to say, a continuously working machine comprises a heat-abstracting 6 REFRIGERATING AND ICE-MAKING MACHINERY. apparatus, and suitable means for automatically renewing at the requisite intervals the cooling agent or medium, or for the removal from the latter of the heat extracted from the body it is desired to cool, so as to enable it to be used over and over again in a continuous cycle. The various inventions for refrigerating and ice-making that are now in use, can be conveniently classified for the present purpose under the following five principal heads, viz. : — First, those wherein the more or less rapid dissolution or liquefaction of a solid is utilised to abstract heat. This is, strictly speaking, more a chemical process. Second, those wherein the abstraction of heat is effected by the evaporation of a portion of the liquid to be cooled, the process being assisted by an air-pump. This is known as the vacuum system. Third, those wherein the abstraction of heat is effected by the evaporation of a separate refrigerating agent of a more or less volatile nature, which agent is subsequently restored to its original physical condition by mechanical compression and cooling. This is called the compression system. Fourth, those wherein the abstraction of heat is effected by the evaporation of a separate refrigerating agent of more or less volatile nature under the direct action of heat, which agent again enters into solution with a liquid. This is termed the absorption system. Fifth, those wherein air or other gas is first compressed, then cooled, and afterwards permitted to expand whilst doing work, or practically by first applying heat, so as to ultimately produce cold. These are usually designated as cold-air machines. CHAPTER 11. The Utilisation of the more or less Rapid Dissolution of a Solid to Abstract Heat, or the Liquefaction Process. Liquefaction is one of the most ancient methods employed for artificial cooling. The reduction of temperature of water and other Hquids by the melting of saltpetre is said to have been known in India at a very remote period, and it is on record that one Blasius Villafranca, a physician of Rome, utilised it for this purpose as early as 1550. The Romans are said to have cooled wine by immersing the bottle containing the latter in a second vessel filled with cold water into which saltpetre was gradually thrown, whilst at the same time the said bottle was rotated rapidly. Freezing water by the use of a mixture of snow or powdered ice and saltpetre was mentioned by Latinus Tancredus of Naples in 1607, and wine by means of snow and common salt by Santorio in 1626. This was also in all probability the method employed by the Esthonian tribe for producing artificial cold, and freezing the dead, and liquids, as mentioned by Orosius about a.d. 400. . To this class belong the numerous ordinary and well-known] machines and apparatus employed for icing creams, lemonades,/ &c., which usually consist of a tub constructed of wood into] which a vessel containing the substance to be cooled or frozen is placed, and is surrounded by a frigorific agent, such as a mixture of pounded ice or snow and ciiloride of sodium; or a combination of certain chemicals may be substituted for the former. This method is also used on a more extensive scale for ice- making and cooling, but although ice can be produced on a commercial scale with improved apparatus, it is still more expensive than strictly mechanical methods. The best among the many forms of apparatus for making ice on this principle are probably those of Toselli and Siemens. 8 REFRIGERATING AND ICE-^IAKTNG MACHINERY. In Toselli's machine the frigorific agent consists of a mixture of ammonium nitrate and water, which produces a reduc- tion of temperature of about 40° Fahr. The apparatus requisite is one of extreme simpHcity, consisting merely of a vessel in which tlie solution of the salt is effected, and a can wherein are placed a number of moulds of different sizes, circu- lar in cross section, and formed with a slight taper. These moulds, previously filled with water, are inserted in the freezing mixture, and a thin film of ice is formed round their edges in a few minutes ; these slightly tapered tubes of ice are then withdrawn from the moulds, and placed one inside the other, thus forming a small stick of ice. The relative dimensions of the moulds are of course such as to form the ice tubes suitably proportioned to admit of the above operation. In Siemens' apparatus calcium chloride is employed as the frigorific agent. The dissolution of this salt in water produces a reduction of temperature of only about 30° Fahr., and to admit of this reduction being sufificient to produce ice with water at an initial temperature of 65° Fahr., a heat inter- changer is provided, wherein the spent liquor, which is at a temperature of about 30° Fahr., is employed to cool the water before it is mixed with the salt. It will thus be seen that there will be a gain in reduction of temperature equivalent to the amount of this cooling action. The salt can be re- covered by evaporation, and employed over and over again. This apparatus is stated to have worked well, producing ice on a large scale in a satisfactory manner, but owing to its being on the whole found to be inferior, and more costly than purely mechanical methods of producing ice, it has never come into general use. In an American machine, wherein ammonium nitrate is like- wise employed as the frigorific agent, cylindrical receptacles fitting cne within the other, so as to leave annular spaces or clearances, are provided. The water to be frozen is placed in the centre, the frigorific agent in the said annular spaces or clearances, so that the first or outermost acts to cool the second, the second the third, and the third the fourth, and so on, the cold being intensified at the centre in accordance with the number of the said annular spaces containing the frigorific agent. The series of cylindrical vessels or receptacles are arranged in a v/ooden outer casing so mounted as to be capable of being slowly revolved, and thereby promoting the more rapid disso- lution of the salt. This apparatus is analogous to that employed THE LIQUEFACTION PROCESS. 9 many years ago on a small scale for laboratory experiments by Walker, and by means of which he succeeded in sinking the spirit to —91° Fahr. When any of the above methods are employed for refrigerat- ing purposes, brine, previously cooled in the apparatus, is cir- culated in the usual manner through a system of cooling pipes. The general law governing the production of cold by frigo- rific mixtures is, that during the liquefaction of a solid, a certain amount of heat not indicated by or sensible to the thermo- meter is absorbed, which heat is abstracted from any sur- rounding bodies. The absorption of heat, consequently the production of cold, in the said environing bodies is the more marked in proportion as the sohd is more suddenly or rapidly liquefied. The following observations on frigorific mixtures are extracted from a paper''' on " Refrigerating and Ice-making Machinery and Appliances," by Mr. T. B. Lightfoot, C.E., M.I.C.E., who is a well-known authority upon the subject : " When a substance changes its physical state, and passes from the solid to the liquid form, the force of cohesion is overcome by the energy in the form of heat. The effect may be produced without change in sensible temperature, if the heat be absorbed at the same rate as it is suppHed from without. Thus, as is w^ell known, the temperature of melting ice remains constant at 32° Fahr., and any increase or decrease in the heat sup- plied merely hastens or retards the rate of melting without affecting the temperature. Mixtures of certain salts with water or acids, and of some salts with ice, which form liquids whose freezing points are below the original temperatures of the mix- tures, do not however behave in this way ; for under ordinary circumstances the tendency to pass into the liquid form is so strong, that the heat is absorbed at a greater rate than it can be supplied from without. The store of heat of the melting substances themselves is therefore drawn upon, and the tem- perature consequently falls until a balance is set up between the rate of melting and the rate at which heat is supplied from outside. This is what takes place with ordinary freezing mix- tures. The amount of the depression in temperature appears to depend to some extent on the state Otr hydration of the salt, and the percentage of it in the mixture. Almost the only salts used are those of certain alkalies, few others possessing the requisite solubility at low temperatures." * '* Proceedings, Institution of Mechanical Engineers," 1886, p. 201. 10 refrictErating and ice-making machinery Table of Principal Freezing Mixtures. Reduc tion of "0 j,^ temper iture in COMPOSITION OF FREEZING MIXTURES. degrees Fahr. 5 -'^ 2— - From To Snow or pounded ice, 2 parts ; muriate of soda i part - 5 Snow 5 ; muriate of sodium 2 ; muriate of am- monia, I — 12 Snow 24 ; muriate of sodium 10 ; muriate of am- monia 5 ; nitrate of potash 5 -18 Snow 12 ; muriate of sodimn 5 ; nitrate of am- monia 5 -25 Snow 4 ; muriate of lime 5 + 32 -40 72 Snow I ; chloride of sodium or common salt i , . + 32 32 Snow 2 ; muriate of lime crystallized 3 . . + 32 -50 82 Snow 3 ; dUute sulphuric acid 2 . . + 32 -23 55 Snow 3 ; hydrochloric acid 5 + 32 -27 59 Snow 7 ; dilute nitric acid 4 + 32 -30 62 Snow 8 ; chloride of calcium 5 + 32 —40 72 Snow 2 ; chloride of calcium ciystallized 3 4-32 -50 82 Snow 3 ; potassium 4 + 32 -51 83 Snow 2 ; chloride of sodium i — 5 Snow 5 ; chloride of sodium 2 ; cliloride of am- monia I — 12 Snow 14; cliloride of sodium 10; chloride of am- monia 5 ; nitrate of potassium 5 -18 Snow 12 ; cliloride of sodium 5 ; nitrate of am- monia 5 -25 Snow 2 ; dilute sulphuric acid i ; dilute nitric acid I . . — 10 -56 46 Snow 12 ; common salt 5 ; nitrate of ammonia 5 -18 "~ 25 Snow I ; muriate of lime 3 -40 — 73 33 23 Snow 8 ; dilute sulphuric acid 10 . . -68 -91 Chloride of ammonia 5 ; nitrate of potassium 5 ; water 16 + 50 + 4 46 Nitrate of ammonia i ; water i . . + 50 + 4 46 Chloride of ammonia 5 ; nitrate of potassium 5 ; sulphate of sodium 8 ; water 16 + 50 + 4 46 Sulphate of sodium 5 ; dilute sulphuric acid 4 . . + 50 + 3 47 Sulphate of sodium 8 ; hydrochloric acid 9 + 50 - 50 53 Nitrate of sodium 3 ; dilute nitric acid 2 + 50 - 3 Nitrate of ammonia i ; carbonate of sodium i ; water i . . Sulphate of sodium 6 ; chloride of ammonia 4 ; + 50 - 7 57 nitrate of potassium 2 ; dilute nitric acid 4 . . + 50 -10 60 Phosphate of sodium 9 ; dilute nitric acid 4 + 50 -12 62 Sulphate of sodium 6 ; nitrate of ammonia 5 ; dilute nitric acid 4 , . + 50 -14 64 THE LIQUEFACTION PROCESS. II Table of Principal Freezing MiXT-VK^s—Contmiied. COMPOSITION OF FREEZING MIXTURES. (Materials previously cooled.) nitrate of ammonia 3 nitrate of ammonia 2 Phosphate of sodium 5 dilute nitric acid 4 Phosphate of sodium 3 dilute mixed acid 4 Snow 3 ; muriate of lime 4 muriate of lime crystallized 2 . . muriate of lime 3 dilute sulphuric acid 3 ; dilute nitric 3 .• dilute nitric acid 2 dilute sulphuric acid i . , muriate of lime crystallized 3 . . Snow I ; Snow 2 ; Snow 8 acid Snow 3 ; Snow I ; Snow 2 ; Snow 8 ; dilute sulphuric acid 10 Reduc tion of 0) ,J3 temperature in degrees Fahr. From To -34 34 -34 + 20 -50 -48 16 68 -66 66 -15 -68 53 — 10 -46 46 46 -20 -60 40 -40 -73 3>1, -68 -91 23 CHAPTER III. The Abstraction of Heat by the Evaporation OF A Portion of the Liquid to be Cooled, THE Process being assisted by an Air-Pump, or the Vacuum Process. ' This class includes all such machines as operate to extract ^ heat by the evaporation or vaporization of a portion of the water or other liquid to be cooled or frozen. The cooling of liquids on this principle depends upon the conversion of the sensible heat into latent heat during evapora- tion, and, in its most primitive form, its use is almost coexistent with that of the world, having been commonly employed for refrigerating purposes in all ages. It is obvious, however, that as a portion of the liquid to be cooled is permitted to go to waste, it can be only profitably applied direct to liquids of liitle or no value, such as water. A common example of this method in its crudest form is found in the ancient plan, so universally adopted in hot climates, of cooling w^ater by the evaporation of a portion of the contents of a porous jar or vessel from the outer surface thereof, by hanging the said vessel in a position where it will be subjected to either a natural or an artificial draught. It is stated that the practice of procuring ice by exposing water to the night air in shallow porous vessels has been prac- tised in India during the cool season from the remotest ages. The said vessels are placed on a bed of straw, cornstalks, or megass (crushed cane stalks) in shallow excavations made pre- ferably in an exposed situation on an extensive plain, being filled with water to be congealed or frozen, and in the morn- ing, provided the night be clear, are found covered with thin crusts of ice. This process is also said to have been practised, both in THE VACUUM PROCESS. 13 France and in this country, in the latter part of the last century, with perfect success, so far at least as the production of ice was concerned, but it failed commercially by reason of the large expenses entailed. _ The first machine on the vacuum principle for the produc- tion of artificial ice by the conversion of sensible into latent heat by evaporation, of which there is any record, was that invented by Dr. Cullen, in 1755, who in that year made the discovery that the evaporation of water could be facilitated by the removal ot the atmospheric pressure by means of an air pump, to such a degree as to enable him to freeze water even in summer. This apparatus was the parent ot all those subsequently designed for cooling and congealing liquids by their own evaporation in vacuo, that is to say, wherein the vapour is drawn off from the partial vacuum wherein it is formed, and is condensed in another partial vacuum with or without the help of absorbents, and is expelled by pressure. In 1777, Nairne found that, by the introduction of sulphuric acid into a receiver for the exhaust, the aqueous vapour could be absorbed from the rarified air and the latter dried ; and by taking advantage of this discovery he was enabled, in 1810, to 14 REFRIGERATING AND ICE-MAKING MACHINERY. construct an apparatus wherein he got rid of the vapour that rose from the water, and thus prevented it from forming a per- manent atmosphere, and hindering the continuity of the operation. Further attempts were made by LesUe (1810), Vallance (1824), Kingsford (1825), and others, but without any much greater success attending their efforts, Edmond Carre's sul- phuric acid freezing machine being the first to be commercially successful. This apparatus, acting to refrigerate by evaporation and rari- fication, and which was adapted to produce the carafes frappes commonly used in Parisian cafe's and restaurants, consisted, as shown in Fig. 1, of a cylindrical vessel, a, intended to contain the charge of concentrated sulphuric acid ; an air- pump, B, so arranged that it could be connected to the mouth of the carafe, and of an agitator, c, which is so coupled to the air-pump lever that it will be operated during the working of the said pump in such a manner as to keep the sulphuric acid in the cyhndrical vessel a continually in motion. The machine of course only operates intermittingly, but the large body of sulphuric acid used in the vessel a prevents a rapid loss of absorptive power taking place through dilution, and the agitation obviates the formation of a more diluted stratum on the surface, which would be highly detrimental to the proper working of the apparatus. The chief drawback to this machine, besides its intermissive action, is the difiiculty experienced in maintaining the pump in good working order, and the various joints all perfectly gas tight. Franz Windhausen patented in 1878 a compound vacuum- pump designed to produce ice directly from water without using sulphuric acid \ and likewise a modified arrangement wherein sulphuric acid could be employed. In this latter apparatus the sulphuric acid is cooled by water whilst absorb- ing the vapour, and is subsequently concentrated, when it becomes over-diluted, thus obviating the necessity for the in- sertion of a fresh supply of acid. An improved foim of this machine constructed in 1881, nominally capable of producing from 12 to 15 tons of ice per 24 hours, and which was first put up at the Aylesbury Dairy, Bayswater, London, and afterwards removed to Bromp- ton, was fully described in a paper"^ written by Dr. Hopkinson. * " Journal of the Society of Arfr," 1882, Vol. xxxi., p. 20. THE VACUUM PROCESS. 1 5 The ice-forming vessels or moulds, which are six in number, are constructed of cast-iron, circular in transverse section, and slightly tapered. These cans, moulds, or cases moreover are steam-jacketed, so as to admit of the ice being melted or thawed off and readily disengaged therefrom, and are provided at their lower ends with hinged doors, which, when closed, form fluid-tight joints. The sulphuric acid is contained in a long cylindrical vessel wherein rotating agitators maintain the said acid in continual motion during the operation of the apparatus, and the said cylindrical vessel is water-jacketed so as to carry off the greater portion of the heat that becomes liberated during the absorp- tion of the vapour. The sulphuric acid cylinder or vessel communicates with the upper parts of the ice-forming vessels or moulds, and with the vacuum-pump, which latter has two cylinders, viz., a large double-acting one and a small single-acting one. The water is admitted to the moulds through nozzles at a regulated rate, the fine streams offering an extended surface for evaporation, and becoming instantly congealed into ice globules or particles, which, falling into the bottoms of the said moulds, are frozen, together with the water that collects there. In the operation ot the apparatus the air, and any vapour that may pass over from the sulphuric acid cylinder or vessel, are drawn into the large pump-cylinder, by which they are slightly compressed and passed on into the condenser, wherein a portion of the said vapour is condensed by cold water, the rest, together with the air, entering the second or smaller pump- cylinder, where they are compressed up to the tension of the atmosphere and discharged. This pump, it is stated, admits of a vacuum of half a millimetre of mercury being constantly maintained ; 2J mm., however, being as low a vacuum as it is found necessary to have during actual work. By the employment of a compound pump with an inter- mediate condenser, and performing the compression in two distinct stages, the losses that would otherwise occur from the clearance spaces in the large pump are greatly reduced. The concentrator for the diluted sulphuric acid consists in a lead-lined vessel or receptacle fitted with a steam-heated coil of lead piping and ccr,ne:ted with an ordinary air-pump. The acid is transferred from one vessel to the other by atmospheric /)re5sure, and the diluted or weak acid, which is a* a com- 1 6 REFRIGERATING AND ICE-MAKING MACHINERY. paratively low temperature, is heated on its way to the con- centrator in an interchanger, by the strong concentrated acid returning from the latter. The ice produced by this machine, like that of all those on the vacuum principle acting direct, is in an opaque and porous condition ; and the avoidance of this defect, and the produc- tion of clear transparent crystal ice by freezing it in moulds plunged in brine previously cooled by evaporation in a vacuum,* would render the process too expensive to be commercially successful. The total amount of water that is used in working is from lo to 12 tons per ton of ice, and the fuel i8o lbs. of coal to each ton of ice produced ; the latter is employed in raising the requisite supply of steam for driving the pumps, and heat- ing the coil in the sulphuric acid evaporator. Fig. 2 is a vertical central section partly in elevation showing Lange''s improved pump for exhausting the air from the ab- sorber of a vacuum machine. As will be seen from the draw- ing, three pistons, a, B, and c, are em- ployed, placed in line one above the other and working in three separate cylinders. The valves are so arranged that each of the uppermost cylin- ders draws from the one below, and they are sealed with oil, which latter con- stantly circulates through the pump. The mixed oil and air on leaving the top or uppermost cylinder is discharged into a separator d, the air being permitted to escape into the atmo- sphere, and the oil passing into a receptacle from which it can be returned to the pump when requir&d. The vacuum apparatus for the refrigeration of a liquid by Fig. 2. THE VACUUM PROCESS. 17 its partial evaporation, for which James Harrison took out a patent in 1878, is designed to produce opaque ice at a very low cost (about one shilling per ton), by reducing the fuel consumption, which, as already mentioned, is the chief item of expense. This is effected by getting rid of the bulk of the fric- tion engendered in the usual vacuum and air pumps, and also by a saving of the fuel expended in concentrating the weak or diluted sulphuric acid in the previously described apparatus. The main feature of Harrison's invention is the process of refri- gerating by the evaporation of the liquid to be cooled or con- gealed, by carrying its vapour under a head of neutral non- evaporable liquid, condensing the compressed vapour at the ordinary temperature, and removing the resulting liquid and air by a pump. One form of his apparatus consists in a rotating pump or cylinder which seems to provide a ready means of exhausting large volumes of low ten- sion vapour, without the expense of the labour en- t ailed in maintaining ordinary piston packings in an effective condition, and the great loss through friction therefrom. This device consists, as will be seen from the sectional diagramatical view. Fig. 3, of an iron cylinder, rotatably mounted hori- zontally upon hollow or tubular shafts or axles, and divided internally into different compart- ments by longitudinal ^1?- 3» partitions of an L shape in transverse section. This cylinder is connected through one of the hollow shafts or axles with the refrigerating or ice- making vessels or moulds, which may be of any convenient form, and it is partly filled with oil or other liquid, which latter must invariably be either non-evaporable or one which is only vaporizable at a temperature greatly in excess of that at which the refrigerating Hquid can be vaporized, and it must, moreover, be perfectly neutral chemically to the vapour with i6 REFRIGERATING AND ICE-MAKING MACHINERY. which it will be brought into contact when the machine is at work. The operation of the apparatus is as follows, viz. : — The cylinder rotates upon one of the fixed hollow axles, through which the vapour or gas to be compressed is delivered from the refrigerator or ice-making vessels, and the longitudinal partitions or compartments moving round with their apertures downwards carry with them charges of the vapour, and compress them to a degree varying in accordance with the depth to which they dip below the surface of the liquid. After attaining the lowest position the compressed vapour is liberated, and rises into a fixed hood or inverted channel, situated centrally and com- municating with the other hollow shaft or axle, which is placed at the other side of the cylinder, through which it passes to a surface condenser. In this surface condenser the compressed vapour is partially condensed, both by direct cooling action and also by the evaporation of water flowing over the surface, and the condensation water, together with any air present, are then compressed to the atmospheric tension and discharged. Several modifications are also described, viz. : — First, a series of buckets attached to endless chains dipping into a reservoir of the compressing liquid, and delivering the compressed gas or vapour into a reservoir. Secondly, a gasometer-shaped vessel, rising and fahing in an annular space filled with a non-evapor- able neutral liquid. The vessel, on being lifted, becoming filled with the air or vapour, and on being depressed delivering it under a head of liquid. Thirdly, a tapering archimedean screw working in a reservoir of non-evaporable neutral liquid by which the vapour is taken in at the larger upper orifices, and is dis- charged, compressed, and liquefied at the lower or smaller end. Fourthly, pumps with actuated valves and with arrangements for complete expulsion of air or vapour. And finally, fifthly, fans working in the air or vapour, and forcing it from one compart- ment into another, or exhausting it and forcing it into the atmosphere. A patent was obtained by Blyth and Southby some years back for a vacuum refrigerating machine of great simplicity of design. The main feature of their apparatus consists in the provision of two pumps, viz., a large main pump and a small auxiliary one, the former being heated by means of a steam jacket or other- wise. The large, single acting, steam-jacketed vapour pump, is driven by a crank, which is situated beneath, and is enclosed THE VACUUM PROCESS. ig in a suitable cylindrical casing or chamber, having at one side a door or cover admitting of access thereto, and so arranged that when closed it forms a gas-tight joint. The crank is driven by belt gearing, from any suitable source of motive power, and the pulley for the latter is fixed upon the end of a shaft or spindle passing through a stuffing box provided upon the opposite side, or wall, of the crank chamber, to that fitted with the said door or cover. A heavy balanced fly-wheel is also mounted upon the crank shaft, and is enclosed within the said chamber, which, as above mentioned, is made perfectly fluid tight. The ice box is fitted with an automatic feeding arrangement for filling the ice-can or case with water, which mechanism is operated by an eccentric upon the crank shaft, and the said box is connected with the pump through a pipe governed by a stop-cock or valve, a similar cock or valve being also fitted in the pipe leading to the cooling vessel, and another suitable valve in the vapour exit to the condenser. A double-acting air or ejector pump worked off the eccentric is moreover provided for removing the air from the interior of the machine, and a vacuum gauge for ascertaining the degree of vacuum produced. The operation of the machine is as follows, viz. : — Any air that may be contained within the large pump cylinder is first pumped or drawn off by the small air or ejector pump, thereby producing a vacuum which is filled by vapour from the water to be frozen or cooled. The large single-acting pump, v/hich draws the vapour from the said water through a suction valve situated in the piston, compresses the said vapour and delivers it through the outlet or discharge valve to the condenser, where it is condensed by water in the usual manner, is removed by the small air or ejector pump, together with any air that may have passed into the machine through leakage, and is dis- charged into the atmosphere. The vapour is prevented from condensing in the cylinder by the steam-jacket, which main- tains the temperature of the said cylinder above that at which the said vapour will condense into water. Were this not the case, and were the vapour permitted to condense in the cylin- der, the quantity to be discharged would be so small as not to be capable of being forced through the delivery or outlet valve. When starting the machine, communication between both ends of the vapour pump cylinder can be kept open for any 20 REFRIGERATING AND ICE-MAKING MACHINERY. requisite length of time during the first portion of the delivery stroke, so as to permit the air to return to the underside of the piston, and thereby lessen and regulate the expenditure of power required in getting up the vacuum. This is effected by means of a bye-pass and valve, which can be opened at starting, and kept open for about nine-tenths of the piston stroke, being closed gradually as soon as the vacuum becomes more perfect, and altogether as soon as all the air has been got rid of. The average pressure upon the piston is light, not exceeding about one-sixth of a pound. In all the above arrangements, a portion of the refrigerating agent itself, together with the heat it has absorbed, is rejected, consequently water, as the only one sufficiently inexpensive, is invariably employed. Water has a boiling point of 212° Fahr. at atmospheric pressure, a latent heat of vapour of 966'6 and a tension of vapour of 0'6 23, and having so high a boiling point it requires a vacuum of '089 lb. per square inch to boil at a tem- perature of 32° Fahr., and consequently a vacuum at the very least as high as this must be maintained to produce ice by the vacuum process. CHAPTER IV. The Abstraction of Heat by the Evaporation OF A Separate Refrigerating Agent of a MORE or less Volatile Nature, avhich Agent IS SUBSEQUENTLY RESTORED TO ITS ORIGINAL PHY- SICAL Condition by Mechanical Compression AND Cooling, or the Compression Process. So far the refrigeration has been effected by evaporation, the air gaining access under natural conditions, or by an artificial draught, or the evaporation has been accelerated by reducing the atmospheric pressure, the latter operation being next still further facilitated and rendered practically continuous by pro- viding for the absorption of the vapour given off or evolved by means of an absorbent, such as sulphuric acid. More volatile liquids, however, are employed as agents, such as, for instance, alcohol, sulphurous and carbonic acids, bisul- phide of carbon, gasoline, ether, methylic and sulphuric ether, carbon bisulphide, methyl chloride, ethylene, anhydrous am- monia, &c. In the year 1755, Dr. Cullen found that, by removing the atmospheric pressure, ether and other liquids which boil at low temperatures would evaporate at temperatures below freezing point, with sufficient rapidity to congeal water brought into contact with the exterior surfaces of the vessels or receptacles wherein they were contained. In a refrigerating and ice -making apparatus invented by Jacob Perkins about the year 1834, compression was first in- troduced, the volatile liquid used, according to Sir Frederick Bramwell, being one derived from the destructive distillation of caoutchouc. This invention of Perkins' is the origin from which has sprung all those machines operating upon the com- pression principle. Perkins' apparatus is shown in Fig. 4 in side elevation, partly 22 REFRIGERATING AND ICE-MAKING MACHINERY. in vertical section, and consists simply, as will be seen from the illustration, in a jacketed pan a, clothed externally with non-con- ducting material, and a pump b connected to the upper part of the jacket, and to the first or uppermost convolution of a coil or worm fitted in a tank or vessel c wherein cooling water can be freely circulated, and the last or lowermost convolution of which coil or worm is connected to the lower part of the said jacket. The water to be frozen is placed in the jacketed pan, the space ov clearance between the latter and the jacket being partially filled with the distillate from caoutchouc, or the ether, or other vola- tile liquid intended to form the refrigerating agent. The vapour given off or evolved from the volatile liquid contained in this space or clearance is drawn otf from the top by the pump b, and Fig. 4. is delivered compressed to the water-cooled worm or coil, which is shown by dotted lines in the tank c, wherein it is again liquefied and returned from the bottom of the latter to the lower part of the said space or clearance. The complete cycle of operations is thus continuous, and the only loss of the volatile liquid used as a refrigerating agent that is possible, is that which may take place through leakage. The system of absorbing heat and thus producing cold, partly by the expansion and vaporization or gasifying, and sub- sequent liquefaction, and partly by compression and cooling, is in accordance with the well-known law of physics, viz., that all gases during the process of passing from a liquid to a gaseous state are bound to absorb a certain amount of heat, and whilst returning from a gaseous to a liquid state to give up or throw off the same amount of heat. Whatever the refrigerating or heat-absorbing agent that may THE COMPRESSION PROCESS. 23 be used, the following cycle of operations is obligatory in all machines working upon this principle, viz. : — First, compression, that is the refrigerating or heat-absorbing agent in gaseous form, is subjected to a pressure sufficient to reduce it to a liquid form, the said pressure varying with the nature of the agent, and the temperature of the condensing water. During this compression, a degree of heat is developed in accordance with the amount of pressure to which the gas is subjected, or to the volume to which it has to be reduced rela- tively to that of the gas, in order to produce liquefaction. This heat is carried off by means of condensing or cooling water. Second, condensation, during which process the heat de- veloped during the above-described compression of the gas is carried away by forcing the latter through water-cooled pipes, the heat being transferred to the said cooling water. At this point the gas is ready to assume the liquid form, in doing which an additional amount of heat is given off to the said water. Third, expansion, during which the liquefied gas is admitted to series or coils of pipes, and being suddenly relieved of pres- sure, instantly flashes or expands into a gaseous form ; in doing which, according to the above-mentioned law of physics, it is forced to absorb or take up a quantity of heat which it renders latent, and which it draws from the surrounding objects, viz., firstly, of course, the pipes or coil wherein it is confined, and secondly, such substances as may be brought m contact with the latter, and which it is desired to cool, as air, water, brine, &c. The amount of heat thus abstracted or absorbed is equal to that previously given up to the cooling water in the condenser, the gas being then ready for compression, &c., and the cycle of operations can thus be repeated ad infinitum. These three operations being essential, all machines of this class, howev.er much they may differ in more or less important points of detail, must perforce consist of the following three series of parts, viz. : — First, a compression side, wherein the gas is compressed in some suitable and convenient manner. Second, a condensing side, wherein the gas circulates through water-cooled pipes or coils or their equivalent, gives off its heat, and liquefaction takes place. Third, an expansion side, consisting of pipes or coils, or 24 REFRiGERATiNG ANt) ICE-MAKING MACHINERY. other space, wherein the gas can re-expand and perform its work of coohng or refrigerating, by abstracting heat in the above-described manner from the surrounding objects. It will be seen that the heat only that has been acquired by the refrigerating agent is rejected, the latter being used over and over again, the only loss, therefore, is that sustained through accidental leakages. Such liquids only, however, are capable of being used as re- frigerating agents as possess vapours capable of being liquefied under pressure at ordinary temperatures. Hence, owing to the latter operation being an absolute essential, it is generally known as the compression process. The next attempt at improvement in these machines was made by Professor Twining, who obtained a patent for his inven- tion in this country in 1850, and in the United States in 1853. His apparatus comprises an exhaust or expansion vessel, a pump, and a condenser. The water to be frozen is placed in cham- bers or cells situated between thin metal pipes, plates, or par- titions, through which circulates the vapour evolved from a suitable volatile liquid, such as ether, sulphide of carbon, &c., which vapour i ; drawn off by an air pump, compressed, con- densed in a coil or worm, cooled by water, and is then returned to the reservoir in which it is once more vaporised, in a manner substantially similar to that of Perkins'. In fact, as already in- timated, all machines of this class are bound to operate upon the same principle as that of the latter inventor, and can only differ therefrom in details of construction of more or less im- portance. It is stated that a machine of Twining's, of a capacity designed to produce 2,000 lbs. of ice in twenty-four hours, was in operation in 1855 in Cleveland, Ohio; and that, although working under somewhat serious disadvantages, it did actually produce 1,600 lbs. of ice per twenty-four hours 'in a toler- ably satisfactory manner, and was in use off and on for about three years. Another machine, which comprises certain further improve- ments on Perkins' apparatus, was invented and patented by James Harrison in the year 1856. The novel feature claimed especially, in Harrison's compres- sion machine, is the evaporation of volatile liquids in vacuo, and the reduction to a liquid form in a separate vessel by pres- sure. The essential parts of his apparatus consist of three vessels connected by tubes, a vacuum being established through- TltE COMPRESSION PROCESS. 25 out the apparatus, and the air being expelled by the vapour of ether, ammonia, or other volatile liquid. The first vessel is charged with the volatile liquid ; the second vessel contains a pumping and compressing apparatus, by means of which the vapour is withdrawn from the first vessel and forced into a third ; and the third or last vessel is immersed in water or kept moist, so that the heat generated by the compression and Hquefaction of the vapour may be carried off. The resuUing liquid passes into the first vessel to be again evaporated under diminished pressure, and again withdrawn, compressed, liquefied, and returned, the process being capable of indefinite prolongation, until the apparatus be either injured or becomes worn out. The general arrangement of an improved Harrison machine constructed by Siebe Gorman & Co., is sho\vn in side elevation in Fig. 5, wherein a is the sieam-engine cylinder; b is the Fig. 5- pump or compression cylinder, which is kept cool by a suitable water-jacket; c is the refrigerator, which consists of a copper cylinder, fitted with sets of copper tubes arranged horizon- tally ; D is the ether condenser, which is composed of sets of copper tubes also arranged horizontally in a wooden tank or casing, and cooled by a circulation of water. Suitable connections are provided between the refrigerator c, pump B, and condenser d. The refrigerating agent employed in this apparatus is sulphuric ether, which is the result of the action of sulphuric acid upon vinous alcohol, and which has a specific gravity of 2b REFRIGERATING AND ICE-MAKING MACHINERY. 0720, a latent heat of vaporisation of 165, a specific gravity ot vapour of 2-24 as compared with air, and the boiHng point of which is 96° Fahr. at atmospheric tension. The liquid sulphuric ether is delivered from the condenser d to the refrigerator c, through a pipe fitted with a stop cock by means of which the amount admitted can be nicely adjusted to the capacity of the pump b. The weight of ether capable of being drawn off by the said pump b is dependent upon the pressure at which evaporation takes place, as it is perfectly obvious that the denser the said vapour, the greater the weight drawn off at each stroke of the pump. In order to ensure this apparatus working up to its fullest capacity the boiling point of the sulphuric ether must be so regulated as to impart the exact reduction of temperature desired, consequently the pressure at which evaporation is caused to take place depends upon the degree of temperature to which it is required to lower the brine. The amount of water required to be passed through the ether condenser d, for cooling purposes, naturally varies in dif- ferent climates, and in accordance with the season of the year; in this country it is stated to be about 150 gallons per hour for each ton of ice produced per twenty-four hours. The liquefac- tion of the vapour is said to take place with cooling water at the temperature usually obtainable here at a pressure of some 3 lbs. per square inch above that of the atmosphere ; in a hot climate, however, a very much higher pressure is required, rising some- times to as much as 12 lbs. above that of the atmosphere. The apparatus, when employed for making ice, is provided with an ice-making tank, usually fitted with copper.moulds ; or, when used for refrigerating purposes, it may be connected with a system of cooling pipes. The brine circulation is maintained by means of a suitable pump, and the brii.e, which is, as a rule, reduced to a temperature of about 10^ Fahr. during its passage tlirough the sets of tubes in the refrigerator c, is returned, after circulation, to the said refrigerator to be re- cooled. The sets of tubes in the refrigerator are so arranged that the brine to be cooled circulates through them succes- sively, being thus gradually reduced in temperature. When employed for cooling water or other liquids, the said liquid is usually passed at once through the refrigerator c in place of the brine. In Charles Tellier's apparatus, which was designed some years later, the refrigerating agent employed is methylic ether, THE COMPRESSION PROCESS. 27 which liquid has a latent heat of vaporisation of 473, and which enters into ebullition at tension of the atmosphere at a tem- perature of from 20° to 25° below zero Fahr., whereas sul- phuric ether, employed in the improved Harrison machine, as before mentioned, boils at 96° Fahr., a difference, of about 121°. Methylic ether is the result of the action of sulphuric acid upon ligneous alcohol, that is to say, alcohol distilled from wood. To obtain methylic ether, sulphuric acid is mixed with ligneous alcohol in equal proportion, and heated until the ether is evolved, carrying with it a number of bye pro- ducts, such as sulphurous acid, carbonic acid, and empyreu- matic vapours, which must be eliminated by passing the im- pure vapour through or over liquids, etc., by which they will become absorbed and retained. For instance, by passing the adulterated vapour over potash, the carbonic and sulphurous acids will be retained by the alkali, the aqueous vapour being at the same time carried away mechanically. In the distillation of methylic ether on a large scale, a great difficulty would be experienced, under ordinary conditions, in getting a liquid, having so low a boiling point as — 25° Fahr., to flow through the requisite pipes. To overcome this difficulty, Tellier designed the special apparatus illustrated in sectional elevation in 2 8 REFRIGERATING AND ICE-MAKING MACHINERY. Fig. 6, wherein the vapour, after purification, .is brought back to a liquid state by pressure, and is thus rendered manageable. In the drawing a, b, c are large cast or wrought-iron drums or receivers ; d is the purifier; e is a special pump which sucks oft the purified vapour and delivers it through the worm F in a liquid state into a set of receivers G, which latter are cap- able of withstanding a very high pressure, and from whence it can be drawn off, and will flow through the rest of the apparatus as easily as water. Tellier's apparatus for the production of cold is shown in elevation in Fig. 7, wherein a is the refrigerator; b is a re- ceiver or vessel in which the methyhc ether is evaporated ; c is the pump for drawing off the vapour - from the latter; and d is the con- denser, which is fitted with a suitable worm or coil. The vaporised me- thylic ether is either em- ployed to lower the tem- perature of a solution of brine, by passing it through a series of tubes situated in the relli- gerator and plunged in the latter ; or it is carried on and permitted to expand in a suitable system of pipes, and so act direct to reduce the tem- perature of air-tight chambers. When in operation it is found THE COAIPRESSION PROCESS. 29 that the pipes leading from the receiver b are so cold that they become coated with hoar frost; whilst, on the contrary, when giving up the absorbed heat during compression and liquefac- tion, the gas raises the tubes to a very high temperature, sometimes even approaching to a red heat. The liquefaction of the methylic ether in the worm or coil of the condenser _D gives rise to a certain amount of pressure, and to allow for this, and at the same time to permit a supply of the liquid to pass from the said condenser to the receiver b as required, a device called a distributor, the construction of which will be readily understood from the en- larged sectional view. Fig. 8, is employed, e is the aper- ture through which the liquid methylic ether is delivered to a small chamber or recess F. G is the outlet aperture, the upper portion of which is bifurcated as shown at g'^, g\ and which communicates with the refrigerator. h is. a valve having two recesses h\ h\ which correspond with the holes or apertures g\ g^, and which valve is mounted on a spindle i, which is capable of being rotated through the bevel or ^^S- §• mitre gearhig k, and shaft L, and works upon a suitable seating in the bottom of the said recess or chamber f. During the revolution of the valve h in the chamber f, which latter is always maintained full of lique- fied methylic ether, the recesses h become filled with the latter, and every time that the said recesses pass over the cor- responding holes or ways g\ the hquid contained therein falls by gravity into the latter and passes away to the refrigerator through the outlet g. About the same time as the preceding, an ether machine was patented by Delia Beffa and West, which comprised a multi- tubular refrigerator in which the ether was volatilised, a double- acting air or vacuum pump exhausting this vessel and pumping 30 REFRIGERATING AND ICE-MAKING MACHINERY. the ether vapour into a condenser;, and Ukewisea special forir, of the latter for condensing the said ether vapour. The following particulars regarding an ether machine are given* by Mr. Lightfoot as being the result of actual experiments made in this country, and serving to show what may be expected under ordinary conditions : — Production of ice per twenty-four hours ,, .. 15 tons. ,, ,, per hoiu- .. .. .. .. 1,400 lbs. Heat abstracted in ice-making, per hour . . 245,000 units** Indicated horse-power in steam cylinder, excluding that required for circulating the cooling water and for working cranes, etc. . . . . . . 83 I.H.P. Indicated horse-power in ether pump . . . . 46|- I.H.P. Thermal equivalent of work in ether pump, per hour, 1 19,26 1 units** Ratio of work in pump to work in ice-making . . i to 2*05 Temperature of water entering condenser . . . . 52^ Fain". Mr. Frederick Colyer,C.E.,M.I.C.E., statesf that he obtained the following results with a first-class apparatus when testing the working of some of the leading ether machines, viz. — " In an ether machine made by Messrs. Siebe Gorman & Co., capable of cooling 3,200 gallons of water from 60° down to 50° or ab- stracting 320,000 heat miits"'' per hour, the average experi- ments gave 4,250 gallons per hour cooled 10° Fahr. The temperature of the water at the inlet was 54° and that of the water used for condensing purposes was the same. The maximum cooling effected v/as 449,437 heat units^''^* abstracted per hour, being from 35 to 40 per cent, above the nominal power of the machine. The condensing water used per hour was 1,262 gallons, or about 3-ioths of a gallon for. every gallon of water cooled. The coal consumed was 3^ cwts. per hour; it was of indifferent quality, or the consumption would have been smaller. The steam cylinder was 21 in. diameter and 27 in. stroke; the air-pump 24 in. diameter and 27 in. stroke. The speed of the engine was 58 revolutions per minute, with 48 lbs. of steam cut off at one-third of the stroke. The indi- cated power of the engine was 53 horse-power, and of the air- pump 29*2 horse-power. The boiler was 7 ft. diameter and 24 ft. long, and gave an ample supply of steam." This, he stated, was the most efficient ether machine that had * "Proceedings, Institution of Mechanical Engineers," 1886, page 214. ** A thermal unit is that amount of heat required to raise the tem- perature of I lb. of water 1° by the Fahr. scale when at 32°. t " Proceedings, Institution of Mechanical Engineers," 1886, page 248. THE COMPRESSION PROCESS. 3 1 come under his notice at that date, and contained several improvements not usually found in others of the same class. According to the same authority the ether system is more expensive than the ammonia system (which latter will be next considered), especially in London where coal is expensive, and water has frequently to be obtained from the water companies. The latter item is undoubtedly in this case one of considerable moment, as water is required in larger quantities for condensing purposes in the ether system, and consequently the high tempera- ture which it sometimes attains in the street mains during the summer months becomes a matter of serious importance, as regards the economical working of the machines. Other objections to the use of ether as a refrigerating agent are, that, owing to its low vapour tension, a very large volume has to be circulated to perform a given refrigerating effect, thus abnormally increasing the dimensions of the apparatus ; rapid deterioration under repeated vaporisation and recondensa- tion ; -and finally that it is extremely inflammable and ex- plosive. On the other hand, however, it is possessed of the quaUty of working with a low pressure in the condenser, which renders its use advantageous in hot climates. Van der Weyde's (American) apparatus comprises exhaust and force pumps, a cooling coil and two refrigerators, the latter also acting as reservoirs for the condensed liquid. The most usual refrigerating agents employed are naphtha, gasoline, rhigoline, or chimogene."^ The water to be frozen is placed in moulds or vessels plunged in other vessels containing glycerine, and which latter are surrounded on the outside by cyrogene. The naphtha, gasoline, rhigoHr.e, or chimogene is evaporated by means of an air pump and forced through the refrigerator, the evaporation of the said cyrogene abstracting sufficient heat to form ice. In Raoul Pictet's machine sulphur dioxide or sulphurous acid (SO 2) is employed as a refrigerating agent. Sulphur dioxide is prepared by burning sulphur in dry air or oxygen gas, or by removing the elements of water, and an additional atom of oxygen from sulphuric acid by heating it together with copper clippings or mercury. The purification of the resultant gas is effected by washing, and it is collected either by displacement, or over mercury. It is completely colourless, has the over- ♦ Knight's " Practical Dictionary of Mechanics." 2,2 REFRIGERATING AND ICE-MA KING MACHINERY. powering odour of burning sulphur, neither supports combus- tion or respiration, is 2*247 times heavier than air, is easily condensed, is liquefiable by cooling down to 14° Fahr. under ordinary atmospheric pressure, and congeals into a transparent solid at temperatures below — 168° Fahr. This gas deviates considerably from Boyle's law of pressures, and occupies less space for equal increments of pressure than does air under like conditions, this variation becoming more marked as the temperature is reduced. Sulphurous acid is extremely soluble in water, one volume of the latter at a temperature of 50° Fahr. being capable of dissolving 51*38, and at 68°, 36*22 volumes of the former. It has a molecular weight of 65 and a density of 32. The latent heat of vaporisation of this liquid is 182, and it boils at a temperature of 14° Fahr. at the tension of the atmosphere. In Pictet's apparatus the refrigerator and ice-tanks are com- bined, the circulation of the brine being effected by means of a fan, and the space occupied is thus considerably reduced, the efficiency being also somewhat augmented. In 1885 Pictet applied for a British patent for an improved material for use in refrigerating apparatus wherein anhydrous sulphurous acid is employed, consisting of the admixture with the latter of carbonic anhydride. The sealing, however, was successfully opposed and consequently no patent was granted for this invention. The employment of sulphurous acid is highly objectionable, by reason of its becoming converted, by combining with the constituents of the atmosphere, into sulphuric acid and cor- roding the machine. In a patented machine of Windhausen's the refrigerating agent employed is what is indifferently known as carbon-dioxide (CO2), carbonic anhydride, or carbonic acid, which material is gaseous at ordinary temperatures, and under ordinary pressures, but which liquefies at a pressure of 540 ibs. Carbonic acid gas does not burn, neither supporting combustion nor respira- tion. Windhausen's apparatus is fitted with a pair of compressors placed in Hne with steam cylinders of the compound type, arranged side by side with a surface condenser between them- The gas condensers are situated in the base of the machine, and a separate refrigerator is provided in connection with each of them, constructed of coils of wrought-iron pipes mounted in a steel casing, wherein the brine is circulated. The duolicate THE COMPRESSION PROCESS. 3.3 portions of the machine are usually so arranged as to admit of either of them being worked separately, or both together, if desired. This is advantageous inasmuch as it renders the apparatus practically equal to two independent or separate machines, and affords the same immunity from a complete breakdown. The later machines comprise several patented improvements by J. & E. Hall, Ltd., which firm are also (we Fig. 9. are informed) the proprietors of the original Windhausen patent. Fig. 9 is a vertical central section, some of the parts being left in elevation, showing the Windhausen compressor for treating the gas in two stages. Figs. 10 and 11 are enlarged views, showing more clearly the details of construction of the inlet or suction valve, and of the outlet or discharge valve. As will be seen from the illustration the inner cylinder a is surrounded by an annular space communicating with the former through the valve d ; c is the inlet which communicates with 34 REFRIGERATING AND ICE-MAKING IMaCHIXERY. the cylinder a through a suitable valve,, and through which the gas to be compressed is drawn or sucked into the said cylinder ; b is the piston, and e is a valve through which the annular space or clearance round the cylinder a communicates with a pipe leading to the condenser. In operation the gas is primarily drawn into the cylinder a, through the inlet valve c, where it is compressed, and discharged through the valve d to the above-mentioned annular space, wherein it is finally compressed by the oil shown in the latter and the cylinder a, which communicate at their lower ends through suitable holes or apertures, and which oil forms a liquid piston. After this second and final compression the gas is discharged through the valve e to the condenser. Another machine adapted for the use of carbon dioxide as a refrigerating agent is found in that of Lowe. It comprises a gasometer or gas-holder, a pump, a condenser or cooler, a drier charged with chloride of calcium, a water-cooled condensing coil, and a refrigerator or ice-making t^ank- In operation the THE COMPRESSION PROCESS. 35 gas is admitted to the pump, liquefied under the action thereof, and the heat thus generated is absorbed or taken up in the cooler, after which it is allowed to expand into the refrigerator, where it acts in the usual manner, and is finally returned to the gas-holder. Refrigerating machines on the carbonic acid or carbonic anhydride system are also made by the Pulsometer Engineering Company, Limited, and others. Carbonic acid, carbon dioxide, or carbonic anhydride (CO2) is completely inodorous ; and the further advantage is also claimed for it, that, as it has no affinity for copper, it can be used with that metal with impunity. This is an important quality for marine installations, and consequently it has been used to a certain extent for that purpose. On the other hand, however, it is a deadly poison and fatal to animal existence, and has the further drawback that with water at a temperature of 70*^ Fahr. it requires a very high pressure to liquefy it, viz., one amounting to about 1,000 lbs. per square inch, whilst when the temperature of the said water exceeds 80° Fahr. it is' for this reason practically impossible to economically employ it as a refrigerating agent at alL Carbonic acid or carbon dioxide must not, however, be mistaken for the still more deadly gas known as carbon mon- oxide or carbonic oxide gas (CO), the inhalation of even a minute quantity of which will produce death. Carbonic acid or carbon dioxide (CO 2), which is the poisonous gas found at the bottom of old wells, &c., and forms the choke-damp of coal mines, is nevertheless sufficiently dangerous, and accord- ing to Sir Henry E. Roscoe, F.R.S., the presence of only cio per cent, (i part per 1,000) of this gas will render air unfit for continued respiration. The same authority gives the vapour tension of carbon dioxide or carbonic acid, at 35*5 atmospheres at a temperature of 0° Cent. (32° Fahr.), and at 73*5 atmo- spheres at a temperature of 30° Cent. (86° Fahr.). According to Mr.T.B.Lightfoot, M.I.C.E.,* the horse-power required in carbonic-acid machines, for producing a given quantity of ice with cooling water at 90 degs., is just about double that required for producing the same quantity with cooling water at 50 degs. He is also of opinion that the refrigerating effect falls off so fast as to render a carbonic-acid machine practically useless long before a temperature of 87 degs. is reached. * Engineering, 6th December, 1805. CHAPTER V. The Compression Process {continued). — Ammonia Machines. The refrigerating agent now most largely employed, and by far the most efficient one known at present, is anhydrous ammonia (NH3), which has a molecular weight of 17 and a density of 8-5. This liquid boils at 40° below zero Fahr. at atmospheric pressure; it has a latent heat of vaporisation of 900, and a vapour tension of 108 lbs. per square inch at a temperature of 60° Fahr. Gaseous ammonia can be liquefied at a pressure of 128 lbs. to the square inch, at a temperature of 70° Fahr., and at a pressure of 150 lbs. at a temperature of 77° Fahr., the pressure required to produce liquefaction rising very rapidly with the temperature. To liquefy by cold it requires to be reduced to a very low temperature, viz., — 85*5° Fahr. The latent heat of ammonia is very great, con- sequently its value as a refrigerating agent is proportionately large. The only alterations required in an ether machine to render it suitable for use with anhydrous ammonia as a refrigerating agent, are those made necessary by reason of the higher pressure of its vapour, and of the injurious action which it exercises upon copper, which causes the use of brass or gun metal in any of the parts with which either the liquid or the vapour comes in contact to be undesirable. The chief advantages derived from the use ot anhydrous ammonia as a refrigerating agent are that it possesses greater heat-absorbing power than any of the others named, excepting water ; that it liquefies at a comparatively low pressure ; and that it is neither so deadly in its effects upon animal life as carbonic anhydride or carbonic acid gas (CO2), nor as explosive or inflammable as ether, and consequently its use is claimed to be practically free from danger. THE COMPRESSION PROCESS 37 Ammonia is, however, far from being perfectly innocuous and safe, and due precautions should be taken to avoid accidents where it is in use. It is a colourless irrespirable gas, having an extremely pungent, peculiar, and easily recognisable odour, and it is also slightly combustible when mixed with a sufficient pro- portion of air, burning feebly with a flame of a greenish-yellow hue, and when mixed with about twice its volume of air being capable of exploding with considerable violence. From this it will be clear that it is absolutely essential that no part of an ammonia apparatus should have a naked light inserted into it, until it has been open and exposed to the air for a sufficient time to render the presence of such light harmless. The tendency of ammonia gas, owing to its being only half the weight of air, is to rise when set free, so that there is the less likelihood of any person who might chance to be near when an ammonia pipe happens to burst, or a bad leak to take place, becoming overpowered by the gas. Another objectionable feature of ammonia, which has been already alluded to, is its very strong action on copper and its alloys, by reason of which no such material can be employed for any part of an ammonia machine. Common ammonia of commerce is a solution of ammonia gas in water, and its usual strength is 26° Beaume.^'" Anhy- drous ammonia is pure dry ammonia gas compressed to a Hquid, and it is manufactured by the distillation of the ordinary 26° ammonia of commerce in a suitable apparatus. This apparatus, which should be of sufficient strength to stand a pressure of 65 lbs. on the square inch, comprises a still, a condenser, three separators, and a drier or dehydrator. The still is heated, by a suitable steam coil, to a temperature of about 212° Fahr., when the ammoniacal gas, together with a certain amount of water, passes off into the first separator, which latter is usually situated on the top of, and forms an up- ward extension of, the still. In this first separator the greater portion of the watery particles carried over are eliminated by a series of perforated plates, through which perforations the gas has to pass, and are returned to the still through a dip pipe From this first separator the partially dried gas passes through a water-cooled worm in the condenser, and then successively through the two other separators to the drier or the dehydrator, where it is passed through a set of similiarly perforated plates * See Table of Comparison of various hydrometer scales, Page 244. 38 REFRIGERATING AND ICE-MAKING MACHINERY. to those in the first separator, but having small sized lumps of freshly burnt lime placed upon them, by which any moisture that may still remain in the gas is removed, and the completely anhy- drous product can then be passed into the ammonia pump or compressor. It is found advisable to work the still at a pressure of about 30 lbs. to the square inch, so as to admit of its being raised to a slightly higher temperature than the boiling point of water at atmospheric pressure, without causing the water to boil, the result of this being that the whole, or practically the whole, of the ammonia will be set free, whilst at the same time the least possible amount of the water will be vaporised and pass over with the said ammonia gas. To ascertain whether or not all the ammonia has been elimi- nated, two methods of testing the charge in the still are usually practised. The first is to draw off a small quantity of the charge, and if this fails to turn litmus paper, then the charge is exhausted, and all the ammonia has been driven off. The second is to allow a small amount of the gas leaving the still to escape through a small cock or valve specially provided for the purpose, when if this gas be tested with turmeric paper, and if this latter remains unchanged in colour (yellow), the charge is completely spent ; if, however^ the said paper on the contrary turns of a brown hue, there is still some ammonia left. After the distillation is finished the water remaining in the still should be run out, and as soon as the temperature of the latter is sufficiently lowered it can be again charged. The water accumulating in the second and third separators, being saturated with ammonia gas, may be returned into the still when recharging the latter. The amount of ammonia water, however, that becomes deposited in the said separators will be very small if the pressure in the still is maintained at about 30 lbs., as above-mentioned. The hme in the drier or dehydrator must be removed when- ever it is found to have become in any degree slacked. Commercial ammonia of 26° Beaume contains 38*5 per cent, of anhydrous ammonia by volume, it is therefore easy to calculate from this the quantity that it would be necessary to distil in order to produce any given amount of anhydrous ammonia. Ammonia gas or vapour is, owing to its searching nature, very troublesome to deal with, even at a low pressure, consequently this difficulty is greatly increased by the comparatively high pres- THE COMPRESSION PROCESS. 39 sure or tenuity that is obtained in a compression machine, and which rises in the condenser to as much as 180 lbs. per square inch. Leakage of the ammonia gas at the pump glands and other parts of the apparatus forms, therefore, the main objection to the use of ammonia as a refrigerating agent, and the means employed to prevent this leakage one of the chief points of difference between ammonia and ether machines. Another difficulty to overcome is the liability to an imperfect discharge of the gas from the compressor-pump, and the expansion and consequent back pressure of that remaining therein. The most important part of an ammonia machine working on the compression principle, and indeed of all apparatus where- in a volatile liquid is compressed, is the gas compressor. In ammonia machines both single and double-acting compressors are employed. A single-acting compressor has the advantage when working with a gas of the tenuity of ammonia, owing to its only carrying the lesser pressure of the suction side over the stuffing box, of preventing the said stuffing box from being subjected to the high pressure of the condenser, which is unavoidably done at the termination of each stroke in a double- acting compressor, and on this account the chance of leakage is, of course, greatly reduced. On the other hand, however, it is obvious that a double-acting compressor must be more advantageous from an economical point of view, inasmuch as it deals with twice the amount of gas at each revolution of the crank-shaft, that a single-acting compressor of the same diameter and stroke is capable of operating upon. Moreover, the same amount of friction is engendered in each case, although with a double-acting compressor double the duty is being performed, and the friction of th,v*', moving parts — such as the cross-head, piston, piston-rod, and connecting-rod — causes no inconsiderable loss, for to overcome friction, power has to be expended, and waste of power means Joss of fuel, i.e., money. The amount of saving effected in a machine having two gas compressors may be taken to be one-eighth of the whole amount of power required for compressing the gas. A further economy is that a double- acting compressor is capable of performing the work of a pair of single-acting ones of the same size, and consequently there is a saving in the first cost of the apparatus and in space occupied. The construction of a gas compressor for operating with ammionia does not, as already mentioned, vary in any very material point from that of one intended to work with ether, 40 REFRIGERATING AND ICE-MAKING MACHINERY. and, however much they may differ from one another in minor points of detail, they all work upon the following broad prin- ciples, viz. : — The gas compressor, which is operated by a steam-engine or other suitable motor, draws the gas or vapour from the eva- porating coils or tubes of the refrigerator after it has performed its duty of cooling, compresses it on the return stroke of the piston, and forces it into a system or series of pipes or coils in the condenser, in which coils, under the cooling action of water, it resumes its liquid form. From the condenser it is again passed in the liquid state, through a minute opening of the ex- pansion or regulating cock, into the evaporating coils or tubes of the refrigerator, wherein it again expands into gas or vapour, owing to the diminished pressure there prevailing, by reason of the sucking action of the gas compressor. The pressure in the pipes or coils in the refrigerator is usually maintained at from 15 lbs. to 30 lbs., whilst that in the condenser as above- mentioned; may rise as high as 180 lbs., the former depending of course on the amount of opening given to the expansion cock. The liquid ammonia passing suddenly from the above high pressure of the condenser to the comparatively low pressure in the refrigerator, instantly flashes into gaseous form, and whilst doing so, in conformity with the well-known natural law, is forced to absorb a quantity of heat which it renders latent; this it does from' the surrounding objects^ which in the present instance are either the pipes or coil in the refrigerator, and the brine circulating round the latter, or when used for cooling on the direct system, the sets of refrigerating pipes into which it is passed and the surrounding air. In order to avoid any chance of accidents occurring through the machine being started with all the valves closed, a suit- able relief or safety valve and bye-pass should invariably be provided. Expressed generally, then, the cycle of operations in machines on the ammonia compression system is the same as that of those described in the preceding chapter, viz., compression, condensation, and expansion ; and the said machines, no matter how they may differ in more or less important points of, constructional detail, must all likewise consist of three different parts, viz., a compression side, a condensing side, and an ex- pansion side. The said operations are rendered continuous by suitably connecting all these sides or parts together so that the gas passes through them in the above order. Fie. 12. 42 REFRIGERATING AND ICE-MAKING MACHINERY. Fig. 12 is a vertical central section illustrating the De La Vergne single-acting compressor, constructed by L. Sterne & Co., Limited. The chaiacteristic feature of this machine consists in the patented system for preventing the occurrence of any leakage of gas taking place past the stuffing box, piston, and valves, and extracting the heat from the said gas during compression, by the simple device of injecting into the said compressor, at each stroke, a certain quantity of oil or other suitable lubricating fluid. By means of this sealing, lubricating and cooling oil, not only are the stuffing-box, piston, and valves effectually sealed, and the heat developed during compression taken up, but all clearances are entirely filled up. This latter is a matter of the utmost importance, as it ensures a complete discharge of the gas from the pump cylinder, and were this not effected, and an imperfect discharge thereof only to take place, by reason of a portion of the said gas remaining at the termina- tion of each stroke in the clearance, however small, that must of necessity be ordinarily left between the piston or plunger, and the cylinder-head, the gas thus left over would re-expand on the reverse stroke of the said piston or plunger, and the pressure thus set up against the incoming charge of gas cause a very considerable loss of power and efficiency. This method of sealing the stuffing-box and piston enables the leakage and consequent introduction of air into the pump, or drawing out or wasting of a volume of the refrigerating gas at each alternate stroke of the piston, to be effectually pre- vented without necessitating the packing of the said piston and gland so tightly as to bind and set up an excessive amount of friction, the power required to overcome which has been some- times found to exceed that necessary to perform the entire work of compression. Moreover, when working constantly against a pressure of from 125 to 180 lbs., it is obvious that the slightest wear would cause a considerable leakage of gas to take place past the piston into the adjoining chamber, and like difficulties would also be encountered with the valves, allowing the gas to regain access to the pump cylinder by leak- ing past the discharge valves, or to be re-admitted to the suc- tion side past the corresponding valves. The losses occasioned in this manner through abnormal friction, and the reduction in efficiency and loss of valuable material through leakages con- stitute in some machines a very large item, and are the chief cause of failure to give satisfactory results. It is claimed by the inventor that the oil injected into the THE COMPRESSION PROCESS. 43 compressor cylinder for the above-mentioned sealing purposes, not only effectually overcomes the above difficulties, but also Fig. 13. acts in a more efficient manner to absorb or take up the heat generated during compression by the mechanical energy exerted 44 REFRIGERATING AND ICE-MAKING MACHINERYo by the compressor piston or plunger upon the gas, than does a water-jacket to the cyHnder and hollow water-cooled piston and rod, the useful effect of which latter is to a great extent prevented by the thickness of metal required in a pump destine/i to work at a high pressure. In order to ensure the highest efficiency in a compressor, it is essential that the heat generated by tlie act of compressing be eliminated as far as practicable, as otherwise THE COMPRESSION PROCESS. 45 the said heat, by expanding the gas itself during compression, increases its vokime, and consequently necessitates an opening of the discharge valve prior to the time that would be required were the gas cooled during compression. It is obvious that all the energy expended in effecting such premature dis- charge of the increased volume of gas is so much loss. The oil used is of a special quaHty, which is unaffected by the chemical action of the ammonia, it being absolutely essential 46 REFRIGERATING AND ICE-MAKING ^lACHINERY. tliat it be of a nature that will not saponify, and that is capable of withstanding both extremes of heat and cold. Fig. 13 is a vertical central section, showing a double-acting compressor on the De La Vergne system, fitted with Louis Block's patent arrangement of valves, the main object of which is to secure the discharge of the oil at the lower end of the cylinder taking place immediately after all the gas is gone and not before, as in the latter case re-expansion v/ill take place, resulting inloss of efficiency of the pump. To effect this, two valves are provided in the lower end of the compres- sor cylinder, one above the other. Either or both of these valves may open on the down stroke of the piston, until the latter covers the upper one, when only the lower one is left open to the condenser. During the remainder of the stroke of the piston, after the lower valve is also closed, the other or upper one opens communication with an annular chamber formed in the said piston. In the bottom of this annular chamber are provided, moreover, valves which open as soon as all the other outlets from the underside of the piston are closed, to ensure which they are loaded with springs, so arranged as to require somewhat more pressure to open them than the discharge valves on the side of the cylinder. The gas, and afterwards the oil, then all pass out through the piston, no trace of the former being present at the completion of the down stroke. In this mamierthe oil system of sealing can be advan- tageously retained, and the pump wuU w^ork as well at the lower side as the upper. Fig. 14 illustrates a complete De La Vergne refrigerating machine of a capacity of 220 tons. Fig. 15 shows a marine type of the De La Vergne machine. It is a vertical single-acting compressor, actuated by a high pressure horizontal steam-engine, fitted with a special governor, which admits of the steam supply being determined for wide ranges of speeds when required, say for any speed between 30 and 300 revolutions per minute, without interfering with the running, or stopping the machine. The construction of the compressor cylinder is identical with that illustrated in the enlarged sectional view. Fig. 12. A complete installation of a refrigerating plant on the De La Vergne ammonia compressor system is shown in side elevation in Fig. 16, from which view the circulation of the ammonia and sealing oil can be easily traced, viz : — 48 REFRIGERATING AND ICE- MAKING MACHINERY. Firstly. Following the path taken by the ammonia, in order to produce the frigorific effect, a is the compressor cylinder, which in this instance is of the double-acting type, and similar in construction to that shown drawn to a larger scale in Fig. 13 ; and R is the steam-engine cylinder, which is likewise arranged horizontally, b is a pipe through which the gas is drawn or sucked from the evaporating coils into the compressing cylinder a. The said gas is then discharged by the action of the compressor a through the pipe c into the pressure tank d, where the sealing oil or liquid, the course of which will be next followed, falls to the bottom; the upper half or portion of the said pressure tank being fitted with suitable cast-iron baffle or check plates serving to more completely retain the said oil and ensures its deposition. From the pressure tank d the gas, which still retains the heat due to compression, passes through the pipe e into the bottom or lower pipe of the condenser f, wherein, by the cooling action of cold water running over the pipes, the heated gas is first cooled and then liquefied. The ammonia, in this liquid condi- tion, is then led by the small liquid pipes g, through the liquid header h, into the storage tank i, from whence it flows through the pipe j into the lower part of the separating tank k, which latter must be constantly maintained at the very least three- quarters full. L is a pipe of small bore, through which the liquid ammonia is forced, by reason of the pressure to which it is now subjected, to the expansion cock or valve, through which it is injected into the evaporating or expansion coil N which is situated in the room or chamber to be refrigerated or cooled. The ammonia gas resulting from the expansion and evapora- tion of the liquid ammonia in the evaporating or expansion coil N, having absorbed or taken up the heat from the atmos- phere surrounding them, passes away through the pipes o and B, back again into the compressor cylinder, and the cycle of operations of compressing, &c., are again performed as above. Secondly. Following the course of the oil employed for seal- ing, lubricating, and cooling purposes, which, as previously mentioned, is heated with th e gas during compression, and is passed into the tank d, to the bottom of which it falls. From the bottom of the tank d, the said heated oil is con- ducted through a pipe a to the lowermost pipe of the oil- cooler b, which is practically similar in construction, but on a smaller scale, to the ammonia condenser, and is likewise THE COMPRESSION PROCESS. 49 cooled by sprayed or atomised cold water. After being suffi- ciently reduced in temperature in the oil-cooler b, the oil flows through the pipe c, strainer d, and pipe e, into the oil pump /, \vhich latter is so constructed that it delivers the cooled oil into the compressor, distributing it to either side of the piston or plunger during its compression stroke, that is to say, in such a manner that no oil is furnished during the suction stroke of the said piston, but only during the time of compressing, thereby cooling the gas during its period of heat- ing. The heated oil, after leaving the compressor, then again returns, together with the hot compressed gas, to the pressure tank D, and follows the same round through the oil-cooler b, strainer d and oil pump/, l^ack to the compression cylinder. It will be obvious that the oil, as well as the ammonia, is used over and over again, no loss or waste of either taking place except that which may occur through leakage. Any small quantities of oil, however, that may be carried over with the current of the gas from the pressure tank d into the condenser f, pass along with the liquid ammonia into the sepa- rating tank K, where, by reason of its greater weight, the said oil falls to, and collects at, the bottom of the said tank. As soon as a sufficient quantity of oil has become thus deposited, it is drawn off and passed through the oil-cooler back into the oil- pump. The oil reservoir or tank is also connected to the oil pump F. When the apparatus is employed for the manufacture of ice, the evaporating coils n are placed in a tank containing brine, sufficient space or clearance being left between them to admit of the insertion of ice-cans or moulds containing the water to be frozen. In this instance the steam used for driving the motor, after doing its duty in the steam-engine cylinder r, is led through the exhaust pipe s into a steam filter and con- denser, where it is purified and condensed. The purified con- densation water then passes from the said condenser into a water regulator tank, and from the latter through a water-cooled coil of substantially similar construction to that of the ammonia condenser f and oil-cooler b, and finally is delivered into the ice cans or cases, which are usually constructed of galvanised iron, through suitable india-rubber hose, fitted with stop-cocks or valves. When the water in the ice-cans or cases is frozen, they are lifted out and transported by means of the overhead travelling crane to the dip-tank or a sprinkler, where the blocks of ice are 5 50 REFRIGERATING AND ICE- MAKING MACHINERY. thawed or melted out, after which the empty cans are refilled with water through the hose, and the process of making other blocks of ice is commenced. The various parts are clearly indicated upon Fig. i6, and the paths taken by the ammonia, the sealing, lubricating, and cooling oil, and the steam are shown by the arrows. The advantages derived from the use of the sealing, cooling, and lubricating liquid in the compressor cylinder will become very apparent on a comparison of the diagram shown in Fig. 17, which was taken from a gas compressor worked without em- ploying the said liquid, with that shown in Fig. 18, which was taken from a similar compressor, but with the charge of liquid. The diagram shown in Fig. 17 was taken from a 14 in. X 28 in. single-acting gas compressor, working with a direct pressure of 157 lbs., and a back pressure of 20 lbs., and at a speed of thirty-six revolutions per minute, no sealing, cooling, and lubricating liquid being used, a indicates the adiabatic curve, and b the isothermic curve. The adiabatic curve is, as is well known, that curve which would be produced were the air or gas to be instantaneously compressed, that is to say, without transmission of heat, and ihe isothermal curve is that which would result if it were possi- ble to compress the same without raising its temperature at all. In actual working the curves obtained fall between the adia' batic curve and the isothermal curve. THE COMPRESSION PROCESS. 51 It will be seen by an inspection of this diagram that the compression curve, which by right should approach the adia- batic curve a, on the contrary falls into close proximity to the isoihermic curve b, and indicates the existence of a leakage past the piston of 15 '2 per cent, of the gas being compressed, and as is shown by the curved Hne, which is produced by the re-expansion of the gas filling the clearance between the piston and compressor head or cover, a further loss from the latter source of 7*4 per cent., that is a total loss of 22*6 per cent., due to not employing the liquid. The horse-power shown on this indicator card is 44. The diagram shown in Fig. 18 was taken from a similar corn- Fig. 18. pressor running at the same speed, and working at 150 lbs. direct pressure, and with a back pressure of 27 lbs. The actual power indicated by this card is 48. The horse-power measured to the adiabatic curve a equals 53-6. The horse- power saved by employing the sealing, lubricating, and cooHng liquid is 5*6 for each compressor, or in a machine having two compressors a total saving of ii'2 horse-power. The efficiency of the compressor is gS'6 per cent, of its theoretical value, a result attained by the use of the liquid. The efficiency of the compressor, as indicated by the card shown in Fig. 17, is only 77 per cent, of that indicated by the card shown in Fig. 18, the loss being the result of the non-use of the said liquid. Fig. 19 shows a diagram taken from a 12 in. X 24 in. double- 52 REFRIGERATING AND ICE-MAKlNG ^^IACHINErY. acting gas compressor, running at a speed of thirty-four revolu- tions per minute, and fitted with Louis Block's patent im- provements, which latter have been already described on page 47. _ _ The steam cylinder actuating the above-mentioned 14 in. X 28 in. gas compressor, whilst the diagrams shown in Figs. 17 and 18 were being taken, was 18 in. X 42 in., and was working under a steam pressure of 68 lbs. per square inch, the speed being, of course, the same as that of the gas compressors, viz., 36 revolutions per minute. Indicator diagrams taken from the said steam cylinder showed on the card an initial pressure of 65 lbs., and the ^/vsjt^'.. rrc^lcA /a Fig. ig. mean effective pressure of the diagrams equalled 32-4 lbs. The horse-power developed was 6^, and the expansion line approached so close to the theoretical curve, as to show that the cut-off valve worked well, thus effecting a great economy in steam consumption. Machines on the compression system have been devised by a number of others, certain specific improvements, in most instances patented, being claimed to give to each of them some particular advantage. Amongst those having some special or distinctive features, mention may be made of those of Frick, Linde, Fixary, Neubecker, the Pulsometer Company, Kilbourn, Lightfoot, Pictet, Puplett and Rigg, and Haslam. The characteristic feature in the Frick machine is the means adopted for permitting the compressor to be safely worked without clearance, and thereby ensuring the complete, or THE COMPRESSION PROCESS. 53 practically complete, discharge of the gas therefrom. Two forms of compressors, constructed on this principle, are illus- trated in Figs. 20 and 2j, 54 REFRIGERATING AND ICE-MAKING MACHINERY. Referring to the drawings, a is the compressor pump piston, in which is placed the suction valve B, which is of ample area, and is balanced by a spring ; the said piston working metal to metal against the top cylinder head without clearance, c is the inlet for the ammonia gas, and d is the outlet valve through which the compressed gas is discharged from the pump bariiel or cylinder through the aperture in the apex of the dome e. F is a jacket surrounding the pump cylinder, and into the clearance or space thus provided, a constant stream of cold water is kept circulating, so as to take up as much of the specific heat of compression, and of the latent heat, through the wall of the cylinder as possible, and thus obviate super- Fig. 21. heating thereof, g is a relief valve situated in the cylinder head, and normally retained upon its seating by a powerful spring, G^ The ordinary discharge or outlet valve d, which is situated centrally in the large relief valve G, is a^so governed by a spring h. i is the piston rod stuffing box. k is an oil reservoir and hand pump for lubricating the piston rod, and through the small plug and valve l the pump cylinder when required, which is usually only when starting a new machine, or one that has been standing for a considerable time ; the latter also serves for the attachment of an indicator, to enable indicator diagrams to be taken from the pump. It will be seen that the compressors in question are of the single-acting type, the pistons are long, and are each provided with five carefully fitted rings, and the arrangement of the stuffing boxes and glands (shown in section in Fig. 20) is such as to render the escape of gas round the piston rods practically impossible under proper working conditions. THE COMPRESSION PROCESS. 55 The two compressors shown in Figs. 20 and 2 1 are constructed upon a substantially similar principle ; that shown in Fig. 21, however, has certain improvements in detail, chiefly relating to the patent safety, head, and discharge valve. In both arrangements the discharge valve, relief valve, together with the guides, speeder, and false seat, are entirely self-contained and independent of the pump cylinder, rendering it possible to expeditiously replace the whole mechanism by a new one, or to speedily execute any necessary repairs. In the latter arrangement, however (Fig. 21), the valve mechanism can be more easily got at, it being only necessary for that purpose to remove the light pump head. For convenience of illustration the cylinders are shown in the drawing in horizontal positions, but in actual practice the Frick compressors are usually placed vertically. The operation is as follows : — The suction valve b being, as before mentioned, of very ample area and balanced by a spring, affords no resistance to the passage of the gas upon the return or backward stroke of the piston, but allows of its flowing freely and rapidly into the pump cylinder, through the gas inlet c, under the action of the back pressure, to the vacant space above the piston. The rapid closing of the suction valve b at the instant of the piston beginning its forward or up-stroke is en- sured by a cushion spring, and the gas is gradually compressed until it equals the condensing pressure acting upon the discharge valve in the rehef valve located in the cylinder head, which then opens to admit of its escape to the condenser. There being no clearance between the piston a, when at the termina- tion of the up or forward stroke, and the cylinder head, no gas remains in the cylinder to re-expand on the return or backward stroke of the said piston, and destroy the vacuum. It will be seen that it is rendered possible to do this with perfect safety, as in the event of any foreign body or obstruc- tion getting accidentally between the piston a and the cylinder head, the valve or movable portion g of the latter, which is of the full dimensions of the pump bore, will give way and allow the compressed gas to pass into the dome e, and thence to the condenser, the said movable portion or relief valve G being returned to its seat, under the action of the spring g^ and the back pressure. Under normal conditions, however, the relief valve g does not work, the discharge, as already men- tioned, being effected through the smaller discharge or outlet valve D, which is usually of steel, and is fitted upon a seat in 56 REFRIGERATING AND ICE-MAKING MACHINERY. the centre of the movable portion of the head or relief valve G. Were no provision, such as the above-described relief valve or safety head G, provided, and any obstruction to become accidentally interposed between the piston and the cylinder end, not only would the latter be knocked out, and serious damage to the mechanism ensue, but the full charge of ammonia gas, which in a large machine is worth a considerable sum, would be lost. The ammonia compression machines designed by Carl Linde, and first patented by him in the year 1870, have been in exten- sive use for some years, more especially in Germany, and are said to give very favourable results ; they are made in several different patterns. In the land type of Linde machine, double ammonia com- pressors, arranged in line horizontally and driven from a crank upon a crank shaft placed centrally between the two compres- sors, and at right angles thereto, are employed. The necessary motion is imparted to the said crank shaft by means of a tandem compound jet-condensing engine. In the marine type a single compound ammonia compressor is employed, which is also driven by means of a tandem com- pound engine. The ammonia condenser is situated below the compressor, and is fitted with sets of endless coils or worms. By the use of a compound compressor, that is to say, one wherein the compression of the ammonia gas is effected in two stages, the loss from re-expansion of gas left in the clearances is completely got rid of, as such loss is experienced in the low pressure compressor cylinder only, none taking place in the high pressure compressor cyhnder. The method employed by Linde to prevent leakage of gas past the piston rod stuffing box and gland, is to provide a chamber or recess in the said stuffing box, glycerine or some other suitable lubricant being constantly forced into this cham- ber or recess at a somewhat higher pressure than that existing in the compressor cylinder, the result of which is that the ten- dency is rather for the lubricant to leak or escape inwardly, than for the ammonia to leak outwardly. A suitable separator is provided for the elimination of any lubricant that finds its way into the pump or compressor cylinder, and passes out with the ammonia. Another important feature in the Linde machine, is the method of cooling the vapour in the compression cylinder, by THE COMPRESSION PROCESS. 57 the introduction into the latter of a small portion of liquid am- monia with the said gas or vapour, at the commencement of each stroke, whereby it is reduced to a refrigerating temperature. According to Mr. Lightfoot, the following are the results that were obtained from tests made, in an exhaustive and impartial manner, by a committee of Bavarian engineers, with an ammonia compression machine constructed on the Linde system, and erected in a brewery in Germany : — " Nominal capacity of macliine, ice per 24 hours . . 24 tons Actual production of ice, per 24 hours . . . 39-2 tons ,, ,, ,, per hour .... 3,659 lbs. Heat abstracted in ice-making, per hour . . . 731,800 units. f Indicated horse-power in steam cyUnder, excluding that required for circulating the cooling water, and for working cranes, &c 53 I.H.P. Indicated horse-power in ammonia pump . . .38 I.H.P. Thermal equivalent of work in ammonia pump, per hour 97,460 units f Ratio of work in pump to work in ice-making . . i to 7-5 Total feed-water used in boiler, per 24 hours . . 26,754 lbs. Ratio of coal consumed to ice made, taking an evapora- tion of 8 lbs. of water per lb. of coal . . . i to 26-3 The pumps were driven by a Sulzer engine, developing one indicated horse-power with 21*8 lbs. of steam per hour, includ- ing the amount condensed in the steam pipes. The Fixary compressor is shown in vertical central section, some of the parts being left in elevation, in Fig. 22. It consists of two vertical, single-acting cylinders a, b, having an equalising chamber c, situated between them, at the upper extremity of which is provided a small valve governing an aperture leading to the suction side of the compressor. In the upper extremity of each of the cylinders a, b, are provided two valves, that on the right-hand side opening inwardly and being the suction or inlet valve, and that on the left-hand side opening outwardly and being the outlet or delivery valve. The space below the pistons is filled with oil which lubricates the said pistons, whilst at the same time preventing the gas from escaping past them to any great extent. Any gas that does find its way beneath the pistons passes into the equalising chamber c, where any accu- mulation of it is drawn off by the compressor, through the small valve in the upper extremity thereof, and one or other of the * "Proceedings, Institution of Mechanical Engineers," 1886, page 218. t A thermal unit is the amount of heat necessary to raise the temperature of I lb. of water 1° by the Fahr. scale when at 32°. Mech. eq. 772 ft. pounds. 58 REFRIGERATING AND ICE-MAKING MACHINERY. suction or inlet valves, and again returns to the system through the outlet or delivery valves. The oil that may be carried through the valve in the equalising chamber, serves the purpose of sealing the valves and filling up the clearance spaces. The characteristic feature of the Neubecker system is the special device for preventing leakage taking place round the piston rod. To effect this, the stuffing or gland box, through which the piston-rod passes, is so enlarged as to form an annu- lar recess or chamber surrounding the rod, which chamber is partly filled with oil, and maintained at a corresponding pressure to that prevailing in the surrounding atmosphere, by means of a compensating chamber, which latter is connected at its upper extremity to a small auxiliary pump through a pipe, the inlet to which is governed by a valve connected to, and controlled by, a metallic diaphragm, the upper side of which diaphragm is exposed to the pressure of the atmosphere. The operation of this compensating chamber is as follows : — The gas which may escape into the stufiing-box chamber, passes into the said compensating chamber, and as soon as sufficient has thus accumulated to raise the pressure therein above that of the atmosphere, it acts upon the flexible diaphragm to expand it outwardly, and thereby open the valve communicating with the above-mentioned auxiliary pump, by which the said gas is drawn oft" or removed and delivered into the refrigerator. The pressure in the separating chamber then again falls below that of the atmosphere, and the diaphragm being forced inwardly by the atmospheric pressure, the outlet valve closes. The lower portion of the compensating chamber forms a well, wherein any oil that leaks past the piston-rod gland of the compressor, as also that coming from the separator, accumulates, and is heated by a steam coil or worm, so as to drive off" any gas that has been absorbed by the said oil, after which the latter is drawn off from the bottom of the said com- pensating chamber to be cooled and filtered for further use. In Figs. 23, 24, and 25 are illustrated various patterns of compressors constructed by the Pulsometer Engineering Com- pany, Limited, on their improved system. Fig. 23 shows a small complete ice-making plant on the ammonia compression system, intended to turn out i ton of clear block ice per, twenty-four hours ; installations on the same principle are, however, made by the company wath a capacity for an output up to 25 tons of ice or more per day of twenty - four hours. THE COMPRESSION PROCESS. 59 In a type of apparatus particularly suited for export, every- thing, including the steam-engine, compressor, gas condenser, refrigerator, and ice tank, is mounted on one continuous bed, all the ammonia connections are ready made, and the whole can be readily put in one case and sent abroad, all that is neces- sary on its arrival being to charge the machine with gas and the ice tank v^^ith brine. Fie. 2: In the case of a small machine, such as that shown in Fig. 23, either a vertical high-pressure engine, as shown in the drawing, or an horizontal one, or any other suitable motor, is employed ; for larger sizes, however, these makers prefer to use cross compound condensing engines of the horizontal type, and of extra size to provide an ample margin of power in hot weather, and to give the best results as to saving of steam consumption from an early cut-off, and each engine driving a 60 REFRIGERATING AND ICE-MAKING MACHINERY. compressor tandem. The engine condenser is generally made of the surface condensing type, and, together with the water Fig. 23. circulating pump, placed between the engines and driven from the low-pressure crosshead. This arrangement has been found in practice to be, with long strokes of, say, at least 30 inches, THE COMPRESSION PROCESS. 61 most reliable, and it admits, moreover, in the event of an emergency, of running at a high speed. In cases where the very highest economy is desirable, triple or quadruple expan- sion engines are desirable. Fig. 25 illustrates one of a pair of pumps employed in a brewery and having a cooling capacity of one hundred barrels per hour. As will be seen from the drawing (Fig. 25), the ammonia Fig. 24. pump is of the double-acting type, and is arranged horizontally. It is intended to be driven from any convenient source of power already extant in the brewery. To obviate leakage and loss of ammonia gas, the stuffing box is fitted with a special oil-lubricating arrangement, by means of which a gas-tight joint is secured without any necessity for screwing up the gland so as to grip too tightly. The valves work without any springs or buffers, and in the larger sizes are so arranged that they can 62 REFRIGERATING AND ICE-^IAKING MACHINERY. be adjusted from the exterior; they are also of ample area, thereby reducing the pressure on the pump, and preventmg the latter and the engine from being overworked. The condenser is fitted with sets or series of lap-welded tubes, which are subjected to hi.^h tests both by hydraulic and air pressure, and are secured in a patented arrangement of THE COMPRESSION PROCESS. 63 return heads or ends of forged steel. The inlet and outlet valves are also of forged steel. The refrigerator consists of a welded steel shell, having ham- mered steel tube plates into which are fitted lap-welded tubes (subjected to a similar test to those of the condenser) in such a manner that they can be readily withdrawn from the shell for inspection or renewal, and the whole is fitted in a tank with suitable brine-pump connections. The inlet and outlet tubes are likewise of forged steel. This arrangement is also patented. The makers prefer the use of sets or series of tubes in their condensers, and refrigerators, to that of coils or worms, for the following reasons. That coils or worms are usually made in long lengths with a number of welds, consequently should such a tube at any time exhibit signs of weakness it would entail a heavy expense to renew it, both on account of the weight of metal and the difficulty of replacement. In a refrigerator, in addition to the above^ the use of a coil gives rise to a tendency to prime, and thus cause damage to the pump, and there is, moreover, considerable trouble in bringing the brine into such intimate contact with the outer surfaces of the tubes as is advisable. When desired, an arrangement can be fitted to this a.mmonia compression machine, by means of which the ammonia can be pumped from the refrigerator into the condenser or vice vei'sa^ or, if desired, out of the machine altogether. An advantage of no small importance possessed by this apparatus is that of the utmost simplicity of construction, thus considerably facilitating the management. The workmanship and design, moreover, are calculated to ensure the attainment of the greatest strength and of the maximum durability possible. Fig. 26 is a perspective view illustrating a small single-acting vertical ammonia compression machine constructed on the Kil- bourn system; Fig. 27 is a similar view showing a pair of large double-acting horizontal machines ; and Fig. 28 is a perspective view showing another pattern of horizontal machine. In the installation shown in Fig. 26 the machine is driven by a gas-engine of 4 horse-power nominal, and it is designed for cold storage on the direct expansion system. The floor space occupied is small, being only for the entire plant 1 2 ft. by 4 ft. 6 in., and the machine is capable of maintaining a storage capacity of from 8,000 to 10,000 cubic ft. at a suitable tem- perature for frozen mutton, or, with the necessary appliances^ of making from 2\ tons to 2 tons of ice per twenty -four hours, 64 REFRIGERATING AND ICE-:\rAKING ^lACHINERY. THE COMPRESSION PROCESS. 65 66 REFRIGERATING AND ICE-MAKING MACHINERY. The condenser and refrigerator are composed of lap-welded iron coils fitted in steel or wrought-iron shells. The double-acting horizontal ammonia compression machines, shown in Fig. 27, are each driven by a vertical engine, which is fixed upon the same base or bed-plate in such a manner as to render the complete machine very compact in design, one of sufficient power to keep a storage capacity of 22,000 to 26,000 cubic ft. at a suitable temperature for chilled beef, 40,000 to 44,000 ft. for frozen mutton, or of making about 6 tons of ice per day of twenty-four hours, requiring only a floor space of 10 ft. by 10 ft., including that required for both the refrigerator and condenser. The compression cylinders are inclosed in water-jackets, and are fitted with Webb's patent arrangement of suction valves. The stuffing-boxes and glands are of the Kilbourn double pattern, that is, each box is formed with a chamber placed centrally therein, and into which oil is injected constantly for sealing purposes by a small force-pump fixed on the side of the bed-plate, and worked, as shown in the drawing, from a lever connected to the compression pump crosshead. The steam-cylinder piston-rods are coupled by means of forked connecting-rods to the same crank-pins as those of the com- pression pumps. These machines are suitable for either land 01 marine installations, and are similar to those fitted on board tot Cunard steamships Campania and Luca?na, a description and illustration of which will be found on pages 182-185. An improved form of gas-tight joints and stop-cock or valve, which will be found described and illustrated on page 154, have been also devised, and were patented in 1882 by the same inventor. The arrangement of the machine illustrated in Fig. 28 is very compact, having been just recently designed with that end more especially in view, and for which purpose the ammonia condenser is placed underneath the compressor. The main features of novelty claimed in the ammonia com- pression apparatus, invented by Thomas Bell Lightfoot, for which he obtained a patent in 1885, are as follows : — First, a combined refrigerating and ice tank, in which moulds are arranged between coils or pipes through which a vaporised freezing medium is caused to circulate, the said moulds and pipes being surrounded by brine or uncougealable fluid, not mechanically circulated. Second, a condenser, comprising coils or zigzag pipes, arranged within a zigzag passage or pas- THE COMPRESSION PROCESS. 67 sages formed in a tank or vessel, the arrangement being such that the vapour or gas to be condensed travels in a zigzag course m one direction, whilst the cooling fluid travels in the contrary direction, also in a zigzag course,' and in contact with the outer surfaces of the pipes in which the vapour or o-as is travelhng m an opposite direction. Third, a refrigerator^'com- prismg coils or zigzag pipes arranged within a zigzag passage or passages formed in a tank or vessel, the arrangement being such that the refri- gerating medium enters the coils or zigzag pipes at the bottom, the vapour being drawn off by the pump at the top, while the water fluid to be cooled enters at the top of the tank, and after travelling along the whole length of each coil or zigzag is drawn off at the bottom. P'ourth, a pump for compressing condens- able gas or vapour in which compression is effected at one side only of the piston the other side being exposed merely to the pressure of the vapour as drawn in from the refrigerator the suction valve being placed concentrically within the piston and the delivery valve within the cylinder cover The main distinctive feature of the Pictet machine is the means adopted for preventing superheating of the ammonia gas during compression in the cylinder of the pump and the loss that would ensue therefrom, which, were there no means employed for its reduction, might amount to as much as 30 per cent. ma_ double-action compressor. In some arrangements provision is made for effecting this by injecting a small quantity of hqmd into the compressor, which liquid in evaporating maintains the gas or vapour in a condition of saturation, therebv admittmg of the compression being effected under such condi- tions as to approximate more closely to the isothermal function • m others, again, the compressor cylinder is water-jacketed for a hke purpose. In the Pictet machine, however, in addition Fia. 28. 68 REFRIGERATING AND ICE-MAKING MACHINERY. to a water-jacket round the compressor cylinder or barrel, the piston and piston-rod of the compressor are likewise formed hollow, and through this space a constant stream of water is kept circulating for cooling purposes. The results obtained by this arrangement are much lessened by the great thickness of metal that is required in the parts. The loss in a well-jacketed and water-cooled compressor, according to the experiments^ of Professor Denton, amounting to 2 1 '4 per cent., and where less efficiently jacketed the loss will be from 21*3 to about 25 per cent. In the specification of a patent granted to Raoul Pictet in 1887 he describes an improved vessel or compartment for use in a refrigerating apparatus, wherein the volatile liquid employed is subjected to evaporation so as to produce cold, which refri- gerates brine or other non-congealable liquid surrounding the evaporating compartment. The said improved cooler or refri- gerator is claimed to be suitable for use with either a com- pression or an absorption machine, and consists of two tubes arranged horizontally and connected at their extremities by bent tubes, and at their lower sides by pendent U-shaped tubes, which latter are preferably secured by means of solder joints to sockets brazed on the tubes, and are further connected with each other by conducting bands. In the latter part of 1887 a patent was obtained by Samuel Puplett and Jonathan Lucas Rigg for improvements in refri- gerating machines, and several further improvements have since been added by Puplett. The main features of the 1887 patent, which are equally applicable to any ice-making and cooling apparatus wherein any one of the condensable gases is used as a frigorific agent, are as follows : — The provision ot chambers or reservoirs either situated directly at the bottom of, and communicating with the inlet valve chests, or in any other suitable position, and connected thereto by means of pipes. These chambers or reservoirs serve to receive the oil which finds its way into the cylinder of the compressor pump, principally round the piston-rod, and which would otherwise accumulate beneath the valves. To the undersides of the said chambers or reservoirs are fitted draw-off cocks, by means of which the oil may from time to time be withdrawn whilst the machine is in motion, and with- * * Transactions, American Society of Mechanical Engiaeei-s," vol. xii. THE COMPRESSION PROCESS. 69 out any appreciable loss of gas or admission of air taking place. A separator, for retaining any oil that may pass over with the gas, consisting of a cylindrical vessel having a water-jacket through which a circulation of cooling waler is maintained, and provided centrally with two or more sheets or screens of wire gauze or perforated sheet metal, by which the said cylindrical vessel or chamber is divided vertically into two compartments. The gas from the compression pump is discharged into this vessel or chamber against the sheets or screens, and is forced through the interstices or meshes, the surface contact separating the oil, held in mechanical suspension, from the gas. The separator being maintained at a lower temperature than the gas by means of the above-mentioned water-jacket, a rapid con- densation of any oil passing over with the gas takes place, and this oil is first deposited on the sheets or screens, from which it falls to the bottom of the separator, from whence it can be drawn off through a discharge-cock fixed therein, without stop- ping the machine, and without any material loss of gas or admission of air occurring. To catch any oil that may pass down the return-liquid pipe an interceptor is attached to the latter in any convenient posi- tion, but preferably as near as possible to the refrigerator. This interceptor is formed of a cylindrical vessel having a diaphragm extending from the cover to within a short distance of the bottom, and another diaphragm extending from the bottom thereof to within a short distance of the cover, thus forming three compartments. The return-liquid pipe passes through the cover nearly, but not quite, to the bottom of the interceptor on one side of the first diaphragm — that is in the outer com- partment — and is continued from near the bottom of the inter- ceptor to beyond the second diaphragm, that is to say, out of the third compartment. Any oil that passes down the return- liquid pipe collects in the first compartment of the interceptor, from whence it can be withdrawn through a cock fixed in the said first compartment without stopping the machine, or caus- ing an appreciable loss of gas or the admission of air to any injurious extent. This interceptor is preferably jacketed, and is surrounded with, and maintained at a suitable temperature by means of cold brine, in order to aid in separating the oil from the hquefied gas. Complete liquefaction of the gas is ensured by carrying the return-liquid pipe between the condenser and refrigerator 70 REFRIGERATING AND ICE-MAKING MACHINERY. through the refrigerating or ice-making tank or box, instead of outside the latter, as is usually done, thus utilising the low tem- perature of the brine to complete the condensation of the gas. The stop-cocks or valves for regulating, or completely cut- ting off or arresting, the flow of the gas or liquids to the various parts of the apparatus have metal seats. To prevent leakage of the gas or liquid, the stufhng-boxes of these valves are pro- vided with screwed glands, which are likewise screwed on to the valve spindles, which latter are screw threaded for their entire length, and are packed with some suitable yielding fibrous or metallic packing, such, for instance, as hemp or lead. This packing is caused to enter into the screw-threads upon the spindles as the glands are forced or screwed down, thus making Fig. 2Q. gas-tight joints round the latter, without causing the valves to set fast. The very considerable improvements which have, as already mentioned, been since added by Puplett, are illustrated in Figs. 29, 30, and 31, which show three of his latest pattern machines, viz., a marine type of horizontal compressor with vertical engine, an arrangement especially designed for use in breweries for cooling worts and yeast rooms, and lastly a hori- zontal machine intended more particularly for marine work. Tvlachines of the pattern shown in Fig. 29 are made in sizes THE COMPRESSION PROCESS. 71 varying from the smallest with an equivalent of ice made per day of 5 cwt., capable of maintaining a properly insu- lated room of 1,000 cubic ft. at 20° to 25^ Fahr., consum- ing one nominal horse-power, and occupying a floor space of 5 ft. by 6 ft., up to the largest, which has an equivalent of ice j^ig. 30. made per day of 480 cwt., is capable of maintaining a pro- perly insulated room of 160,000 cubic ft. at the said tempera- ture, requires a driving-power of 40 nominal horse-power, and occupies a floor space of 20 ft. by 20 ft. The cooling capacity of the machine shown in Fig. 30 varies from 20 barrels of worts per day to 200 barrels per day, and the horse-power required 72 REFRIGEIIATING AND ICE-MAKING MACHINERY. from 3 up to 12, in accordance with the size of the machine. The apparatus can be connected to existing hot and cold h'quor backs and collecting tanks. Sir Alfred Seale Ha slam took out a patent in 1894 for an improved compressor especially intended for use with refrigerat- ing machines, and particularly applicable to compound com- pressors wherein the gas is compressed in stages. The objects of the invention are to prevent the gas from escaping or coming in contact with the air, and to avoid dead spaces in the appa- ratus. The chief novel features are claimed to be as follows : — First, a pump cylinder having a chamber at one or both ends through which the piston -rod passes, and which is kept supplied Fig. 31. with lubricating and sealing liquid from a reservoir througli wdiich the gas to be compressed also passes. Second, two single and double-acting pumps arranged tandem to each other, and with the compression ends of their cylinders next each other, and having between them a chamber supplied with lubricating and sealing liquid, through which their common piston-rod passes. Fig. 31(7 shows the improved machine in plan and side elevation, and Fig. 31^ is a vertical central sec- tion through one of the ammonia compressors, drawn to an enlarged scale, illustrating the self-sealing oil chamber. The operation of Haslani's improved compressor is as follows : — After adjusting the glands of the receiving and sepa- rating vessel, the latter, and the central chamber, is charged with lubricating and sealing fluid to a suitable height. The gas is then drawn through the supply pipe, accompanied by the THE COMPRESSION PROCESS. 73 requisite amount of the lubricating and sealing fluid, which latter is admitted to the low-pressure cylinder by a cock or valve, through the suction-valve, and compression to the desired extent is then carried out. 74 REFRIGERATING AND ICE-MAKING MACHINERY. Another patent was taken out in the begin- nmgof this year (1895) by Sir A. S. Haslam for an improved appa- ratus for coohng air to be circulated through jooms or stores. The main feature of this in- vention consists in the provision of an air- cooler or chamber, wherein the air or other gas to be cooled is car- ried between a number of fixed vertical metal plates, down which cold brine or other uncon- gealable liquid is con- stantly caused to flow. These plates or dia- phragms are, as shown in the plan. Fig. 3 if, which illustrates an ar- rangement for use in connection with a meat chaml';er, prefer- ably of a corrugated form, and their lower extremities are placed either in or above a receiver for the liquid which trickles down their surfaces. To maintain the plates or diaphragms at suitable distances apart, and parallel one with the other, distance-pieces or blocks are placed between them at the top and bottom, which distance - pieces have lugs or recesses on their sides to provide THE COMPRESSION PROCESS. 75 passages for the liquid. The tops of the upper distance- pieces form the bottom of a tank suppHed with the cold liquid, and from which it flows down the plates in thin streams ; and they have, moreover, vertical projections at each end, which together form the ends of the tank. Above this tank are situated suitable numbers of troughs or pipes, and a shower of brine at a low temperature, drawn or lifted from the re- ceiver below, in which it is cooled by a pump or otherwise, is distributed over the bottom of the upper tank, from whence it trickles down the surfaces of the corrugated or other plates, or diaphragms. Through the spaces or clear- ances provided between these plates a current of air is driven by means of a fan or blower, the blast being divided by the said corrugated plates into a number of thin sinuous currents, and being reduced to a very low temperature by impinging against their surfaces and the cold fluid trickling down their sides. It has been found in practice to be prefer- able to place the above-described plates or diaphragms as close together as can possibly be done without injuriously checking the flow of air. Flat plates, or plates with horizontal corrugations, are not found to be so advantageous, because the air can pass between them in a straight line, instead of being compelled to wind back- wards and forwards between the corrugations and impinge again and again against the cold liquid and the surfaces of the plates ; in the case of flat plates, moreover, they have to be much thicker in order to insure the requisite stifthess. Both the compound-ammonia compression apparatus shown in Figs. 31^ and 31Z', and the cooling battery illustrated in Fig. 31^, are said to have given very favourable results under most exhaustive tests. A view (Fig. 31^) is given in the frontispiece illustrating in sectional elevation a small ammonia machine with the patent brine-cooling battery, for refrigerating air in large quantities, to be blown or forced into the room or chamber, which latter is also shown in vertical section on the left-hand side of the drawing. The Boyle compressor is of the vertical single-acting type, compressing on the up stroke only, and the extreme lower part of the cylinder forms an oil-chamber to seal the stufling-box. The gas is admitted freely below the piston for cooling purposes. The St. Clair compressor is of a compound form, being a 76 REFRIGERATING AND ICE-MAKING MACHINERY. combination of two or more single-acting compressors in such a manner that the gas is partly compressed at a lower pressure '/In 1 in one compressor, and then passed to another, wherein the higher compression is applied. CHAPTER VI. Management of Ammonia Compression Machines. Every particular type of machine working on this principle has, as a rule, certain distinctive or characteristic features, and will, of course, so far at least as these are concerned, require special care and adjustment, and it would consequently be totally impossible to lay down an arbitrary set of rules for working, that would be suitable to all ; nor is this necessary or required, as full particulars relating to the manipulation of each particular machine are invariably suppHed by the makers. The following points, however, are more or less applicable to all machines working on the ammonia compression principle, and should therefore be familiar to those in charge of samie. Before charging an empty machine with anhydrous ammonia, all air must first be carefully expelled. This is effected by work- ing the pumps so as to discharge the air through special valves which are usually provided on the pump dome for that purpose. The entire system should have been previously to this thoroughly tested by working the compressor, and permitting air to enter at the suction through the special valves provided for that purpose, and it should be perfectly tight at 300 lbs. air pressure on the square inch, and should be able to hold that pressure without loss. Whilst testing the system under air pres- sure it should be also carefully blown through and thoroughly cleansed from all dirt, every trace of moisture being also removed. It is totally impossible to eject all air from the plant by means of the compressor, therefore it is advisable to insert the requisite charge of ammonia gradually and not all at once, the best practice being to put in from 60 to 70 per cent, of the full charge at first, and cautiously permit the air still remaining to escape through the purging-cocks with as little loss of gas 78 REFRIGERATING AND ICE-MAKING MACHINERY. as possible, subsequently inserting an additional quantity of ammonia once or twice a day, until all the air has been got rid of by displacement; and the complete charge has been introduced. To charge the machine, the dryer or dehydrator of the appa- ratus for manufacturing or generating anhydrous ammonia, or where no such apparatus is included in the installation, the drum or iron or steel flask of anhydrous ammonia should be connected, through a suitable pipe, to the charging valve ; the expansion valve must be then closed, and the valve communi- cating with the dryer or dehydrator, or that in the flask or bottle opened. The machine should be run at a slow speed when sucking ammonia from the drier, or whilst the flask is being emptied, with the discharge and suction valves full open. In the latter case, when one of the said flasks or bottles has been completely emptied it must be removed, the charging-valve having been first closed, and another placed in position, until the machine is sufficiently charged to work, when the charging- valve should be finally closed, and the main expansion valve opened and regulated. A glass gauge upon the liquid receiver will show when the latter is partially filled, and the pressure gauges, and the gradual cooling of the brine in the refrigeratoi (in the case of a brine circulation or ice-making apparatus), and the expansion pipe leading to the refrigerator coils becom- ing covered with frost, indicate when a sufficient amount to start working has been inserted. It is sometimes advisable to slightly warm the vessels or bottles containing the anhydrous ammonia by means of a gas jet, or in some other convenient manner, whilst transferring their contents to the machine, as otherwise if frost forms on the exterior of the said bottles they will not be completely dis- charged, and loss of ammonia will ensue. The flasks, bottles, or other receptacles containing the anhydrous ammonia should be always kept in a tolerably cool and a perfectly safe situation, and they should moreover be moved and handled with the utmost caution and care. In the event of an accident occurring, and any consider- able quantity of the ammonia becoming spilt, it is well to remember that it is so extremely soluble in water that one part of the latter at a temperature of 60° Fahr. will absorb some 800 parts of the ammonia gas, therefore water should be employed to kill or neutralise it, and any person attempting to penetrate an atmosphere saturated with this gas should not fail to place a cloth well saturated with water over his nose AMMONIA COMPRESSION MACHINES. 79 and mouth. See table on page 258 for solubility of ammonia in water. The machine having been started, and the regulating valve opened, it is essential to note carefully the temperature of the delivery pipe on the compressor, and if it shows a tendency to heat then the said regulating valve must be opened wider; whilst, on the contrary, should it become cold, the said valve must be slightly closed, the regulation or adjustment thereof being continued until the normal temperature of the said pipe is the same as that of the cooling water leaving the condenser. When the charge of ammonia in the machine is insufficient, the said delivery pipe will become heated, and that even when the regulating valve is wide open. There are many additional signs of the healthy working of the apparatus other than the fact that it is satisfactorily per- forming its proper refrigerating duty, which soon becouie easily recognisable to those in charge ; for example, every stroke of the piston will be clearly marked by a corresponding vibration of the pointers or indexes of the pressure and vacuum gauges. The frost visible on the exterior of the ammonia pipes leading to and from the refrigerator will be about the same. The liquid ammonia can be distinctly heard passing in a con- tinuous and uninterrupted stream through the regulating valve. The temperature of the condenser will be about 15^ higher than that of the cooling water running from the overflow. And finally, the temperature of the refrigerator will be about 15° lower than the actual temperature of the brine or water being cooled. Air will find its way into the system through leaky stuffing- boxes, improper regulation of the expansion valve, &c. Its presence in any considerable volume is shown by a kind of whistling noise, the liquid ammonia passing through the expan- sion valve in an intermittent manner, a rise of pressure in the condenser, and also loss of efficiency thereof, and other obvious signs. In this case the said air must be got rid of through the purging-cocks in a similar manner to that which remains in I he system when first charging the machine. The presence of any considerable amount of oil or water in ihe system, which may result from careless distillation, will cause a reduction in efficiency, and will be evidenced by shocks within the compressor cylinder. The temperature can be regulated either by running the machine at a higher speed or by increasing the back pressure, 8o REFRIGERATING AND ICE-MAKING MACHINERY. or by a combination of both. Tiie back pressure can be regu- lated by means of an expansion valve w valves fitted between the receiver and the refrigerator evaporating coils or pipes in the main liquid pipe. Fig. 32 is a view partly in vertical central section showing a very common form of expansion valve of the taper spindle type, which is adapted for use with a manifold. The construction of this valve will be obvious from the drawing. Fig. 33 is a p'an, Fig. 34 is a vertical central section, and F'&- 35 is a view of the plug partly in vertical section through the port or v/ay, shewing the De La Vergne improved expansion cock, for regulating the f-ow of the liquid ammonia into the expansion coils. The port or passage through the plug (Figs. 34 and 35) is so formed as to admit of the nicest regulation being et!ected. With this object the round hole is not carried completely through the plug, but only through about three-quarters the thickness thereof, as shown in Fig, 35, and the remaining thin bridge of metal is perforated in the shape of a very narrow wedge as shown in Fig. 34. The plug is rotated by means of a worm and worm wheel in the manner which can be clearly seen from the drawing, and whereby very fine or delicate adjustment can be readily im- parted thereto. The narrow wedge-shaped passage or aperture AISIMONIA COMPRESSION ISIACHINES. 8 1 Fig. S2 REFRIGERATING AND ICE-MAKING MACHINERY. allows of the flow of the liquid ammonia being regulated to the minutest possible amount, the point or apex thereof being the first to open. A brief account of Puplett's regulating or expansion cock or valve has been already given on page 70 when dealing with Puplett and Rigg's 1887 patent, and a description of the Pontifex valve will be found on page 107, being one of the improvements included in his 1887 patent. It is absolutely necessary that an ample supply of oil for Fig. 3^. lubricating purposes be forced into the stuffing-box of the compressor at frequent intervals, otherwise it will be found that the heated ammoniacal gas at high pressure will very rapidly cut through even the very best packing. Pure mineral oil of good body is found to be the best lubricant ; animal and vege- table oils should not be used, as, on contact with ammonia, they will saponify, and much trouble and loss will ensue therefrom. Another matter requiring special attention is the proper lift of the suction and discharge valves, and these should in- variably be provided with proper means for admitting of the high lift being readily adjusted. The lift should not be too otherwise the said valves will not close with sufficient promp- titude, and a loss of efficiency will result, and that more espe- cially in compressors running at a high speed. AMMONIA COMPRESSION MACHINES. 83 When superheating of the ammonia gas in the compressor is guarded against by the circulation of cooHng water through a jacket surrounding the latter, it is desirable to ascertain the proper amount of water necessary to secure the best results. This will, of course, vary with the condensing pressure, about 12 gallons of w^ater per hour for each ton of refrigerating effect per day of 24 hours being usually found to be sufficient for low condensing pressures of, say, from 95 to no lbs., whilst, on the other hand, with a high condensing pressure of about 150 lbs., the amount will have to be increased to 50 gallons or more per hour. The larger the amount of cooling water that is employed in the separator jacket the better; and this water need not be wasted, as it may be conducted through a suitable overflow into the condenser, and utilised together with that delivered specially thereto. The overflow pipe conducting th:s water to the condenser should preferably dip down for a certain dis- tance into the said condenser. Respecting the quantity and temperature of the cooling water for the condenser, it must be remembered the lower the temperature of the condensed ammonia the less will be the pressure against which the compressor has to work, and con- sequently the greater will be the saving in fuel and in wear and tear to the moving parts. The amount of condensing water required will vary in accor- dance with the temperature at which it is run from the con- denser ; for instance, if the condensing water be run into the said condenser at a temperature of about 60° Fahr., and leaves at the overflow or waste at a temperature of say 90° Fahr., the quantity of water required will be about i gallon per minute for each ice capacity of one ton per twenty- four hours ; whilst if the temperature of the overflow or waste were 75° Fahr. the original temperature at the inlet being the same as before, the amount of water required would be about 2-5 gallons per minute for each ice capacity of one ton per twenty-four hours, and a reduction of about 40 lbs. in the condensing pressure would be effected. In large towns and cities, however, where the water from the water companies' mains has to be used, and paid heavily for, it is often doubtful economy to attempt to reduce the tempera- ture of the condensed ammonia below a certain point, say 60° Fahr., during the winter months, and 70° Fahr. during the summer months. It is obvious that when a high price has to 84 REFRIGERATING AND ICE-MAKING MACHINERY. be paid for the water employed for cooling and other pur- poses, every effort possible should be made to utilize it to the fullest extent, and, with this end in view, it is desirable to use the overflow water from the condenser for boiler-feeding pur- poses, or to employ some means, such as a cooHng tower, for saving that which would be otherwise run to waste and be completely lost. An efficient and economical arrangement for this latter pur- pose is Puplett's improved water-saving and cooling apparatus, which is illustrated in Fig. 36. It is claimed by the inventor that the use of this contrivance enables the condensing water to be used over and over again with comparatively little loss, the waste indeed being practically confined to the quantity taken up by evaporation, which loss is, of course, more con- siderable in hot weather, and the consumption of condensing and circulating water is thus minimised as much as possible. It is stated to have been clearly demonstrated that in regular working for a considerable period, with a temperature in the sun of 93° Fahr,, the entire loss experienced did not exceed 3 per cent, of the total quantity of water circulated. The ccst of the up-keep of the apparatus, moreover, is trivial, being one farthing per thousand gallons cooled, and the power required under ordinary conditions is one horse-power indicated for the same amount. To prevent loss of efficiency from heating of the condensed ammonia, it is advisable that the receiver and piping should be covered with a thick layer of some suitable non-conducting material, which precaution is the more necessary, inasmuch as the said piping generally passes through the engine-room, and consequently the temperature of the ammonia is not infrequently raised as much as 25° above that at which it left the condenser, before it enters the coils or pipes of the refrigerator, which causes a loss of about 2*5 per cent, on the ice-making capacity of the machine. The pipes con- veying the ammonia gas from the coils or pipes of the re- frigerator to the compressor should be likewise well covered with non-conducting material, so as to prevent, as far as pos- sible, any further accession of heat in the said gas during the transit. The desirability of this will be readily seen when it is remembered that the refrigerating capacity of a machine of this type is dependent upon the weight of ammonia circulated, and that the volume of a given weight of the gas increases in pro- portion to the elevation of its temperature, and consequently AMMONIA COMPRESSION MACHINES. 85 the higher this is raised the smaller will be the weight of the gas circulated or dealt with by the compressor, although the volume may be the same. In the case of a compressor wherein the cyHnder is cooled by a water circulation round the exterior walls thereof, and not by the introduction of cooling liquid to the interior thereof, a certain amount of the oil employed for lubricating purposes will gain access to the interior round the piston rod, and this oil would, unless proper means be taken to prevent it, be carried through the discharge valve along with the ammonia gas, and, after first passing into the condenser, would finally gain access to the evaporating or expansion coils or pipes of the refri- gerator, and also stop or clog up the expansion valve, and otherwise reduce the efficiency of the machine. The method employed for recovering any oil carried over with the ammonia gas in a compressor of the De La Vergne type, employing a sealing, cooling, and lubricating liquid in the cylinder, has been already mentioned (page 48) when dealing with that machine, with compressors wherein other means are employed for ensuring a complete or a practically complete discharge of the ammonia at each stroke of the piston, suitable oil separators or collectors for the mechanical separation of the oil from the gas, and in some cases rectifiers are used. The separator or oil collector frequently supplied consists merely in a cylindrical vessel into which the ammonia gas is conducted at one extremity and leaves at the other, the said inlet and outlet being situated at some inches from, the ends or covers, the gas is supposed to be freed from the oil carried over therewith by coming in contact with the sides of the cylinder, and it passes on to the condenser, whilst the said oil falls to the bottom of the vessel. A better form of separator is that wherein baffles or plates, de- scending vertically to slightly below the centre of the cylindrical vessel, and extending alternately nearly but not quite to the opposite sides thereof, are employed. In this arrangement the gas is admitted at one side of the cylinder and, after taking a zigzag course between the said baffles or plates, leaves at the other side thereof. A very considerable increase of contact surface is thus ensured in a separator of this type, a modified form of which is employed in the De La Vergne system, and the said separator is rendered considerably more efficient. The gas being at a temperature of some 200° Fahr. when passing through the separator or interceptor, the oil contained 86 REFRIGERATING AND ICE-^IAKING MACHINERY. or carried over therewith is in a limpid condition, and is, therefore, difficult to eliminate from the gas. To obviate this objection the separator or oil collector is sometimes water- jacketed, by which means the temperature can be maintained low enough to cause the oil to separate easily from the gas and fall to the bottom of the cyHnder or vessel. By this arrange- ment its efficiency is still further increased. Puplett and Rigg's patent separator or interceptor has been already described on page 69, and centrifugal oil separators have also been used with some success. Even the best of the ordinary separators or oil collectors at present in use, however, are more or less defective in action. Fig. 37 shows a modified arrangement of the catch-alls or inter- ceptors employed on the Yaryan patent evaporators, which would, in all probability, ensure a more perfect elimination of the oil. As will be seen from the illustration it consists in a cylinder a, which is water-jacketed as shown at a\ and divided into two compartments by a tube-plate or partition b, from which project tubes c, c, which extend round the gas outlet pipe d, and extend nearly but not quite to the end of the cylinder, the said outlet pipe extending mto the cylinder for a distance equal to about half the length of the tubes, e is the inlet pipe through which the ammonia gas and the particles of oil carried over therewith are delivered into the first chamber of the separator or oil col- lector, F is a wire gauze or perforated screen or diaphragm, and AMMONIA COMPRESSION MACHINES. 87 f\ f\ are baffle or check-plates which extend alternately to within close proximity to the opposite sides of the cylinder. A clear- ance is likewise provided at the bottom of each of the said baffle or check-plates f, and of the partition or tube-plate b, to allow the free passage of the oil from the first compartment or chamber to a well formed in the bottom of the separator cylinder a : G is a pipe leading from the said well, through which the oil can be drawn off when required ; H, h\ are respectively the inlet and outlet pipes for the cooling water to the water-jacket. In operation the gas and oil enter the first chamber or com- partment of the separator, and pass to the tubes c, through the wire gauze diaphragm f, and taking a zigzag course from side to side of the separator past the baffle or check-plates f\ A large proportion of the oily particles strike against the sai.d diaphragm, and the check, division, or baffle-plates f\ and- become separated from the gas, finally falling to the bottom of the compartment and passing to the well a^. The partially cleared gas then passes through the interior of the open-ended tubes c into the second chamber or compartment, and returns along the space on the outside thereof to the outlet pipe d, the remainder of the oily particles becoming deposited on the interior and exterior surfaces of the tubes c, and on the walls of the compartment, from which they Hkewise fall, and are collected in the well in the bottom of the latter. The very extended surfaces with which the gas thus comes in contact during its passage through the separator or collector, will ensure the complete deposition of the oil held in suspension by the gas, and the said gas will finally pass out from the separator or oil collector at the oudet pipe d completely, or practically completely, freed therefrom. The separator or oil collector is sometimes so connected with the compressor that the oil can be used over again ; this, how- ever, is objectionable in the case of a double-action compressor, as the connection is liable to become choked with pieces of packing that find their way into the separator. When a rectifier is used, the separator is in some instances connected therewith through a rotary cock, operated from the main shaft by means of a band, which cock is kept constantly working discharging a small quantity of oil at each revolution into the rectifier, so long as any remains in the separator. The failure of oil in the separator is indicated by the connecting pipe between the latter and the separator becoming covered with frost, when the cock must be immediately thrown out of gear and the oil allowed 88 REFRIGERATING AND ICE- MAKING MACHINERY. to accumulate in the separator before restarting it. When the separator is connected directly with the rectifier the cock in the connecting pipe should be opened periodically, say about every twelve hours. The oil may be discharged from the rectifier at about similar intervals, and the amount of oil that is found to be entering the compressor cylinder is an index to the state of the packing in the stuffing-box, a large quantity being a certain sign that it requires renewal or seeing to. It is most important that the separator or oil collector be cleaned out at pretty frequent and regular intervals. It not infrequently happens that deposit accumulates on the exterior surface of the condenser coils from sediment in the water, and on the interior surface thereof from oil and foreign bodies. Tlie smaller ammonia pipes may sometimes become filled with obstructions to the extent of completely blocking them up. These bodies may consist of lumps of solder or other matter accidentally left in the tubes when making the joints, or of pieces of packing from the stuffing-box carried over with the gas. The deposit or furring of the condenser coils or pipes is objectionable inasmuch as it acts as a non-conducting covering, and prevents them from freely transferring the heat to the cooling water, and the choking of other conduits is likewise followed by corresponding loss of efficiency, for example, that of one of those leading to one of the refrigerator coils or sets of pipes will result in the latter not acting at all, or only very slightly. Complete choking up or obstruction of one of these latter conduits is evidenced by that particular pipe, and also the corresponding return pipe, not becoming covered with frost at all, or only so to a very small extent; and a slightly less degree of frost upon any of these pipes indicates partial choking or obstruction, and a consequent very feeble action of the said coil or set of pipes. The coils or pipes in the condenser should be frequently cleaned on the exterior with a suitable brush, and whenever practicable removed at fixed periods and carefully scaled. This is best and most easily effected by heating the tubes, care being taken however not to carry such heating to an injurious extent. The interior surfaces of the tubes can be cleansed by blowing steam through them at a considerable pressure. To clear small obstructions from a conduit leading to one of the refrigerator coils or sets of pipes, it is usually sufficient to turn the entire stream of ammonia into it Should, however, the said obstruc- tion prove obstinate, and it be found impossible to shift it in AMMONIA COMPRESSION MACHINES. 89 this manner, an early opportunity must be taken to clear it by blowing steam through it. Any considerable choking of the conduits leading to the refrigerator coils is followed by a very marked decrease of efficiency in the latter. Whenever a joint has to be broken, and any portion of the machine opened for any purpose whatever, it is absolutely essential that the whole of the ammonia contained in that part should be pumped or transferred to another part, or if this can- not be done it should be discharged, preferably into water, which can readily be effected by means of a short strong india-rubber tube. On account of the already-mentioned great solubility of ammonia in water, it will become readily absorbed, if the vessel into which it is discharged be kept sufficiently replenished with cool water. It is of the utmost importance that the rule of carefully removing all ammonia pressure before breaking a joint be strictly adhered to. In warm weather, or in hot climates, the joints will require constant attention, and periodical inspection, and tightening up of the bolts; and at all times, even in the winter in this climate, they are liable to develop leaks through the working of the machinery. Ammonia being a good solvent, and having no effect upon iron or steel, the parts will become clean and free from deposit, after working for a short period, and the cylinder and piston will be found highly polished. Ammonia also possesses some slight lubricating qualities, and, therefore, after starting, no other lubricant need be introduced into the compressor cylinder. The cylinder covers, as also the valve box covers, should be occasionally removed and a thorough inspection made of the piston, cylinder, and valves. The latter are exceedingly apt to become cut or marked by fragments of scale, and require grinding in periodically. A properly packed piston-rod will remain in good order for at least six months, provided the said rod be in first-rate con- dition and perfectly true ; under contrary conditions, however, trouble will be experienced in a fortnight, or less. The usual precautions to be observed in order to properly pack a steam- engine or other stuffing-box, which are well known, or should be so, to those in charge of ammonia plants, are equally applic- able in the case of the compressor, but the hereinbefore-men- tioned extensively searching nature of ammonia gas demands the exertion of extra care. These observations apply more especially in the case of a double-acting compressor where tile go REFRIGERATING AND ICE-MAKING MACHINERY. pressure upon the gland may reach i8o lbs. to the square inch. In a single-acting one, where the pressure should not exceed 28 lbs., this extreme care is not of so much moment, though it is, of course, still important to have a tight joint. The stuffing-boxes should be formed unusually deep, say about a foot, from ^ to f of an inch being left between the piston-rod and the interior of the box. For single-acting com- pressors metaUic packing will be found the best, that of Victor Duterne, the patent for which expired many years ago, being an excellent one for the purpose. Double-acting compressor stuffing-boxes should be packed with a combination of pack- ings, a perforated ring being placed between them, and many of the special and patented packings will be found suitable for the purpose. Plaited cotton packing cut into suitable lengths and inserted in the form of rings will also be found effective ; it is desirable, however, to finish off with one or two india- rubber insertion rings. The packing should be driven home tighdy, piece by piece, with a packing stick formed of hard wood, and a mallet, and the gland finally screwed on by hand only, so as to allow for the expansion of the said packing. This latter precaution is absolutely necessary in order to ensure the maximum life of the latter. When tightening up the gland care must always be taken to do so equally all round, and not to screw up the nut on one bolt more than on any of the others. To determine the efficiency of an installation on the am- monia compression system, the following fittings are required, viz. : — An indicator, so that diagrams can be taken from the compressor ; stroke counters, to enable the number of strokes made by the steam-engine and brine pumps to be ascertained ; and mercury wells to admit of the temperature being obtained at various points throughout the system. In making a test it is desirable that it should last at the very least for fully tw^elve hours, and it is better to carry it on for twenty-four hours. The number of readings which it is desir- able should be taken from the various instruments will vary in accordance with w^iether or not the work is steady or otherwise, and the person carrying out the test will have, of course, to use his own judgment on this head. Where artificial ice is made, for example, twice an hour wnll be sufficient, whilst on the other hand, four or more readings per hour should be taken in cases wdiere the variation in the temperature of the materials to be cooled is wide. Indicator diagrams should be AMMONIA COMPRESSION MACHINES. gi taken from both the steam-engine cylinder and the compressor cyHnder every two hours. A mercury well, for an horizontal pipe, when the latter is of sufficient dimensions, consists usually in a short piece of tubing closed at its lower end, and fitted into the pipe by means of a suitable bushing. It is filled about three parts full of mercury, and the thermometer, which should have an elongated cylin- drical bulb, is held in position therein by means of a perforated cork. For vertical pipes, or pipes of very small dimensions, where this arrangement would be impracticable, the well is generally formed by means of a w^ooden or other block, one side of which is shaped to the outline of the pipe to which it is to be applied, and has a suitable recess formed therein. This block is firmly secured against the pipe by metal straps in such a manner that a portion of the wall of the well will be formed by the pipe, the latter being scraped perfectly clean at that part. The joint between the block and the pipe must be made perfectly tight, which can easily be effected by means of a little white lead paint, there being no pressure, and the whole should be surrounded by a thick layer of non-conducting composition, through which the stem of the thermometer is permitted to project. The points in the system where it is desirable to locate the mercury wells are : — The suction pipe just at its connection with the compressor; the discharge pipe, as close as possible to its connection with the compressor ; the ammonia discharge pipe from the condenser, as near the latter as practicable. Where a brine circulation is employed: — The pipe or manifold supplying the various coils or sets of pipes in the refrigerator ; the dis- charge pipe of the refrigerator; the brine discharge pipe, at the point where it connects to the refrigerator; and the brine return pipe in proximity to where it connects with the refrigerator. Before closing this chapter, a few words upon the excess condensing pressure invariably found in ammonia compression machines will not be out of .place. This excess of the actual working condensing pressure over the theoretical is caused by the ammonia gas being imprisoned in the comparatively con- fined space afforded by the coils or pipes in the refrigerator, and the excess pressure is more marked in an horizontal com- pressor running at a high speed of, say, 140 revolutions per minute, than it is in vertical ones having only a low speed of from 35 to 60 revolutions per minute ; it varies, moreover, in almost every make of compressor. At a low suction pressure o^ 02 REFRIGERATING AND ICE-MAKING MACHINERY. about 15 lbs. it should not be more than lo lbs., but With a suction pressure of, say, 27 or 28 lbs. it may rise to 50 lbs., or even more. The condensing pressure affords a means of ascertaining whether or not the apparatus contains the proper full charge of ammonia, or if the losses sustained by leakage are sufficient to render it necessary to insert an additional supply. For this reason it is advisable for the person in charge to keep a record in a proper book, suitably rule^i for the purpose, of the tem- perature of the condensed ammonia when leaving the con- denser, and also of the condensing and suction pressures, at regular intervals of, say, three hours. This will enable him to follow the state of the ammonia charge, for example, if the condensing pressure is found to be gradually falling during a three months' period, as compared with the average condensing pressure of the previous three months, whilst at the same time the condensing temperature and the suction pressure remain constant, it will be evident that the charge of ammonia has become reduced by leakage to a sufficient extent to require replenishing. This reduction in the condensing pressure is caused by the diminution in the charge of ammonia giving larger condenser space, the gas having thus a much more extended worm, coil, or tube space wherein to condense and liquefy, and hence the decrease. As a general rule it may be taken that, whenever the condensing pressure is found to have fallen about 8 lbs., enough ammonia to restore the original condensing pressure should be inserted into the machine. CHAPTER VII. The Abstraction of Heat by the Evaporation OF a separate Refrigerating Agent of a Volatile Nature under the Direct Action OF Heat, which Agent again enters into Solution with a Liquid, or the Absorption Process. — The Binary Absorption Process. The principle involved in the operation of machines for the abstraction of heat by the evaporation of a separate refrigerat- ing agent of a volatile nature by the direct action of heat, and without the use of power, is, as has been previously observed of the liquefaction process, more a chemical or physical action than a mechanical one. It is founded upon the fact of the great capacity possessed by water for absorbing a number of vapours having low boiling points, and of their being readily separable therefrom again, by heating the combined liquid ; hence it is commonly known as the absorption process. The absorption process was invented by Ferdinand Carre (brother to Edmond Carre, whose sulphuric acid freezing apparatus has been previously mentioned), about the year 1850. This system involves the continuous distillation of ammoniacal liquor, and requires the use of three distinct sets of appliances, viz. : — Fu'st, for distilling, condensing, and liquefying the ammonia. Second, for producing cold, by means of a refrigerator, an absorber, a condenser, a concentrator, and a rectifier. Third, pumps for forcing the liquor from the condenser into the generator for redistillation. The three operations are each distinct from the other, but when the apparatus is in actual work they must be continuous, and are dependent upon one another, forming separate stages of a closed cycle. An advantage of the absorption process is that the bulk of the heat required for performing the work is applied direct 94 REFRIGERATING AND ICE-MAKING MACHINERY. without being transformed into mechanical power. The first machines, however, constructed upon this principle were very imperfect in operation, by reason of the impossibility of securing an anhydrous product of distillation, and as the ammonia distilled over contained as much as 25 per cent, of water, a very large expenditure of heat was required for evaporation, and the working of the apparatus, moreover, was rendered intermittent. This was owing to the distillation, which is the most important operation, and has of necessity to be executed in a rapid manner, being, in the first machines, very imperfectly eftected, and the liquor resulting therefrom being naturally much diluted with water. Another serious result of the above defect, Avas the accumulation of weak liquor in the refrigerator, and the consequent necessity for constant additions of ammonia. By subsequent improvements, however, made by Rees Reece in 1867-70; Mort in 1870, who introduced an improved temperature exchanger or economiser; H. F. Stanley, 1875; F. Carre (the original inventor), in 1876; W. H. Beck, in 1886; Mackay and Christiansen, and E. H. Tompkins, in 1887; and later still in the same year by E. L. Pontifex, the distillate has been rendered nearly anhydrous, and absorption machines have been brought to a very considerable degree of efficiency. In Fig. 38 is illustrated F. Carre's continuous acting absorp- tion machine. As above mentioned, the agent employed in this apparatus is ammonia. In the drawing a indicates the generator, b is the liquefier, c is the refrigerator, d is the absorber. Aqua ammonia is introduced into the gene- rator A, the level of the liquid being indicated by a gauge glass which is shown on the left-hand side of the said generator, and which is practically similar to that used on steam boilers, and the evaporation is effected by heat from the furnace shown beneath. The gas from the generator a is conducted by a suitable pipe e to the liquefier b, wherein it passes through a congeries or series of coils or zigzags arranged in a bath of cold water, which is kept constantly renewed from the reservoir f. By the time the ammonia has reached a vessel situated at the termination of the coils or zigzags in the liquefier it is in a liquid condition, and under a pressure of about 150 lbs. per square inch, which pressure is constantly maintained in the generator a. In the liquid state the ammonia flows through the pipe G to the regulator h, by which it is admitted to the distributor i THE ABSORPTION PROCESS. 95 through a pipe k, which latter is wound spirally round the o 9 2 pipe or tube l, which is of larger bore, and through which the vaporised or gasified ammonia returns from the refrigerator c, 96 REFRIGERATING AND ICE-MAKING MACHINERY. after having performed its heat-absorbing duties therein. By this arrangement the said returning vapour or gas is made to do some further work by absorbing or taking up heat from the liquid ammonia on its way to the refrigerator. The refrigerator represented in the drawing consists of a set or series of six or other suitable number of spiral or zigzag tubes c^, cS which return upon themselves, forming an equal number of partitions in the tank wherein they are immersed, which latter is constructed of suitable non-conducting material. Each of these zigzags receives an equal supply of the liquid ammonia from the distributor i, and the space in the insulated tank surrounding them is filled with some uncongealable liquid, or one that will congeal only at very low temperatures, such as alcohol, or a solution of chloride of calcium or of common salt, which is usually known as brine. The ice-cans or cases are immersed in the liquor between the zigzags, and are sustained upon a carriage capable of being moved by the same mechanism that works the pump m, by which the resaturated solution of ammonia and water is re- turned to the generator. The ammonia gas or vapour from the zigzags in the refrige- rator c is collected in the cylindrical vessel n, from which it passes up through the tube l to the absorber d, where it meets the water that has been brought from the bottom of the generator a, and which partiially fills the latter. This water being nearly free from ammonia, it having been exhausted therefrom by evaporation in the generator a, greedily absorbs or takes up the ammonia gas or vapour injected into it from the tube l. The absorber d is fitted with a worm d^ which receives cooling water from the supply tank f, and the water from the generator a, which is brought by the pipe o, is first passed through the coolers p, p^ before delivery into the absorber d, and is thereby cooled so as to fit it to absorb the ammonia gas or vapour in the said absorber d more freely. The transference of the water from the bottom of the generator a to the absorber d is effected by the pressure in the former, whenever the stop-cock or valve o^ in the pipe o is opened. The pipe o is carrie-d in a double coil through the cooler p, which consists of two concentric cylinders, and in a single coil through the cooler p^, discharging through a sieve, strainer, or perforated tray, in a fine shower into the absorber d. The strong ammoniacal solution from the absorber d, which is THE ABSORPTION PROCESS. 97 considerably reduced in temperature, is passed through the spaces round the coils of pipe o in the cooler p, and whilst reducing the temperature of the hot exhausted solution or water from the bottom of the generator a on its way to the absorber d, is itself raised several degrees before being returned to the said generator, to the mutual advantage of both. The coil of pipe o, in the second cooler p\ is water cooled from the supply tank f. The saturated solution from the absorber D is drawn off by the force pump m (which is driven by a steam-engine or other motor), through the pipe r, and is delivered tliereby to the space round the coil in the cooler p, passing from the said cooler, through the pipe x, to the dome on the upper part of the generator a, where it falls upon, and trickles downward through, a series of perforated strainers or trays, whilst the ascending ammoniacal gas or vapour, on the other hand, takes a sinuous upward course, alternately passing round the edge of one of the trays, and through a central hole or aperture provided in the next, and so on to the gas or vapour pipe e; any aqueous vapour, which might otherwise be carried off with the ammoniacal gas or vapour, being thus condensed and returned to the generator. The constant pressure maintained in the generator a is, as already mentioned, about 150 lbs. per square inch, and to prevent this pressure from being exceeded a safety valve is provided on the dome of the generator a. Any gas that escapes through this safety valve is led through a suitable pipe to a small water tank, where it is absorbed. As will be seen from the above description, the operation is shortly as follows : — The aqua ammonia is first introduced into the generator a, the gas or vapour expelled therefrom by heat into the con- denser b; and so that the process may be carried out continu- ously and not be arrested by the exhaustion of the solution, the exhausted or impoverished liquor is slowly drawn off at the bottom of the generator, an equal volume of fresh strong- solution being constantly inserted at the top thereof. The united effects of the cooling and pressure produce liquefaction of the ammoniacal gas or vapour in the condenser, and the liquid ammonia passes to the refrigerator. It will thus be seen, that, as the ammoniacal gas or vapour from the tubes of the refrigerator is re-absorbed, and a rich solution formed to feed the generator, the absorbing water used being that with- H 98 REFRIGERATING AND ICE-INIAKING MACHINERY. drawn exhausted from the latter, the said generator and the condenser will keep up a continuous supply of the liquid, and the refrigerator will continue to freeze successive charges of wafer in the ice-cans or cases, provided, however, that the requisite heat to vaporise or gasify the ammonia is supplied to the said generator. If, therefore, the entire apparatus be perfectly fluid tight, as it is theoretically supposed to be, no escape could take place by leakage or otherwise, and the same materials would go on indefinitely producing the same uniform effect. In starting a machine constructed on the absorption principle it must be first blown through to expel all the air. In Carre's apparatus the air escaping from the absorber is conducted by a suitable pipe into what is known as a purger, where it is passed below the surface of water to absorb or retain any ammonia that would otherwise escape therewith. A large amount of water is required for cooling purposes in the condenser or liquefier, and absorber, and a considerable consumption of fuel is also necessary to heat the generator, when this is performed directly by means of a furnace, as shown in Fig. 38 (page 95); when, however, this is effected by steam-heated pipes, as in Stanley's 1875 patent, or, as will be described later on, by coils of pipe heated by the exhaust steam from an engine, or even by direct or live steam from a boiler, there is a considerable saving on this head. Steam or other motive power is likewise required for driving the force pump. It is claimed by Mr. Carre that for each pound of coal consumed as fuel, from 8 to 12 lbs. of ice can be produced, in accordance with the size of the apparatus. For working the larger form of machine, capable of making 500 lbs. of ice per hour, two men are required ; the force pump is capable of forcing 220 gallons of liquid per hour into the generator, and during the same time TOO lbs. of pure ammonia is liberated from solution, liquefied, evaporated, and re-dissolved or re-absorbed. , Rees Reece's chief improvement is founded on the fact that two vapours having different boiling-points, when united, can be recovered by fractional condensation, and by means of his apparatus a practically anhydrous distillate can be obtained. The special feature in the invention described in his 1867 patent is the method of obtaining nearly anhydrous liquid ammonia by means of an anrlyser, a rectifier, and a condenser, ih<^ peculiar eonbtruction and arrangement of which enables a THE ABSORPTION PROCESS. 99 continuous distillation and rectification of a dilute solution of ammonia to be effected upon the separative principle. The ammoniacal gas is reduced by its own pressure to a liquid condition in the condenser, from which it passes into the refrigerator at a very low temperature, quickly abstracting the heat from any fluid passed through the latter. A boiler is connected with an analyser consisting of a series of plates arranged in the usual manner within a strong iron vessel. The analyser is connected with a rectifier, which is provided with a series of vertically arranged tubes surrounded by cold water, through which tubes the ammoniacal fluid passes to the condenser; or in an alternative arrangement the rectifier is provided with a series of vessels placed one above the other with a space between them, the said vessels being so connected that a passage is formed from end to end thereof for a continuous stream of cold water. The condenser is either fitted with tubes and is practically similar in construction to the first arrangement of rectifier above mentioned, or it consists simply of a cylindrical or other suitably shaped iron vessel, of sufficient strength to resist the internal pressure of the gas, and immersed in cold water. From this condenser the condensed ammonia passes to a refrigerator, which may be of any con- venient form and construction. The liquid cooled in the refrigerator parts with the greater portion of its heat to the condensed ammonia, which is again vaporised, and in this form passes into an absorbing vessel which is kept cool by water, and which serves to maintain the required vacuum in the refrigerator. The ammoniacal solution passes from the absorber into a heating vessel, from which it is returned into the analyser. The latter may, however, on occasions be dispensed with, and the boiler connected directly with the rectifier. In his 1870 invention further improvements are introduced, and the entire apparatus comprises a generator, an analyser, a rectifier, a liquefactor, a receiver, a refrigerator, an absorber, and a heater, an engine placed between the refrigerator and the absorber being sometimes, moreover, employed. The first five of these vessels form what may be called the distillery part of the apparatus, and the main object of these improvements is likewise to ensure the more perfect elimination of liquid ammonia in an anhydrous condition, or practically so, from its aqueous solution, and in one continuous uninterrupted •operation. 100 REFRIGERATING AND ICE-MAKING MACHINERY. The analyser consists of a vessel fitted with a series of perforated cups or dishes, a dividing plate, an overflow pipe, and a dead plate or baffle to prevent the direct passage of the steam through the cylinder. The absorber comprises a series of pipes arranged together within a tank or cistern. The ammoniacal gas eliminated from its soludon in water by the action of the generator, analyser, and rectifier, passes onwards to the liquefactor or liquefier, wherein by its own pressure it is reduced to a liquid, and is collected in the receiver; the liquid ammonia so obtained being practically anhydrous. This anhydrous ammonia is then passed into the refrigerator, in which is placed a coil of pipe, any liquid passing through which will be cooled by the evaporation of the liquid ammonia surrounding it. The refrigerator is connected through a stop-cock or valve to another coil contained or enclosed in an iron pipe, which coil extends to the absorber vessel, the latter being connected to the coil of piping contained in the refrigerator. The object of this second vessel and coil is to effect an interchange of temperature with the gas. During its furdier onward passage to the absorber the ammoniacal gas comes in contact with the spent or exhaust liquor of the distilling apparatus in which it dissolves, yielding back the original quantity of the ammonia solution, to be used over again repeatedly without any appreciable loss or waste. This solution of ammonia is forced by a pump into the top of the analyser, wherein the ammonia is separated from the water, and passes to the condenser to be liquefied, whilst, on the other hand, the exhausted liquor goes to the generator, and from thence into the temperature exchanger or heater, and on to the absorber. The tension or elastic force possessed by the gas as it passes from the refrigerator to the absorber, especially when employed for cooling water, admits of its being utilised for driving the pumps of the apparatus, or for other purposes. The operation of Reece's improved apparatus is briefly as follows : — ■ The charge of liquid ammonia (the ordinary commercial quality of a density of 26° Beaume) is vaporised by the application of lieat, and the mixed vapour of water and ammonia passed to the vessels called the analyser and the rectifier, wherein the bulk of the water is condensed at a comparatively elevated temperature, and is returned to the generator. The THE ABSORPTION PROCESS. 10 1 ammoniacal vapour or gas is then passed to the condenser, where it is treated in a substantially similar manner to that in Carre's apparatus, that is to say, it is caused to liquefy under the combined action of the condensation effected by the cooling water circulating round the condenser tubes, and of the pressure maintained in the generator. The liquid ammonia (in this case practically anhydrous) is then used in the refrigerator, and the vapour therefrom, whilst still under considerable tension, is admitted from the refrigerator to a cylinder fitted with a slide valve, and entry and exhaust ports, practically similar to those of a high pressure steam-engine, and is thus utilised to drive the force pump for returning the strong solution to the gene^ rator, after which it is passed into the absorber, where it meets, and is taken up by, the weak liquor from the generator, and the strong liquor so formed is forced back into the generator by means of a force pump as before described. The temperature exchanger or economiser introduced by Mort in 1870, provides for the hot liquor on its way from the generator to the absorber, giving up its heat to the cooler liquid from the absorber on its way to the generator, thereby saving the abstraction of so much heat from the generator, and admitting of the liquid in the absorber being kept at a lower temperature, which is of great importance to the economical working of the apparatus. The invention which Harry Frank Stanley patented in 1875 comprises several important improvements upon the foregoing^ the chief of which are as follows : — In place of applying fire heat to the generator, as had been hitherto customary, a coil of steam pipes is employed for evaporating the ammoniacal vapour. The advantages derived from this are that the pressure and temperature in the generator can be much more easily regulated, and, moreover, the ammonia separates from the water better at a low heat, and an even temperature is found to be most essential to the efficient working of the apparatus. The steam-heated evaporat- ing pipes consist of a number of straight pipes connected together by bends, giving a very large heating surface, and when the exhaust steam from the engine is employed therein for heating purposes, a very great saving of fuel is effected. The analyser is placed upon the generator so as to economise space and save the connections otherwise necessary. The said analyser is formed preferably cylindrical, and is fitted with a series of dishes or trays haying passages so arranged that the 102 REFRIGERATING AND ICE-MAKING I^IACHINERY. vapour impinges on the undersides thereof, and traverses the vessel without passing through the liquid. Each of the dishes or trays is provided with an overflow pipe which is raised above the level of the bottom thereof, so as to keep some liquid in the said dish or plate, but always below the top of the vapour outlet. As the ammonia vapour is driven off from the solution of ammonia and water, by the heat of the vapour rising from the tray below, it passes through the vapour outlets into the rectifier without going through the liquor on the tray or trays above. By this means a considerable saving of fuel is effected, as the ammonia when once separated from the water on each tray or plate is at once delivered to the rectifier. Otherwise, were this not so, water has such a strong afiinity for ammonia, that the vapour which had been separated from the liquor on one plate would quickly become absorbed again by the liquor it had to pass through on the next plate. The rectifier is placed on the condenser, the two forming in fact one vessel, and the same condensing water does duty for both, the latter passing in at the bottom of the condenser where the coldest water is wanted, and up the outside ot the coil into the rectifier, from which it passes to the absorber. The ammoniacal gas or vapour passes from the analyser into the top of the coil in the rectifier, which coil is fitted at intervals with pockets to •carry off the water resulting from the condensation of the vapour coming from the analyser, so that immediately any such con- densation occurs the liquor passes at once out of the coil, and the ammoniacal vapour does not come in contact with the water after being separated from it. By providing the said pockets with cocks or valves suitable adjustments of the apparatus can be effected. The ammonia gas thus passes to the condenser in a prac- tically anhydrous condition, which is absolutely essential to the economical working of the apparatus, and which would not otherwise be the case, as if the said gas comes into contact with the water resulting from its condensation it would re-absorb a portion of it. The condenser coil is contained in a cast or wrought-iron cylinder, and to simplify the apparatus and to save space, the condenser is placed upon the receiver, the latter being a plain wrought or cast-iron vessel serving, as before, to store the anhydrous ammonia before it goes into the cooler or refrigerator; it is fitted with a glass gauge, or a float gauge to indicate the THE ABSORPtiON PROCESS. 1 63 level of the liquid therein. When the latter is employed, revolving spindles or rods working vertically through stuffing boxes in the usual way are preferably used, as tending to mini- mise friction and prevent leakage. The refrigerator or cooler is substantially similar to that employed in the former arrangements, but is fitted with a self- closing gauge in case of breakage. The absorber is constructed of smaller pipes or tubes, so as to enable a greater number to be used than heretofore, and thus for a given content to secure a very much larger surface exposed to the action of the cold water which surrounds the said tubes ; the latter are preferably constructed of wrought- iron. Another saving of condensing water is effected l)y having a few of the top pipes above the upper extremity of the water cistern, and letting the warm water coming from the rectifier ^rip over the outside of the said pipes. The heat due to the ammoniacal gas being absorbed by the weak Hquor, which is given off from the inside, is sufficient to vaporise a portion of the water, and a large quantity of heat becomes latent in the vapour, producing a refrigerating effect. The pump employed for drawing the strong solution of ammonia produced in the absorber, and forcing it through the coil of pipe in the heater into the analyser, against the pressure, is so constructed that there are the very least possible clearances, and that the whole or practically the whole contents are dis- charged at each stroke, thus preventing expansion of gas on the return stroke, tending to keep the suction valves closed. The pump cocks, valves and gauges are provided with water con- tainers, so that should any leakage of ammonia through the stuffing box occur, the water will absorb it, the latter being re- turned into the apparatus when it becomes thoroughly saturated. The stuffing box cock is constructed with a guard, and with an adjustable clamp screw, which holds the key to its seat, preventing leakage from compression of the packing, and ad- mitiing of the said stuffing box being repacked whilst the apparatus is at work. To allow for the gradual weakening ot the solution of ammonia, a small vessel or still is provided in connection with the generator, wherein the weak solution from the latter is evapo- rated off at a low temperature into the apparatus, where the least pressure exists. In the invention patented by William Henry Beck, in 1886, 104 REFRIGERATING AND ICE-MAKING MACHINERY. some still further improvements in various details of construc- tion are described, notably in the arrangement of the anal3ser and rectifier, and the absorber. In the first-mentioned vessel a series of sheet iron or steel trays with or without perforations, the edges whereof are drifted or set up so as to form short adjutages, are provided. Each alternate one of these trays has a central opening, and each intermediate tray an annular space left between its circum- ference and the enclosing case or cylinder. An inner sheet metal casing is, moreover, provided in which the water separa- ting trays are secured, and which, together with such trays, can be easily removed and replaced in position ; and the mouth of the vapour outlet pipe is sometimes surrounded by a finely perforated w^ire gauze chamber or guard. The absorber is formed with a primary absorbing vessel, wherein the absorption of the ammonia gas is effected to an extent dependent upon the temperature of the ordinary cooling or condensing water, combined with a secondary absorbing vessel wherein a further absorption of the ammonia gas is effected by the cooling action of a current of cold brine, or of water, cooled to a temperature below that of the ordinary cooling or condensing w^ater used in the primary absorber. The weak liquor cooler, the liquid ammonia receiver, the condenser, and the rectifier are contained in a single open-topped tank provided with divisions or partitions so arranged as to ensure the passage of the cooling orcondensingwatersuccessively through each of the compartments. Frederick Noel Mackay and Adolph Gothard Christiansen obtained a patent for improvements in ammonia absorption machines in 1887, the main features of which that are claimed as novel being as follows, viz. : — The separation of the ammoniacal gas from the liquor in which it is absorbed, by boiling the said liquor in stages within the same boiler. An analyser consisting of a chamber containing superimposed spirally corrugated plates having perforations or openings. The combination within one chamber, of an ammoniacal liquor boiler and analyser. A rectifier consisting of such an arrangement of a coil or coils, that the gas will take an upward direction, and the liquid a downward direction. A condenser wherein the coils are so connected that the gaseous ammonia passes from coil to coil in an upward direc- THE ABSORPTION PROCESS. 1 65 tion, whilst the Hquid ammonia flows in a downward direction. A multiple coil condenser so constructed that it has but one single through way. A rectifier and condenser consisting ot chambers containing coils, all the joints whereof are situated on the exterior. An auxiliary cooler composed of a chamber fitted with a coil and regulator, and suitable connections. A vaporiser and refrigerator wherein the brine flows through a chamber, whilst the liquid ammonia expands through small per- forations or apertures into tubes contained in the said chamber. An absorber constructed with a concentric corrugated chamber. Ammonia pumps provided with a chamber through which ammonia liquor from the absorber passes. An arrangement w hereby ammoniacal liquor from the absor- ber is caused to cool ammoniacal liquor from the boiler. " In Edward Henry Tompkins' patent, which was granted in the latter part of 1887, for improvements in refrigerating apparatus of the kind or class for which previous letters patent were granted to Rees Reece and William Henry Beck, the chief novel points claimed are : — The placing of the generator within the boiler so as to secure the full efficiency of the heat given off by the steam generated therein. The combination and connection with the main gas pipe from the generator, of a vessel doing the triple duty of heater, rectifier, and analyser ; which vessel consists of an iron tank with an arrangement of tubes, and a sealed joint or joints at the base through which the gas rises. An improved form of condenser, consisting ot an ordinary condenser of the multi-tubular pattern, wherein the tubes are passed through a tube plate and expanded in the usual manner, but having in addition horizontal partition plates of metal at the alternate ends of the tubes, whereby the ammonia is caused to travel backwards and forwards along the alternate layers or sets of tubes, and thereby to receive the full benefit of the cold of the condensing water. By the removal of the end covers, moreover, each layer or set of tubes is rendered readily acces- sible for cleaning or repairs. A cooler or refrigerator comprising a system of horizontal tubes placed in a large tank, within which latter a solution of chloride of calcium is caused to circulate so as to secure an I06 REFRIGERATING AND ICE-MAKING MACHINERY. equable temperature throughout the entire length of the tank. An absorber, wherein provision is made for intimately mixing the ammonia gas from the refrigerator or cooler, with ammonia liquor, cooled, firstly, by passing it through a small cooler, and secondly by bringing it in contact with a series of tubes through which water is made to circulate, thereby eftecting a consider- able gain in the working of the apparatus. An ammonia pump provided with a stuffing box wherein is inserted a hollow steel or iron ring of suitable dimensions, to which ring is connected a pipe leading to a receiver having a glass gauge to show the height or quantity of liquor ammonia which has escaped past the first series of packing, and is con- tained therein. From this receiver a pipe fitted with suitable stop-cocks or valves leads to a small hand-force pump or com- pressor of the ordinary type, so that by opening and closing the said stop-cocks the escaped liquor can be withdrawn into the pump or compressor, or forced back into the generator, as may be desired. The provision of means whereby the ammonia liquor from the absorber is passed through a coil contained in the compound vessel doing triple duty as heater, rectifier, and analyser, and consequently enters the generator at a high temperature, and the temperature of the ammonia gas on its way to the condenser is likewise reduced. The condensation from this ammonia gas which occurs in the rectifier and analyser, is conveyed back to the generator by gravitation ; the above-mentioned compound or triple vessel being situated above the level of the said generator, and the pressure in both vessels being, equal. A small cooler wherein the weak liquor ammonia coming from the generator in its heated condition, is reduced to a state of comparative c-oolness, by contact with tubes cooled by a circulation of cold water, to which water may be added, if required, waste ice to increase its cooling capacity. The advan- tage claimed for thus reducing the temperature of the weak ammonia solution, is that its power of absorbing the ammonia gas from the cooler or refrigerator is thereby greatly increased. The patent granted to Edmund Lionel Pontifex in 1887, subsequently to both those just mentioned, for improvements in cooling and refrigerating machines of the class described in the specification of former letters patent, granted to H. F. Stanley, in 1875, ^^ys claim to the following : — The method of mounting the condenser coils upon brackets THE ABSORPTION PROCESS. 107 projecting inwards from the side of the cistern, and retaining them in position by means of uprights extending vertically from these brackets; some of which uprights are extended above the tops of the condenser coils for the purpose of supporting the rectifier coil, and also for carrying a vertically arranged cylinder ■occupying a space in the centre of the rectifier coil, and extend- ing to above the level of the overflow from the cistern. The object of this cylinder is to ensure that the cooling water, that rises up through the cistern, should flow only through the annular space or clearance situated between the exterior surface of the said cylinder and the inner surface of the cistern, and thus cause it to act in a more efficient manner to cool the rectifier coil which is contained in this space or clearance. An arrangement for ensuring an uniform action taking place in all the concentric coils of the condenser, and causing the liquid coming therefrom to be of the same temperature, consist- ing in spacing the outer coils vertically further apart than the inner coils, so that the increased diameter of the outer coils is 'Compensated for by the greater number of the inner coils. To provide for the more perfect regulation of the admission ■of the anhydrous ammonia liquid to the cooler, which requires very fine or minute adjustment, a stop-cock is provided with a plug through which, in addition to the way or passage which is usually formed therein, there are, at the sides of this way or passage, other narrow passages which, when the said stop-cock is partially turned on, allow of a small and easily regulated quantity of Hquid or fluid being permitted to pass ; whilst, on the other hand, it likewise admits of a large volume of the said liquid being allowed to pass quickly, whenever the cock is turned full open, as is sometimes necessary for the purpose of clearing the small passages by blowing out any obstructions which may lodge therein and choke them. The insurance of a more effective absorption of the gas, by so arranging the absorber that the weak ammonia liquor or solution is made to fall in the form of a shower on to the sur- face of a tray, which latter is provided with small holes or per- forations arranged in concentric circles. Through these holes the said weak ammonia liquor percolates or drops down on to the tops of the coils of cooling pipes, trickling slowly from ■coil to coil until it reaches the bottom of the absorber, from which latter it is sucked by the ammonia pump through a pipe fitted at its inlet end or extremity with a perforated strainer or guard, in order to prevent the said ammonia pump suction pipe Io8 REFRIGERATING AND ICE-^IAKING jSIACHINERY. from becoming accidentally choked or stopped up by any foreign bodies. In order to enable the interior of any of the coils of pipe in the absorber being readily cleared of any deposit, suitable means are provided for admitting of a pump cylinder being easily attached to the outlet of each of the said coils. This cylinder is fitted with a piston which, by means of a piston rod extending therefrom, can be jerked or moved suddenly and violently to and fro, whilst the cooling water is flowing through the coil. The shock thus caused liberates any scale that may have become deposited inside the coil, and the said scale is carried off by the flow of the condensing or cooling water. An improved method of forming gas-tight joints, for use wherever the end of a coil or of a pipe is to be secured to the sides or ends of any of the vessels or chambers, is moreover set forth and claimed. A nut is screwed on to the pipe on either side of the plate, and on one or both sides of the said plate a circular recess is formed around the said pipe. Into this recess, and around the pipe, is inserted a packing ring or insertion of india-rubber or of any other suitable material, ^^hich ring is circular in transverse section. The nut screwing on the pipe is likewise shaped circular at one end so as to enable it to enter and fit into the said recess, or in some instances a washer, so formed, or dished or hollowed out, that when forced against the said packing ring it will cause it to press inwardly against the pipe, is interposed between the nut and the plate. In this manner a perfectly gas-tight joint, capa- ble of withstanding considerable pressure, is formed, the india- rubber or other packing ring or insertion being firmly held in position so that it cannot escape from the pressure that is put upon it. The Pontifex ammonia absorption machine has been further improved by Wood, and the Pontifex-Wood apparatus, as at present constructed, is probably as near to perfection as can be attained in machines of this class. Fig. 39 is a perspective view, showing in elevation the general arrangement of a machine of the Pontifex and Wood type, which comprises a generator, a separator, a condenser, a refrigerator, an absorber and an economiser, all of which are fitted with the latest improvements. Referring to Fig. 70, page 190, and Fig. 74, page 200, which views show two applications of the said machine, a is the generator, e is the separator, c is the condenser, d is the re- THE ABSORPTION PROCESS. 109 frigerator, e is the absorber, and g is the economiser. The ammonia pumps shown in Fig. 39 are of the original pattern employed; those illustrated in Figs. 70 and 74 are of the latest design, the construction of which will be more clearly under- stood from the enlarged views, Figs. 40 and 41. The generator a consists of an horizontal cast-iron cylindrical vessel, containing a coil of steam^pipe adapted to be heated by direct or live steam from the ordinary steam boilers, and into which the charge of commercial ammonia is inserted. The separator b, which is connected to the top of the generator by suitable flanges, and arranged vertically, and at right angles to the latter, is so constructed that any aqueous vapour that rises with the vaporised or gasified ammonia from the generator, will be arrested or trapped by a suitable arrange- ment of baffles or checks, and is returned into the said generator ; the practically anhydrous ammonia passing through a pipe from the top of the separator to the condenser d. In the condenser d, which consists of a number of coils of pipes enclosed in a wrought-iron vertical cylinder which is constantly kept full of cold water in circulation, the anhydrous ammoniacal gas or vapour is condensed and liquefied by the pressure caused by its own accumulation. The liquid ammonia, which leaves the condenser at a temperature of between 70° and 80° Fahr., next passes into no REFRIGERATING AND iCE-MAKING T^IACHINERY. the cooler or refrigerator e, which is a vertical cast-iron vessel fitted with coils of wrought-iron pipes, through which a circu- lation of water or brine is kept running. In this cooler or refrigerator the said liquid ammonia instantly expands, and again takes the form of gas or vapour. During this expansion its sensible heat becoming latent, as already stated, its tem- perature is reduced instantly to from io° to 20° Fahr., or considerably lower if required, and the water, or where employed for ice-making, the brine is reduced or cooled down to any predetermined temperature. After performing its cooling office in the refrigerator D the ammonia gas or vapour is led through another pipe into the absorber e, wherein it comes into contact with, and is taken up and absorbed by, the water from which it was first eliminated in the generator a, the strong solution thus formed being drawn off by the ammonia pumps f and forced back through the economiser or heater g (wlierein its temperature is raised by the water which is passing from the generator into the absorber) into the generator a to be re-evaporated. The improved ammonia pumps, which are of a patented design, are mounted in a frames, as shown in Fig. 70, and when employed with a brine circulation, a brine pump is also attached to the outside of one of the said a frames, and is driven by means of a disc crank fixed upon the shaft carrying the eccentrics for working the ammonia pumps. One of the ammonia pump cylinders is shown in side eleva- tion, and vertical central section, in the enlarged views Figs. 40 and 41. As will be clearly seen from the sectional view, Fig. 41, the pump is of the piston type and double-acting. A great advantage in having two ammonia pumps is that they can be so arranged, that, if necessary, one of them can be shut off for repairs or overhauling, whilst the other is con- tinued in work. The method of working the Pontifex-Wood improved ammonia absorption machine is as follows : — All connections being properly made, and the generator filled or charged, with the ordinary ammoniacal liquor of commerce, up to the proper level, as indicated by the gauge attached thereto, a little steam is admitted to the coil of pipes inside the said generator, so as to raise just suflicient pressure of gas or vapour to expel all the air from the apparatus through an escape valve provided for that purpose in the absorber. As soon as all the said air is thus expelled, the full pressure THE ABSORPTION PROCESS. Ill of st:am is turned on to the heating coils in the generator, and the ammonia in the solution, being extremely volatile, is instantly driven off in the form of gas or vapour, and passes up tlirough the separator, where any aqueous vapour is arrested/ and returned to the top of the condenser; the Fig. 40. Fig. 41, aqueous portion of the ammoniacal solution remaining behind in the generator. The condensing water is admitted at the bottom of the condenser and is taken off at the top, the ammoniacal gas or vapour taking the opposite course and passing downwards through the coil of pipe therein, the upper portion of which coil is provided at intervals with traps or pockets, and is known as the rectifier. During its passage through this coil the gas or vapour is reduced in temperature by the condensing water, 1 1.2 REFRIGERATING AND ICE-MAKING MACHINERY. and any watery particles that may have escaped the separator, and been carried over with the ammonia, are caught in the above mentioned traps or pockets, and are immediately passed out of the coil and returned to the said separator, through the connection shown in the drawing. After passing the lower- most trap or pocket the ammoniacal gas or vapour is quite dry or anhydrous, and it is the practically perfect reduction thereof to this condition that constitutes the chief advantage ot the Pontifex-Wood improved machine. The dry or anhydrous ammoniacal gas or vapour now continues to descend the coil in the condenser, until, by reason of its accumulation, it reaches a pressure at which it becomes liquefiable, the said liquefaction being greatly forwarded by the reduction of temperature effected in the said condenser by the constant circulation of the cooling water. The apparatus is so constructed and regulated, that, as the gas or vapour becomes liquefied, the product of liquid anhydrous ammonia passes into the refrigerator, wherein it vaporises at the ordinary atmospheric pressure, at a temperature as low as — 28° Fahr., and at the moment it thus changes its form it absorbs and renders latent a very large amount of heat, as has been already mentioned. The water or other liquid to be cooled is passed direct through the coil arranged in the refrigerator ; or, where ice- making is carried out, a strong solution of chloride of calcium or brine is passed through it, cooled to the requisite low temperature, and pumped into the ice-making or freezing tanks. The ammonia, which has now again assumed a gaseous form, passes from the top of the cooler or refrigerator into the absorber, which latter is connected to the bottom of the generator, through a suitable pipe, the pressure in the latter forcing a constant stream of the water left in it at starting into the absorber, where this weak solution greedily absorbs or takes up the gas coming from the refrigerator, and the strong solution thus formed, which is similar to that first placed in the generator^ is drawn off by the ammonia pumps. The strong rich solution is then forced through a coil of pipe in the economiser or heater into the top of the separator, wherein it passes down through a succession of trays, which latter are heated by the hot vapour or gas ascending from the generator and: he ammonia is once more separated from the water in which it is dissolved, the solution gradually becoming THE ABSORPTION PROCESS. II3 weaker^ until it finally falls back into the generator almost entirely exhausted of ammonia. As in Carre's apparatus the complete process forms, it will be seen, a continuous closed cycle, the changes from liquid to gas and vice versa being constantly repeated. Theoretically the only outlay for working the machine, out- side the small amount of oil required for lubricating the moving parts and the labour, is that entailed for the coal or other fuel consumed in raising steam for heating purposes, where exhaust or waste steam is not employed, and for supplying the small steam-engine requisite to drive the ammonia pumps j in cases, however, where water has to be paid for, there is an additional outlay for the water that is used for condensing and other pur- poses. The boiler power required, where direct or live steam is used, varies from 2 horse-power in the smaller machines, which are capable of performing work equal to the reduction of 225 gallons of water 10°, or of 60,000 cubic ft. of air 20° Fahr. per hour, or of an ice equivalent melted per 24 hours of i\ tons ; up to 15 horse-power in the larger sizes adapted to so treat 8,000 gallons of water, or 1,900,000 cubic ft. of air, or of an ice equivalent in tons melted per 24 hours of 50 tons. In like manner the indicated horse-power that is necessary for driving the ammonia pumps will run from one, in the small machines, up to six in the larger sizes ; and the amount of con- densing water at 50° Fahr. from 100 to 3,000 gallons per hour. In practice a certain amount of the ammonia is always un- avoidably lost by leakage, even under the most favourable cir- cumstances. The amount of ammonia that thus goes to waste and has to be replaced depends chiefly upon the care taken in packing the ammonia pumps, but under average conditions it usually varies from 240 to 400 lbs. per annum. The price of the ordinary commercial liquor ammonia used in the machine is from 3d. to 4d. per lb. In some exceptional cases, however, machines have run in a satisfactory manner for two or three years without any additions of ammonia having been made. Other refrigerating machines acting on the above principle, of which mention may be made, are those of Hill, Seeley, and another one of French origin. A number of British patents have been obtained by Fredenck Barker Hill, both singly and in combination with others, for improvements in ice-making and refrigerating machinery. No. 3427 of 1876, Nishigawa and Hill ; No. 6808 of 1885, ^i^^ I Il2,a REFRIGERATING AND ICE-MAKING MACHINERY. and Gorman; and No. 15914 of 1886, Hill and Gorman, con- tain certain improvements in absorption machines, the latter patent comprising mainly improved means for heating the ammonia boiler and for the formation of cold stores for refrigerating purposes. Hill, No. 13487 of 1887, describes a refrigerating machine with mercurial jjump, wherein mercury is employed for drawing a4r or other gas or vapour into and discharging it from one or more chambers. It is stated that the mercury acts as a seal to close the aperture of the suction pipe, and that, consequently, the use of a suction valve can be dispensed with. This pump may be adapted for use with an apparatus such as described in the previously mentioned patent. No. 17071 of 1888, Hill and Sinclair, contains a description of a refrigerator or ice-making machine mounted upon road or travelling wheels, and provided with suitable means whereby motion may be transmitted to its driving-shaft from one of the said wheels during transport. No. 2081 1 of 1889, Hill and Sinclair, contains certain im- provements in the absorption machine described in No. 15914 of 1886. The ammonia boiler or still is formed in this case of two horizontal tubes connected by suitable pipes which extend longitudinally within the said tubes. The horizontal parts of the said pipes are perforated at their upper sides to ensure uniformity in the action of the apparatus. In combination with the refrigerating apparatus are employed two slabs or tables formed of metal or other suitable material of good thermal conductivity, beneath which circulates brine or other non-con gealable liquid for conveying the cold from the refri- gerating tubes or chambers to the slabs or tables. These cold slabs or tables are adapted for facilitating and expediting the manufacture of chocolate, confectionery, pastry, and other substances which are formed in moulds, and which can be manipulated upon the said slabs or tables. Hill, No. 16253 of 1889, describes an improved refrigerating and ice-making machine, adapted to work on the intermittent ammonia-absorption process. The main features of the invention consist in the production of cold by this method, wherein impoverished ammoniacal liquor from the ammonia boiler is caused to pass into one or more supplementary or auxiliary absorbers, in which the ammoniacal gas is subse- quently absorbed, and from which the said liquor together with THE ABSORPTION PROCESS. II3<5 trie gas absorbed thereby is then returned to the ammonia boiler. In ammonia-absorption refrigerating and ice-making machines as constructed before the date of this invention, it was necessary, after the distillation of the ammonia, to reduce the temperature of the liquid in the boiler until the pressure became sufficiently diminished to permit the vaporization of the liquid ammonia in the refrigerator, and until the liquid in the boiler was suffi- ciently cool to permit the absorption of the ammoniacal gas thereby. This cooling of the said liquid necessarily occupied a considerable space of time. Besides, in many of these refrigerating and ice-making machines the absorption of the ammoniacal gas took place only at the surface of the liquid in the boiler, and was necessarily a slow process, the hquid being of higher temperature at the surface than at any other part thereof, and having its temperature raised at the surface by the condensation of the gas. - The inventor claims to have discovered that, by employing one or more separate or auxiliary absorbers, which can be put in communication with the boiler, the cooler or condenser, and the refrigerator as required, and in which the ammoniacal gas can ascend through a body of liquid, he can very rapidly diminish the pressure in the ammonia boiler by absorbing the gas from the boiler, the rectifier, and the condenser in the absorber or absorbers ; and is enabled to effect the absorption of the ammoniacal gas from the refrigerator, either in the sup- plementary or auxiliary absorber or absorbers or in the boiler, immediately or very soon after the distillation, thus greatly expediting the production of cold by the machine. Fig. 4i« is a front view partly in section, and Fig. 41^ is an end view of Hill's refrigerating apparatus provided with a sup- plementary or auxiliary absorber. A indicates the ammonia boiler, b the separator or rectifier, c the cooler or condenser, and d the refrigerator, e is the supplementary or auxiliary absorber, which is connected with the boiler a, the condenser c, and the refrigerator d by pipes F, F^, F^ F^, fitted with stop-cocks or valves G, g\ g^, g^ By the manipulation of these cocks as may be required, the im- poverished ammoniacal liquor from the boiler may be intro- duced into the absorber e after the distillation of the ammonia, and the liquid chaiged with gas by absorption may be caused to return from the absorber to the boiler. Thus when the 113^ REFRIGERATING AND ICE-MAKING MACHINERY. liquid anhydrous ammonia has been collected in the refrigerator D, the cocks G", g^^ are closed and the cocks g, g^ partly opened, so as to admit of the weak or impoverished solution from the boiler a, or a sufficient portion of it, being forced into the absorber e ; the cock or valve g^ is then closed, and the cock G" is opened to rapidly relieve the pressure in the condenser, rectifier, and boiler, by allowing the gas therefrom to become absorbed by the weak solution in the absorber e. As soon as the solution in the boiler is sufficiently cooled to permit re- Fig. 41a. Fig. 41^. absorption of the gas thereby, the boiler is placed in communi- cation with the refrigerator by opening the cocks or valves g', G^. The ammonia solution from the absorber e will be returned by gravity or in any other convenient manner into the ammonia boiler a, through the cocks g, g\ when required. Instead of placing the refrigerator d in communication with the boiler a, it may be so connected with the supplementary or auxihary absorber e, thereby permitting the vaporization of liquid ammonia in the refrigerator, and the absorption of the THE ABSORPTION PROCESS. 113^ ammoniacal gas by impoverished ammoniacal liquor previously introduced into the said absorber e from the ammonia boiler. While the vaporization of the ammonia in the refrigerator is thus proceeding, the weak solution in the ammonia boiler may be cooled, after which the refrigerator may be put mto com- munication with the said boiler. In Fig. 41c is illustrated the combination of an ice-makin^ apparatus, comprising a refrigerator d\ with an apparatus con""- structed as above-mentioned for cooling a room br chamber Fig. 4ir. and vvi h one or more supplementary or auxiliary absorbers e, E^. 1 he auxiliary absorber e^ is connected with the refrigerator D and with the cooling apparatus by pipes F^ f^ provided with stop-cocks or valves G^ c/, so that the absorber e, e^ can be used separately or simultaneously, either with the cooling apparatus or with the ice-making apparatus. "" Fig. 41^ illustrates another arrangement wherein a single auxiliary absorber e is used in combination with a cooling apparatus and an_ ice-making apparatus, or with two or more sets ot cooling or ice-making apparatus. 113^ REFRIGERATING AND ICE-MAKING MACHINERY. By the above arrangements the cooh'ng of rooms or chambers and the making of ice can be very effectually performed either separately or simultaneously. If desired, suitable provision may be made for effecting the return of the liquor from the absorber or absorbers to the boiler by the pressure from the refrigerator or in any other convenient manner. In Fig. 41^ is shown an entire cold storage apparatus having the said inventor's present improvements applied thereto, l is Fig. 41^. a coil boiler for heating the solution in the ammonia boiler a, with which the said coil boiler is connected through the medium of a separator m. n is the room or chamber to be cooled. In the upper part of this chamber is arranged a tank h contaimng the non-congealable liquid in which the refrigerator tubes d are immersed. The bottom of this tank is made with corrugations or V-shaped portions H-, and gutters or channels k are arranged beneath the V-shaped portions for the purpose of collecting any dripping therefrom THE ABSORPTION PROCESS. "3/ Iji Seeley's absorption machine anhydrous ammonia is also the agent or medium employed. The novel feature in his apparatus is the arrangement of the generators, which can be alternately heated by means of steam coils, and which are charged with dry 114 REFRIGERATING AND ICE-MAKIXG MACHINERY. pulverised chloride of calcium. On heat being applied to one of the said generators the liberated gas rises, is passed through a condenser, expanded and evaporated in a refrigerator, and lastly returned to the second generator, wherein it is taken up or absorbed by the dry chloride of calcium. Heat is then applied in its turn to the said second generator, and the operation is reversed, and so on ad i?tji?iitiwi, the said generators alternately becoming absorbers. In the French machine the refrigerating agent used is amylic ether, which is capable of dissolution under the action of sulphuric acid. The ether is first extracted from the acid under the action of heat, is liquefied under a considerable pressure, and is passed into a suitable receiver or container, from which it can be admitted by means of a stop-cock or valve to spiral ducts surrounding a cylinder or vessel containing the water to be frozen, wherein by its expansion into gas it abstracts the heat, as already mentioned with respect to other machines of this class. The vapour is then returned to a vessel containing sulphuric acid, by which it is once more absorbed, to be sub- sequently again expelled or driven off therefrom by heat, and to pass through the same cycle of operations as before. Those machines wherein a refrigerating agent is used, which consists of a compound or dual liquid, one of which is capable of liquefaction at a comparative low pressure, taking the other or second one into solution by absorption ; or, in which the refrigerating agent is liquefied partly by absorption and partly by mechanical compression, are said to work on what is usually known as the binary or dual absorption system. Johnson and Whitelaw's machine is designed for use with bisulphide of carbon. This refrigerating agent is first vaporised, and with the air introduced by the force-pump is passed through chambers charged with oil, by which the bulk of the moisture of the gas is taken up or absorbed, provision being made for extracting that of the air by passing it through a pipe leading to the air-pump, which pipe is partially filled with chloride o^ calcium. Pictet's refrigerating agent consists in a combination of carbon dioxide and sulphur dioxide, which forms a liquid having a vapour tension much less than that of carbon dioxide, or even of sulphur dioxide, at temperatures above 78° Fahr. An un- proved cooler or refrigerator patented by Pictet in 1887, which can be employed either with a compression or an absorption machine, has been already briefly described on page 68. THE ABSORPTION PROCESS. 115 In Nicolli and Mort's machine the refrigerating agent used is ammonia. The apparatus consists essentially in three main parts, viz., an evaporator, a pump, and an absorber, and the operation is as follows : — The evaporator or generator is first charged with strong ammoniacal liquor, vaporisation being effected by reducing the pressure through the action of the pump, and heat being abstracted thereby from the liquor to be cooled in the usual manner; the evaporator or generator thus performs a dual office inasmuch as it also acts as the refrigerator. The weak or exhausted hquor passes out at the bottom of the evaporator and is conducted through suitable pipes to the pump, where it meets the ammonia gas or vapour, and, together with the latter, is pumped into coolers, sufficient pressure being applied to liquefy the vapour, and cause a re-dissolution thereof; the strong solution is then returned to the evaporator, passing o» its way through an interchanger wherein its temperature is ^reduced by that of the cold, exhausted, or w^ak liquor also passing there through to the pump. De Motay and Rossi use as a refrigerating agent a mixture of common ether and sulphur dioxide or sulphurous acid (SO2), which compound is known as ethylo-sulphurous dioxide. It was found by experiments that, at ordinary temperatures, liquid ether has the power of taking up or absorbing large volumes of sulphur dioxide, amounting to as much as three hundred times its own bulk, the tension of the vapour given off from the dual liquid being below that of the atmosphere at a temperature of 60° Fahr. The two liquids are evaporated in the refrigerator by reducing the pressure through the action of the air-pumps. The pressure in the condenser is at no time in excess of that required to cause a liquefaction of the ether. The capacity of the pump need not be so large as that which would be necessary were ether employed by itself, but it is necessarily somewhat more than that demanded for pure sulphur dioxide. De Motay and Rossi's apparatus is said to have given very good results in the United States, where it has been in use for the past twelve years. CHAPTER VIII. The Abstraction of Heat by first Co:mpressing Air or other Gas, cooling same, and after- wards permitting it to expand, that is first applying heat in order ultimately to pro- duce cold, o]^ the cold-air system. Machines construcied on ihis sysiem opeiate on a principle which is one of the simplest in physics, viz., that the compres- sion of air or other gas generates heat, and the subsequent expansion thereof cold. Mechanical work and heat being respectively convertible, it follows that should a gas be caused to perform certain work on a piston during expansion, its store of caloric will be exhausted thereby to a degree equal to the thermal equivalent of the work done, the gas after expansion being at a lower temperature than it was before expansion, that is, provided always no heat is supplied from any other source to restore that so lost. Machines of this kind or class, although used from time to time for cooling hydrocarbons of a volatile nature, are more generally employed with ordinary atmospheric air only, hence they are commonly known as cold-air machines. Their inven- tion is ascribed to Gorrie, who is said to have designed the fi;st machine of this class in 1849. In Gorrie's machine the cooling water was injected into the compression cylinder, and brine to be refrigerated or cooled into a jacket surrounding an expansion cylinder. His apparatus consisted essentially of a double-action pump or compressor, a cooler connected with a compressed air vessel or reservoir, and a jacketed auxiliary pump. The opera- tion of the machine was as follows : Water was injected into the compressor cylinder at each stroke, on the side of the piston on which condensation or coni|)ression was taking place. The compressed air was then led through a worm or coil in the (J J o t/^^-' THE COLD-AIR SYSTEM. II7 cooler to the compressed air vessel or reservoir, from whence it was admitted to the auxiliary pump, which latter was driven by the expansion thereof. Through the jacket surrounding this auxiliary pump a circulation of brine or other non-congeal- able fluid was maintained, which brine was cooled by the expansion of the air in the pump cylinder, and which in turn reduced the temperature of an ice-making tank situated above the latter to the requisite degree. Imperfect cooling of the air after compression, combined ^with the damp condition of the said air, caused the failure of yj'^this machine to act in a satisfactory manner. \^jjJ^ The next advance was made by Dr. Alexander Kirk in 1863. ^ ^A^'' ve Dr. Kirk's machine had three cylinders, viz. one for compress- ^^^c?^^ ing the air, and two for the expansion thereof, all three of which had reciprocating motion imparted to their pistons by a single crank. One of the expansion cylinders was connected to each end of the compressor, thus actually forming two distinct systems. The pistons of the expansion cylinders were hollow and were perforated by a number of small holes, and fitted in- ternally with filters consisting of several layers of very fine wire gauze, the reciprocating action of the said pistons alternately causing air to pass through these perforations and filters, and drawing back the said air. The operation of the machine was as follows : — The air was compressed between the piston of the compressor, during its stroke in one direction, and one of the expansion cylinder pistons, the heat of compression being carried off by a suitable water jacket provided round the said expansion cylinder. On the descent of the expansion piston, the air passed through the perforations, parting with some more of its heat whilst traversing the sheets or layers of wire gauze, and finally expanding in the upper portion of the said cylinder, and performing work upon the descending piston. The cold air was caused to abstract heat from brine which circulated round the top cover of the expansion cyhnder, and through a number of hollow corruga- tions. The operation of the second or other expansion cylinder which was connected to the opposite end of the compression cylinder was, of course, identical. This machine \ysls worked up to a pressure of 200 lbs. per square inch, and a temperature of — 39° Fahr. was obtained. In 1869 a cold-air machine adapted to compress air in stages was invented by Marchant. In his apparatus the air passed first into one cylinder wherein it was compressed, and was then I I 8 REFRIGERATING AND ICE-MAKING MACHINERY. exhausted into another cylinder of smaller dimensions in which it was still further compressed. Giffard's first (1873) machine was so arranged that the air was mingled in the compression cylinder with sprayed v/ater, which became vaporised by the heat of compression, and ren- dered the said heat latent. The discharge valve from the expansion cylinder was situated in the piston, and was so adjusted that it would open automatically upon the pressure in the cylinder falling below a predetermined point, the air then passing through to the other side of the piston, and after- wards to the refrigerator. In the same year (1873) Postle designed a machine which was practically a modification of Kirk's cold-air machine. As in the latter the compression cylinder was connected at each end to an expansion cyhnder, but the pistons of the expansion cylinders, which were each composed of an upper part of smaller diameter and a lower part of larger diameter, were so arranged, that when the compressor piston started upon its stroke in either direction, the valve connected with that end of the compressor was forced upon its inner seat, and the air pressure moved that particular expansion piston to the inner end of its cylinder, the said valve being opened outwardly, however, before the end of its stroke by its projecting spindle striking against the inner cylinder end, and the latter part of the compression taking place in a small space cooled by a water jacket, and wherein the heat of compression was carried off. Upon the reverse stroke of the piston the said valve was raised against its outer seat by the current of air passing through the circumscribed passage around it, and a partial vacuum having been formed above the small portion of the expansion piston, the latter was moved outwardly by the unbalanced pressure in the expansion cylinder, the cooled compressed air passing through the piston to the inner portion of the cylinder. Similarly, however, to on the inward, the valve was opened before the end of the outward stroke of the piston by the other extremity of its spindle coming in contact with the top of the cylinder, but this time outwardly, and the air in the said inner portion thus expanded, and at the same time performed work on the compressor piston. The air reduced in temperature during expansion cooled brine circulating through a jacket which also formed the inner cylinder head of both expansion cylinders, the latter being placed end to end. The great improvement in this machine was that the bulk of THE COLD-AIR SYSTEM. II9 the compression was performed during the period wherein the compressor was in connection with the water-cooled spaces, and most of the expansion whilst the said compressor was exhausting from the spaces in contact with the brine circulation, A very decided advance was next made by Windhausen, for whose improved cold-air machine a German patent was granted about this time. The characteristic feature of his apparatus, was the improved method by which the air, that had become heated by compression, was first cooled in a series of condensers or coolers by means of a circulation of cold water, and was then passed into a chamber where expansion or dilation took place behind a piston. That is to say, in point of fact expan- sion was effected by the simultaneous action of the machine before the said air was utilised for refrigerating purposes. The original Windhausen cold-air apparatus is shown in plan and side elevation in Figs. 42 and 43, by which the principle of the machine is sufficiently clearly illustrated to render an extended description thereof unnecessary. On the drawing, a indicates the compression cylinder, b the expansion cylinder, c the steam engine or other motor for operating the machine, and D, D^, D-, the condensers or coolers through which a constant current of cold water is maintained for cooling purposes. The cylinders A and B are arranged tandem fashion, and are worked simultaneously from the engine crank-shaft e, through the crank e^, and connecting rod f. The air enters the compression cylinder a through the inlet A^, as indicated by the arrows, and after compression the cur- rent passes through the pipe a^ to the first condenser or cooler D, from which it is conducted successively to the coolers d^, d^, and from the latter to the expansion cylinder b, as shown by the arrows. Within the coolers or condensers d, d\ d^, are arranged a series of pipes through which the blast passes, and around which a constant circulation of cold water is kept up, the litter entering the cooler d^ at a suitable inlet, and flowing through the said coolers in the opposite direction to the compressed air. A portion of the heat that has been imparted by compression is thus extracted, and the compressed air, which is at a temperature only a few degrees above that of its natural state, is led into the expansion cylinder b, wherein the expansion is effected i nder a gradually decreasing pressure, which latter is automatically regulated by valves operated by the simple expansive force of the compressed air itself. I20 REFRIGERATING AND ICE-MAICING MACHINERY. Were the air to be dilated to its normal volume it is clear that an amount of heat equal to that which has been abstracted or taken up by the cold water in the coolers would be required ; as this, however, can be only partially returned by the small volume of air within the expansion cylinder^ a low degree of tempera- THE COLD- AIR SYSTEM. 121 ture is immediately obtained, which is more and more reduced with each stroke of the compressor, as the original air in the expansion cylin- der is replaced by the cooled com- pressed air. From the com- pression cylinder B the air is conducted to the space to be cooled, escaping with a velocity suffi- cient to admit of the current being con- ducted for 300 ft. through a channel 2 ft. in diameter, the temperature at the orifice of the latter being from — 30° to —35° Fahr, , or from 62° to 67° of frost. It has not been found advisable however, in prac- tice, to employ a conduit of this ex- cessive length. In the apparatus shown the dimen- sions of the com- pression cylinder are such that at each stroke of the piston 35 cubic ft. of air, and at every com- plete revolution of the engine, 70 cubic ft. of air are com- pressed, being reduced to the extent of from two and a half volumes to one volume, or to a pressure of 35 lbs. per square 122 REFRIGERATING AND ICE-MAKING MACHINERY. inch ; thus, at a speed of 36 revolutions per minute, over 150,000 ft. of cubic air will be compressed per hour. t'rora actual experiments it was found that \^ith the air entering the compression cylinder at a temperature of 80° Fahr., it rose after compression to 205°, thus giving a gain of 125°, inasmuch as this acquired heat is subsequently got rid of in the condensers or coolers -and expansion cylinder ; and an atmosphere is thus obtained which, whilst under a tension of two and a-half atmospheres, is almost at the same temperature as the air previous to treatment, the expansive force, and efifect, of a volume two and a-half ti:nes larger, being at the same time retained. Fig. 44. Fig. 44 is a vertical central section illustrating a modified arrangement of Windhausen's cold -air machine, wherein a single cylinder is used for compression and expansion, the air being condensed or compressed at one side of the piston, and expanded on the other. Two coolers are provided, situated in the bed of the machine, one of which is cooled by a circula- tion of cold water, and the other by the expansion of the compressed air. The refrigerator is situated above the com- pressing and expansion cylinder, and receives the expanding air from the expansion side of the cylinder thraiigli a tempera- ture regulator. In the drawing a is the compression side of the cylinder, and B is the expansion side thereof; c is the piston, which is formed hollow and filled with non-conducting material c' ; d is the cooler, through which a circulation of cold water is kept con- stantly flowing, and wliich is connected to the compression THE COLD-AIR SYSTEM. I 23 side A of the cylinder through the pipe or tube D^ and valve D-, and E is the second cooler, which is connected to the first cooler D and to which a certain amount of the expanding compressed air from the expansion side of the pump is admitted for cooling purposes. The tubes in both the coolers D and E, through which the compressed air passes from the compression side a of the cylinder, communicate through the pipe or tube e^ and valve e- with the expansion side b thereof. F is the ice-making tank or refrigerator, and G, G, are the ice- cans or cases. The ice-making tank f consists of a double- cased rectangular wooden box or vessel, the spaces between the outer and inner cases of which are filled or packed with loose cotton, or other suitable non-conductor of heat. The cover, which is formed of a single thickness of wood, is pierced with holes in which are fixed metallic cases or pockets for receiving the ice-cans G. f\ f^, are zig-zag partitions arranged between the rows of ice-cans so as to cause the air to come ^uUy into contact with the metallic cases or pockets supporting them. H is an india-rubber bag, which acts to maintain an uniform pressure within the ice-making tank or refrigerator f, by admitting or giving out air in accordance as to whether the pressure happens to be above or below that of the atmosphere. I is a valve which is open during the entire compressing stroke of the piston c, and which communicates through a suitable pipe or tube with the temperature regulator, from which a portion of the expanding air passes to the ice-making tank or refrigerator through a tube communicating therewith through the aperture F-, the remainder being delivered through another pipe or tube to the space round the compressed air tubes in the cooler e, through the aperture or orifice e^, with which latter space the ice-making tank or refrigerator is hkewise con- nected through a suitable pipe or tube, and the apertures f", e*. The temperature regulator and pipes or connections are situated at the rear of the apparatus, and are not shov/n in the drawing. -The compression side a of the cylinder is also connected with, and derives its supply of air from, the expanded air space in the cooler e through a suitable pipe opening into the latter at e^, and communicating with the former through the valve K. The operation of the apparatus is as follows, that is to say : The piston c, during its forward or compression stroke, com- presses the air contained in the compression side a of the pump cylinder, and under the pressure of the said air the valve 124 REFRIGERATING AND ICE-MAKING MACHINERY. d'* opens, and the latter passes through the pipe or tube d^ to the water-cooled tubes of the first cooler d, from which it then passes to the air-cooled tubes of the second cooler e. The cool compressed air next flows into the pipe or tube E^ and is admitted through the valve e^ to the expansion side B of the pump cylinder during a portion of the stroke, when the said valve e"^ is closed, and the air expands in the said chamber B during the remainder of the stroke. The cooled and ex- panded air flows out of the expansion chamber b through the valve I, during the entire return or back stroke of the piston c, to the temperature regulator, from whence a portion of it passes to the ice-making tank or refrigerator f, and the remain- der to the space round the compressed air tubes in the second cooler E. On the said return or back-stroke of the piston c, the air in the space round the tubes in the second cooler e is drawn or sucked into the compression chamber a thr ugh the inlet valve k. The improvements introduced into cold-air machines in 1877 by Eell-Coleman added very considerably to their prac- tical value. This invention comprised suitable means for cooling the air both in, and as it left the compressor, by sjDray or jets of water, and also for drying it again before it was passed into the expansion cylinder. The latter object was effected by causing it to flow through a set of coils, or pipes, situated in the chamber cooled by the machine ; or by providing for exposing these pipes to a current of the used or spent air passing out from the said chamber. On leaving the compressor the moist air was first passed through a chamber with perforated diaphragms, and was then conducted to the expansion cylinder through coils or pipes which had a very extended surface, and were cooled on the exterior to a lower temperature than that of the cooling water, thus still further reducing the temperature of the air, and inducing a deposition of moisture. A great objection to this system of cooling by internal injec- tion is the loss occasioned by the saturated condition in which the air, even when employed continuously over and over again, is constantly delivered to the machine. In 1877 Gifi"ard also greatly improved his (1873) machine, and brought it to the form shown in Fig. 45. In the drawing (which illustrates the apparatus in side elevation, some of the parts being shown in vertical central section) a indicates the compression cylinder and b the expansion cylinder, which are THE COLD-AIR SYSTEM. 25 both of the single-actmg type, and open at their upper ends ; c IS the condenser or cooler. The inlet and outlet valves to the expansion cylinder b, as also the inlet valve to the com- pression cylinder, which, as shown in the drawing, are situated in 126 REFRIGERATING AND ICE-MAKING MACHINERY. the lower ends to the said cylinders, are actuated through cams upon the shaft of the machine. The outlet valve from the compression cylinder a governs the delivery of the compressed air to the lower end of the condenser or cooler c, wherein, after passing through top and bottom chambers or spaces, and a central series or set of vertical water-cooled tubes, it is delivered through a suitable pipe to the inlet valve of the expansion cylinder, from which latter, after doing work upon the expansion piston, during its upward stroke, it is discharged during its return or downward stroke through the outlet valve (shown on the right-hand side) and led away through a suitable pipe to perform its cooling office wdiere desired. The compres- sion cylinder a is jacketed, and the heat generated during com- pression removed as far as possible by a circulation of cold water. In operation the air which enters the compression cylinder A through the inlet valve (shown on the right-hand side) is first compressed up to the normal pressure existing in the condenser or cooler c, when the outlet valve lifts and admits of its being passed into the latter, wherein it is cooled and dried by contact with the water-cooled tubes. The valve regulating the admission of compressed air to the expansion cylinder b is so arranged that itwill admit to the latter an amount of air equal to that which is being forced into the condenser or cooler c during the downward or compression stroke of the compressor piston, thus tending to maintain an equality ot pressure in the said condenser. The pistons are thus con- stantly moving in opposite directions, that of the expansion cylinder being, however, a quarter stroke in advance of that of the compressor. During the upward stroke of the expansion pis- ton, the inlet valve from the condenser or cooler c (shown on the left-hand side) remains closed, the expanding air performing a portion of the work of driving the machine ; whilst on the doAMi stroke the outlet or exhaust valve (shown on the right-hand side) opens, so as to admit of the cooled air passing through the discharge pipe, by which it is led away, as above mentioned, to perform its coohng or refrigerating ofhce where required. A form of cold-air machine was designed by Hargreaves and Inglis in 1878, wherein they dispensed with the use of separate compression and expansion cylinders, employing instead a single cylinder having two pistons connected by means of a trunk. The inlet and outlet valves, which w^re of the Corliss pattern, were arranged to be operated through suitable eccen- trics on the main shaft of the macliine. THE COLD-AIR SYSTEM; ^27 128 REFRIGERATING AND ICE-MAKING MACHINERY. In Tuttle and Lugo's machine the air is forced after com- pression through a set or series of tubes in a cylindrical or tubular chamber or vessel, which is cooled by a constant circu- lation of cold water, and through a similar set of tubes in a chamber or vessel, wherein the latter are surrounded by a volatile Hquid. After leaving this second vessel it is allowed to expand into the refrigerator or ice-making tank, rising through some such volatile Hquid as ether or bisulphide of carbon, which is placed in the bottom of the latter, and the said air and the vapour from the volatile liquid fill the interior of the refrigerating chamber surrounding the ice-cans or cases, and freeze or congeal the water therein. A bye-pass is also provided through which the compressed air can be conducted direct to the ice-making tank or refrigerator. Lugo and McPherson's apparatus comprises a blower, the air from which is forced through a cooler consisting of a chamber filled with some suitable porous material kept saturated with water. The cooled air is then passed into a compressor, the upper part of which is kept full of water, which serves to keep it cool and also to prevent leakage of the said air past the piston. From the compressor the air is led to a cooler, and from this to a compressed air reservoir or vessel, from which latter it is in turn admitted to, and allowed to expand in, the interior of a large ice-making tank or chamber, having non-conducting walls and rails for cars carrying the ice-cans or cases. The piston of the compressor is worked by La Hire's epicycloidal device. In i8So, Haslarn (Sir Alfred Seale Haslam) brought out a cold-air machine of the type usually known as dry air refri- gerators, which comprises certain very important improvements on the Bell- Coleman type of machine, which have had the effect of rendering it one of, if not the most successful machines of this class hitherto designed. Figs. 46, 47, and 48 are perspective views illustrating three different cold-air machines of the Haslam type. That shown in Fig. 46 is of the horizontal pattern, and is made in sizes adapted to deliver from 20,000 to 30,000 ft. of air per hour. Compound duplicated horizontal machines of heavier build are, however, also constructed, in sizes adapted to deliver from 35,000 to 300,000 ft. of air per hour. The apparatus is driven by a compound condensing engine, and this, together with the air-compressing and expansion cylinders, and the requisite water-pumps, are all mounted upon a cast- THE COLD-AIR SYSTEM. 129 f bo 130 REFRIGERATING AND ICE-INIAKING ^lACHINERY. v»S-^S5^7-^=:ir-— Fig. 48. iron bed frame, of box section, cored out to receive the air- cooler, engine, surface condenser, and air-pump. This com- THE COLD-AIR SYSTEM. I3I bination of the condenser casing with the refrigerator forms a foundation for the bed-plate of the steam-engine. The feed pumps are bolted on to the side of the bed, and are driven from an overhead rocking shaft, which likewise works the air* pump. Variable cut-off gear is fitted to both the steam cylin- der and the air-expansion cylinder, and the pistons of both the compressor and expansion cylinders are directly coupled to tail rods from the steam cylinder pistons. By locating the inlet and outlet valves in the cylinder-covers they are rendered very easy to get at for repairs and other purposes. The height of this machine is such as to admit of its being conveniently placed " between decks " of steamers. The patent diagonal pattern machine (Fig. 47) is made of smaller sizes, viz., to deliver from 10,000 to 12,000 cubic ft. of air per hour, and where a machine of still smaller capacity is required, one of the vertical pattern, such as that shown in Fig. 48, is preferably used, the latter machines being con- -^tructed of sizes to deliver from 2,000 to 6,000 cubic ft. per hour. In the diagonal pattern machine the compound high and low pressure steam cylinders, and the air compressor cylinder, are placed on the top of the bed, the air expansion cylinder is located at the end, and the water, air, and feed pumps are bolted to the side thereof. The bed is, as will be seen from the illustration, of massive box section, and is suitably cored out to receive the water- cooler tubes, the condenser tubes, and the patent drying pipes, and it likewise supports the main crank shaft bearings. The condenser tubes are fixed in position by means of screwed ferrules, and the air cooler tubes and drying pipes are secured in tube plates by expanding the ends in the usual manner. The several tube plates are provided with covers having ribs arranged for the proper circulation of air and water. As will be seen, the machine is peculiarly compact and self- contained, and the air-pump is arranged vertically, and is worked through a T bob from an eccentric on the crank shaft. The type of machine illustrated in Fig. 48 occupies but little floor-space, and its height allows of its location "between" decks of small steamers and yachts. The steam cylinder, air- compression cylinder, and expansion cylinder, are mounted vertically upon cast-iron standards, which latter are securely bolted to a cast-iron bed of hollow box section, supporting the crank-shaft bearings and containirg the air cooler, and the 132 REFRIGERATING AND ICE-MAKING MACHINERY. water-pump is bolted to the base-plate and worked vertically from a crossbead-pin. The crank-shaft, valve-rods, and connecting-rods, are of mild forged steel, and the slides are of the open type, and easily accessible. A portion of one of the cast-iron standards is made loose so as to admit of the crank being readily removed when desired. The above machines all have double-acting cylinders. The compressors are either of the water injection type, or of the dry type and water jacketed, discharging into the surface coolers in the beds. When a compressor of the first, or water injection type is employed, the above-mentioned cooler is dispensed witii, and a separate water tower is provided. After being cooled in the ordinary way by water, the temperature of the com- pressed air is still further reduced by passing it through an interchanger, wherein it is subjected to the cooling action of either the spent cold air leaving the enclosed space or chamber where it has been used for cooling purposes, or else of the cold air as it passes out of the expansion cylinder. In the first instance separate boxes containing the drying pipes are pro- vided inside the said cold chamber, in the second case the device is fitted in the forepart of the bed of the machine; the advantage derived from both these arrangements is that a further condensation and deposition of moisture are thereby effected. The exhaust valves of the expansion cylinder are separate from the admission valves, and they are so designed as to afford as few obstacles to the free passage of the air there- through as practicable. In the same year (1880) Lightfoot introduced an improved machine, wherein the expansion is performed in two stages. The advantage of this arrangement is that during the first stage of expansion the air can be made to deposit most of its mois- ture, after which the dry air is further expanded until it attains the required temperature and pressure. The operation of Lightfoot's machine is as follows: — The compressed air, which is partially cooled, and which when direct atmospheric air is employed is always in a condition of saturation corresponding to its temperature and pressure, is first passed into a small primary expansion cylinder, wherein it is expanded beneath a piston to a pressure that will give a final temperature of about 35'' Fahr. By this means almost the whole of the vapour held in suspension in the air is con- densed, and in the form of mist is discharged, together with Lbs. Per hour. Per cent. 45-36 lOO'OO 53-61 74-10 9-26 20-40 0-93 2-05 43-80 1-56 45 THE COLD- AIR SYSTEM. 1 33 the air, into a separator, upon the surfaces of which the said mist is deposited in the form of water, and, falling to the bot- tom, is drawn off. From this separator the dried air, which is still at a considerable pressure, is conducted to the second expan- sion cylinder, in which latter it is expanded down to the pres- sure of the atmosphere, and passed out cold and practically freed from moisture. The following table ^ gives the calculated relative amounts of vapour condensed and deposited in the various stages of cooling, with a machine on the Lightfoot system, capable oi delivering 15,000 cubic ft. of cooled air per hour, and dealing with air in a tropical climate, having an initial temperature oi 90° Fahr., and fully saturated with vapour : — Total amount of vapour entering with the air . Deposited as water in the cooler Deposited as water after first expansion . Discharged as ice in cooled air . Balance, being residual vapour still existing in cooled air . Fig. 49 is a vertical central section through the air compres- sion and expansion cylinders, and the valves of one of Light- foot's recent patterns of improved cold-air machines, which may be also classed amongst those which have afforded very satis- factory results, even when subjected to very severe tests, a is the compressor, which is of the double-acting type; and b is the expansion cylinder, which is of the single-acting type. The cylinders a and b, which are arranged tandem style or fashion, and have a common piston-rod, are placed close to- gether, sufficient clearance being left, however, to permit of the inspection or examination of the pistons being conveniently effected. An advantage of this arrangement is that the coldest portion of the expansion cylinder is placed at a distance from the hottest end of the compressor. The air-valves are circular slides formed of phosphor bronze, and are operated by eccentrics in the ordinary manner. The advantages claimed for this type of valve are, that they admit of the parts being formed very short and direct, are perfectly noiseless in action, and allow of a high piston speed being used without any injurious results. They are said to have been * " PrQceedings, Institution of Mechanical Engineers," 1881. 134 REFRIGERATING AND ICE-MAKING AIACHINERY. found to work very satisfactorily, and to have given no trouble as regards wear, even when in almost constant use for some years. The coolers consist of a pair of iron vessels fitted with sets THE COLD- AIR SYSTEM. 1 35 or clusters of solid drawn Muntz-metal tubes ^ of an inch external diameter. Through these tubes and the compressor jacket cold water is constantly circulated for cooling purposes in an opposite direction to that taken by the compressed air, by means of a force-pump driven off the crank shaft. Any water that may become deposited from the air by condensation in the coolers is blown off through suitable drain cocks. After passing through both the coolers the compressed air is reduced in temperature to within some 5° or 6° of the initial temperature of the cooHng water; the amount of which latter that is required being usually from 30 to 40 gallons for ever) thousand cubic feet of cold air discharged, or some three to four times the weight of the air. From the second cooler the cooled compressed air is conducted to the expansion cylinder B, where it performs work upon the piston, and so returns some 60 per cent, of the power that has been expended in its com- pression, and is then exhausted at a temperature of from — 70° to — 90° Fahr., or 102° to 122° of frost. The steam-engine is either of the high-pressure or of the condensing type ; in the latter case the jet or surface condenser is" placed below the cylinder, which is overhung from strong brackets on the bed-plate, and the air-pump is operated from a continuation of the piston-rod. It will be seen that this arrangement admits of a condensing engine being employed without occupying any additional space, or it allows of the engine being compounded by the addition of a second cylinder tandem fashion, in which case the condenser is preferably located below the high-pressure cylinder, and the air-pump is driven off a crank-pin in the fly-wheel. When a condensing engine is used, the cooling water, after performing its work in the coolers, is passed to the condenser. Fig. 50 is a side elevation partly in vertical central section, showing the air cyHnders of a single-acting Lightfoot cold-air machine. Lightfoot machines of the vertical pattern, with the exception that the coolers are cast in one piece with the frame, do not differ in construction to any material degree from those of the horizontal type. Vertical machines adapted to be driven by belt gearing from any convenient source of power, where same is already avail- able, have been also designed by Lightfoot, Haslam, and others. Cold-air machines have been likewise designed, and are 136 REFRIGERATING AND ICE-:\IAKING MACHINERY. manufactured by J. & E. Hall, Limited, Hick Hargreaves & Co., Stevenson & Co., Sturgeon, and numerous others : the remaining space at our disposal, however, will only permit of concluding the notice of cold-air machines by a brief description of the types made by those named. The Hall cold-air machine, when driven by a steam-engine, has three double-acting cylinders located side by side at the end of a suitable bed-plate, one of which is for steam, the second for compression, and the third for expansion of the air. The cyjinders have the usual arrangement of moving parts, that for compressing the air being water-jacketed, and the connect- Fig. 50. ing-rods working on cranks on the same shaft. The valves for the compression and expansion cylinders consist of main and expansion slides operated from two weigh-bars. These valves were in some earlier types of machines situated on the under side of the cylinders, where thej were very inconvenient to get at, but in those of later patterns, however, they are located on the top side of the cylinders, where they are more readily accessible. The coolers, which are placed below the bed- plate or frame, are arranged for surface cooling and are of the ordinary multitubular type. An interchanger was also sometimes provided, wherein the air that had done duty in the storage or cold chambers was utilised forfurtherreducingthetemperature of the compressed air. In recent machines, however, a patented form of centrifugal moisture separator is used for drying the compressed air. Hick Hargreaves' machine is of the double-acting horizontal THE COLD-AIR SYSTEM. 137 type, water being injected into the compressor at each stroke for cooling purposes. After compression it is passed through a series of receivers wherein the watery particles carried over are deposited, after which it flows into the expansion cylinder, in which it is expanded down to the pressure of the atmosphere. Corliss cut-off gear is fitted to the inlet valves of the expansion cylinder. A large snow-box is provided in the air-trunk, fitted with baffie or check plates for arresting the snow, which, as the air enters the expansion cyhnder fully saturated with moisture for its temperature and pressure, becomes rapidly filled with snow, and requires to be frequently cleared out. Stevenson's cold-air machine is also of the horizontal pattern. The compression, expansion, and steam cylinders have their pistons coupi(id to a single crank-shaft. The compression and expansion cylinders are single-acting, and are arranged to face each other, their pistons being coupled by means of T-headed rods, which form vertical guide bars, between which slides a motion block driven by the crank-shaft, and thus imparts the requisite reciprocating motion. The steam-engine is either single-acting and of the trunk type, or it may be of the simple high-pressure, condensing, or compound type. Sturgeon's horizontal pattern machine is so constructed that the compressed air is delivered into a cooler formed of sets of tubes surrounded by a circulation of cooling water, whereby its temperature is partially reduced, and it is afterwards caused to pass through some absorbent material, such as charcoal, before admission into the expansion cylinder. The main objections to all cold-air machines are: — The neces- sity for using a lubricant in the compression cylinder, which results in the air having an unpleasant odour of burnt oil. The cold air is, as a rule, employed direct, in which case the tem- perature of the chamber refrigerated rises immediately in case any stoppage of the machine has to be made for repairs or other purposes, by reason of there being no reserve store of cold that can be utilised. They are very costly to maintain and manage, entailing a large outlay for coals or other fuel, lubri- cants, and wages, and also by reason of the large quantities ot condensing and circulating water that they require. The counterbalancing advantages are : — First and chiefly, that no chemicals of any description are required, consequently their employment is not attended by constant dangers from possible explosions and fires, or loss of life through the acci- dental escape of deadly gases. Very low temperatures can be 138 REFRIGERATING AND ICE-MAKING MACHINERY. rapidly obtained by their use. Their construction is compara- tively simple, and their application is easy. The entire machine is situated externally >o the chamber or store being refrigerated, and every pait thereof is consequently accessible at all times. A matter of the greatest importance where cold-air machines are concerned is to ascertain to what degree any water that may be present, either in the form of steam or mist, or of actual liquid, may affect the heating or cooling of air, and alter the working of a cold-air machine, besides the formation of snow and ice, which unavoidably results therefrom, and Avhich is a most objectionable feature. On this head Mr. Lightfoot observes,"^ '^ The important fact to be noted in this investigation is, that air at constant pressure, having free access to water, will hold a different quantity of water in solution or steam at each different temperature ; or conversely the temperature of the ^ dew point' for any body of air varies with each quantity of water held in solution by it. The hotter the air, the more water can be held without deposit- ing. (See table on p. 241.) "Thus, if air is highly heated by compression, and water is then admitted to it, in the form of spray or injection, it will take up much more water before becoming saturated than it could have held before it was thus heated. Again, if air under compression and saturated wi b. vapour is allowed to expand, a large quantity of such vapom will condense and freeze into snow, thereby giving up a large quantity of heat to the air, which air is, in consequence, cooled less than it would have been had it been dry air to start with. This freezing is also a serious practical evil, from the deposition of ice about the valves and in the air passages, which necessitates frequent stoppages even in small machines. . . . " Various means have been devised for ridding the air more or less completely of its contained moisture by employing some chemical material, such as chloride of calcium or sulphuric acid, which is a powerful absorbent of water. But, in the Author's opinion, the use of such chemicals as are known to him is inad- missible, except perhaps for small machines, or for those work- ing under special conditions, because of the trouble which would be experienced in changing the material and evaporating off the water it has absorbed, so as to render it again fit for use." "Proceedings, Institution of Mechanical Engineers," 1881. THE COLD-AIR SYSTEM. 1 39 In a subsequent paper * the following particulars are given by the same authority as the result of his very extensive experience in the working of machines of this class : — " The amount of aqueous vapour present in the atmosphere varies from that required to produce saturation down to about one-fifth of that quantity. At any given temperature a volume of saturated air can contain only one definite amount of vapour in solution ; and if from any cause additional moisture be present , it cannot exist as vapour, but appears as water in the form of fog or mist. The temperature of saturation, or dew point, varies according to the quantity of vapour in solution; the smaller the quantity, the lower being the dew point. The capacity of air for holding moisture is also affected by pressure, a diminution in volume under constant temperature reducing this capacity in direct proportion. In the former paper reference was made to various means that had been devised for ridding the air more or less completely of its contained moisture, in order to obviate as much as possible the practical evils resulting from its condensation and freezing; this being at the tiiV-S considered one of the most important points in the construction of cold-air machinery. Since then, however, experience has demonstrated that these evils were much exaggerated, and that the condensation of the vapour and deposition of the moisture in the ordinary cooling process after compression, which is common to every cold-air machine, are amply sufficient to prevent any serious deposition of ice about the valves and in the air passages : provided, firstly, that these valves and passages are well proportioned ; and, secondly, that proper means are adopted for obtaining in the coolers a deposition of the condensed vapour, which would otherwise pass with the air into the expansion cylinder in the form of fog, and become converted into ice. Reference to the table (page 241) shows that, it the compressed air be thoroughly deprived of its mechanically suspended moisture, the amount of vapour enter- ing the expansion cylinder is extremely small. Another matter from which the mystery has now been dispelled is the meaning of the term ' dry ' air, so much used by the makers of cold-air machinery; this being a point that was just touched upon towards the close of the discussion upon the previous paper. No doubt it is still to a great extent popularly supposed that, unless the air be subjected in the machine to some special dry- ing process, it will be delivered from the expansion cylinder in * "Proceedings, Institute of Mechanical Engineers," pp. 225, 226 ; 1S86, L 140 REFRIGERATING AND ICE-MAKING MACHINERY. a moist or damp state, and in consequence be unfitted for use in the preservation of perishable food and for other purposes. But no such state could really exist; for whether the air be specially ' dried ' or not, its humidity when delivered from the expansion cylinder is precisely the same, so long as its tem- perature and pressure remain the same, inasmuch as in practice it is always in a saturated condition for that pressure and tem- perature. The difference lies in the amount of ice formed,. which of course is greater if the amount of moisture entering the expansion cylinder is greater ; but this quantity, it has been already stated, may, in the author's opinion, be brought down within perfectly convenient limits by a proper construction of the cooling vessels. In his latest machines, therefore, all special drying apparatus has been dispensed with, the air being simply compressed, passed through a surface cooler, and expanded back to atmospheric pressure." In a paper "^^ on " Refrigerating Machines," by Arthur Robert Gale, C.E., he makes the following observations on refrigerating machines of this type, pertinent to the point in question : — '* One of the chief difhculties in cold-air machines is the presence of moisture held in suspension by the atmo- sphere ; this applies especially to the open cycle machines. Moisture in the air occasions loss of efficiency in two ways. If the air enters the expansion cylinder in a saturated con- dition, when the air is cooled by expansion whilst performing work, a certain amount of vapour is condensed and thrown down — the point of saturating being dependent on the tem- perature. The vapour, in changing to the liquid state, gives its latent heat of vaporization to the air; and as the expansion of the air continues, and the temperature is still further dimin- ished, the liquid freezes and accumulates in the form of snow and ice in the valves and passages, giving up its heat of lique- faction to the air. Thus not only does the presence of moisture in the air produce mechanical difficulties, choking the air passages and impeding the action of the valves, but, for the same expenditure of energy, the cold air leaves the machine at a higher temperature than would have been the case if there had not been a superabundance of moisture in the air during expansion. " As the cold-air machine is the direct reverse of the heat- engine, so also its conditions of greatest efficiency differ from those of the latter. The maximum theoretical efficiency of a refrigerating machine may be expressed by the formula — * "Minutes of Proceedings, Inst.C.E.," vol. cxviii.. Session 1893-4, pp. 421, 422. THE COLD-AIR SYSTEM. ' 141 Ha _ T E T c - T where E is the thermal equivalent of the work of compression, Ha denotes heat-units abstracted by the system, Tc denotes absolute temperature at which rejection of heat takes place, T denotes absolute temperature at which absorption of heat takes place. From the above it follows that — i.e., in any refrigerating machine the greatest efficiency will be obtained with a small range of temperature; the greater the range the smaller the efficiency will be, other conditions being equal ; also the efficiency is increased as the lowest limit of the range ot temperature is raised. Thus a machine working between the temperatures of 100° Fahr. and 0° would, other conditions being unaltered, be more efficient than when work- ing between 60° Fahr. and —40° Fahr. These remarks are applicable to any system of refrigeration, and are not peculiar to the cold-air machine." For some time it was very generally supposed that many kinds of provisions of a perishable nature were liable to receive damage from the snow held in suspension in the cold air from these machines, and it was this fear of injurious effects which prompted inventors to design those forms of special drying apparatus intended to remedy this defect, such as the Bell- Coleman interchanger wherein the air is dried by passing it through a series or set of coils situated in the chamber cooled by the machine; of the improved form of the above designed by Haslam, wherein the interchanger is cooled either by the spent cold air on its leaving the chamber wherein it has been utilised, or by the cold air as it passes out of the expansion cylinder ; the Lightfoot machine, wherein the expansion is performed in two stages ; or of Hall's centrifugal moisture separator. Hence the term " dry-air refrigerator." This objection to the cold-air machine arose, however, from a fault the evil effects of which, it has now become evident, have been undoubtedly much exaggerated, as in practice no such damaging results to the contents of the stores or chambers are experienced as it was supposed and predicted would ensue, although of course the snow that is formed in the manner *bove described is an undeniably objectionable product. li a 142 REFRIGERATING AND ICE-MAKING MACHINERY. cold-air machine be worked on the principle of exclusion of the aqueous vapour, after a few cycles of operations the air will have become dry, and will thenceforward work like a true gas. Owing to their compactness and simplicity, to the non- requirement of any chemicals, and to the great facility of appli- cation, cold-air machines are found to be very suitable for marine installations, and for this purpose they are extensively employed. They are also, however, in use to a considerable extent for refrigerating cold stores or chambers for the preser- vation of provisions of a perishable nature. An objection, however, to machines of the Bell-Coleman type, wherein the air is partially cooled during compression by the injection of cooling water into the compressor, is experi- enced at sea, by reason of the corroding action of the salt- water, in addition to the loss of efficiency common to all machines of this class. Considerable difficulty is also expe- rienced in tropical climates, where, with the cooling water at about 90° Fahr., the moisture-laden air would be delivered into the cooling pipes at a temperature of 95° Fahr., or more, and the absolute pressure would be about 65165. per sq. in. Now, as there is, as Mr. Lightfoot observes,* " precisely the same amount of dry cold air circulating outside the cooling tubes in a given time, as there is warm compressed air within, it follows that by whatever amount the temperature of the internal air is reduced, by an equal amount must that of the external air be raised. But, in addition, the internal air has vapour mixed with it, which, as the temperature falls, gives off heat, measured not only by the reduction in its sensible temperature, but by the latent heat of vaporisation ; and this heat also has to be taken up by the external air. It will be found that, assuming each pound of internal air, with its proportion of vapour, to be reduced to 42° Fahr., the pound of external cold air, which has to take up all the heat due to this reduction, will be raised in temperature by 84° Fahr." Instead of using the spent air for cooHng purposes, the cold air from the expansion cylinder may be applied direct to the cooling apparatus ; but in this case difficulty would be experienced from the deposited moisture inside the tubes actually feezing from the intense cold of the external air, a difficulty which, it appears, has often occurred with this ap- paratus. This, apart from the mere obstruction of the pipes, would involve a further sacrifice of cold, owing to the liberation of the heat of liquefaction. * "Proceedings, Institute of Mechanical Engineers," 1881. ard.* Haslam.t Coleman. 5- 27 25i(2-cy.) 28 22 i9i n 21 18 36 24 62 72 63-2 THE COLD-AIR SYSTEM. T43 The following table gives the results of test experiments made with modified Giffard, Haslam, and Bell-Coleman ma- chines, and designed to deliver about 15,000 cubic ft. of cold air per hour, when running at a spred of 60 revolutions per minute:— Bell- Giffard.* Haslam.t Cc Diameter of compression cylinder, in ins. . ,, expansion ,, ,, Stroke of each ....,, Revolutions per minute .... Air pressure in receiver (absolute), in lbs. per sq. in. ....... 65 64 61 Temperature of air entering compression cylinder (containing vapour up to 88 per cent, of saturation) 52°F. ,, 65 1 F. Temperature of air discharged from compres- sion cylinder 267° F. Temperature of compressed air admitted to expansion cyhnder . . . . . 70°F. Temperature of air after expansion . . — 82°F. — 85°F. — 52='F. Work done in compression cylinder, from diagram . . . . . . . 43T2h.p. Work given oiF in expansion cyhnder, from diagram . . . . . . . 28-05h.p. Difference in work done in compression cylinder, and work given off in expansion cyhnder 15 "07 Diameter of steam cyhnders, in ins. . .12 ,, trunks in cylinders, in ins. . 10 Stroke of trunks . . ,, -15 Initial steam pressure in cylinders (absolute) per sq. in 55 lbs. Work given off in steam cylinders, from diagram 24-6 h. p. Initial temperature of coohng water . . 57" F. Final „ ,,,,.. 145" F. Quantity of coohng water passing per minute in lbs. . . . . -9*25 Work lost in heat taken off by cooling water 19 h.p. I, h. p. in compression cylinder . . • 43'i 346"4 I24'5 „ in expansion cylinder . . . 28*0 176' 2 58-5 The proper management of cold-air machines is far simpler than that of those working on other principles, the exact treat- ment of each particular machine, however, varying of course somewhat with the make. In all machines, however, the parts most liable to give trouble are the valves, and these, as also the pistons and slide valves, should be periodically tested, and any defect promptly remedied. * " Proceedings, Institution of Mechanical Engineers," iSSl. t *« Proceedings, Manchester Society of Engineers," 1894. X Professor Schroeter, '* Untersuchungen an Kaeltemaschieren verschie- dener Systeme," 1881. CHAPTER IX. Refrigeration. The class of machines described in the last cliapter, viz., those wherein the abstraction of heat is effected by first compressing air and afterwards permitting it to expand, or cold-air machines, are, as already mentioned, somewhat extensively applied to the preservation of meat and other comestibles of a perishable nature. Those wherein the evaporation of a volatile liquid is employed to produce the cold are likewise in use to a con- siderable extent for this purpose, and it would be difficult to decide which type of apparatus is the best suited for a land installation, as favourable results are obtained from the use of both. Much can be said, however, in favour of cold-air ma- chines, in cases wherein the cost of fuel is not a matter of vita!, importance, and, as already mentioned, they possess certain qualities \vhich seem to render them especially advantageous for marine installations. For breweries, chemical works, paraffin oil and other works, it is probable, on the other hand, that those machines operating to produce cold by the evaporation of a volatile liquid, especially ammonia machines, will be found the best. When a cold-air machine is employed for refrigeration, the cold air is, as a rule, admitted to the cold chamber or chill room through ducts placed near the ceiling, and after it has done its duty is conducted back again to the compressor, wherein, after being mixed with a sufficient amount of fresh air, it is again compressed. The most advantageous method of conveying the cold air from the machine to the chill room or cold store or chamber, is by means of wooden trunks or conduits discharging into the latter through an inlet situated at or near the ceiling at one ex- tremity tliereof, the used or spent air being withdrawn through a similarly situated outlet and conduit at the other extremity. REFRIGERATION. 1 45 All abrupt rises or falls or bends in the air trunks should be avoided, and their length should not be excessive, as the loss experienced through the rise in temperature of the air in the latter case would be very considerable. The extreme limit of distance to which it is advisable to convey the cold air through these conduits is 200 ft. When carcasses are to be congealed, the temperature of the freezing chamber or room should be maintained at about 10° Fahr. ; as has been already stated, however, the cold should on no account be applied too rapidly at starting, but gradually, so that the internal heat may be first sufficiently reduced, to avoid injury to that portion of the meat, before the outer surface becomes frozen. For after preservation of frozen meat it is sufficient to keep the atmosphere of the chamber or store down to a temperature of about 15° or 18° Fahr.; it should not, however, be allowed to rise above 20° Fahr. According to Colonel B. H. Martindale, C.B., R.E., the general manager of the London and St. Katherine Dock Com- pany, in 1886 they had 56 refrigerating chambers in two vaults, the smallest of which chambers had a cubic content of 2,273 ft., and the largest thereof of 9,280 ft., the total content of the said 56 chambers being something over 183,000 cubic ft. The carcasses of the sheep averaged in weight 56, 60, and 72 lbs. each ; and the whole of the chambers completely filled would contain about 59,000 sheep of the first weight, 56,000 of the second, and 44,000 of the third ; in practice, however, a space or clearance had to be left for gangways, and for separa- ting difterent marks, for which a deduction had to be made from the total storage capacity, and taking the shipments as they chanced to arrive, tlie above space was equal to the stor- ing of the carcasses of about 44,000 sheep. The cold-air machines employed in connection with the 56 chambers in question comprised four Haslam 60,000 cubic ft. machines, and three Hall 30,000 cubic ft. machines, supplied with steam from three multitubular boilers of the marine type, and four boilers of the locomotive type, the former having been found in practice to be the best. One of the Haslam 60,000 cubic ft. machines, worked on 15 chambers, having a total capacity of 48,000 cubic ft., and capable of storing 11,000 carcasses of sheep averaging in weight 72 lbs. each, but which storage capacity was reduced by gangways, &c., to between 8,000 and 9,000. The engine was kept running twenty hours 146 REFRIGERATING AND ICE-MAKING MACHINERY. out of every twenty-four, the said stoppage including the time required for clearing the snow from the valves, snow boxes, and air-trunks. The average speed was 80 revolutions per minute, at an air pressure of 44 lbs. per square inch, giving a tempera- tare of — 70° in the snow boxes, and keeping the temperature of the chambers down to from 15° to 18° Fahr., which was found in practice to be about the best temperature to keep the meat at. Better results were obtained in proportion to the fuel consumed, by working at an air pressure of about 44 lbs. per square inch, instead of 50 lbs. and upwards ; not giving such a low temperature in the snow boxes, but about — 50° Fahr. instead of — 60° or — 70*^, and delivering a larger volume of cold air into the chambers. The proportionate rise in tem- perature was then much less between the delivery from the expansion cylinder and the distant chambers. Twenty-four chambers, with a capacity of 90,000 cubic ft., were worked by two Haslam 60,000 cubic ft. machines, running at an average of 70 revolutions per minute, with an air pressure of 40 lbs. per square inch, the temperature in the snow box being — 55° Fahr. The temperature of the chamber next the machine could, as a rule, be kept at a sufficiently low temperature with but little opening of the delivery ports in the air-trunks, and almost without admitting air at all, as the mere passage of the said air-trunks through it kept it nearly cool enough. The greatest care was taken in regulating the delivery and return air-ports or apertures, gradually increasing the area of both in proportion to the increased distance from the machine ; the greatest distance to which the cold air was conveyed being 180 ft. The practical result of the observations taken, which extended over some time, was that the rise of temperature in travelling was 1° Fahr. for every 18 or 20 ft. travelled; but this, of course, must not be taken for more than the result arrived at from general working under existing conditions. It was likewise found that from i to i^ cubic ft. of cold air per hour would keep cool — say at 18° Fahr. — i cubic foot of storage at a distance not exceeding 180 ft., or say, at an average distance of 90 ft. from the machine. The first amount named, viz., I cubic foot of cold air per hour to each cubic foot of storage, was the result arrived at during temperate weather, and this, it is estimated, would most probably be amply suffi- cient were the chambers fully stored with carcasses, and left entirely undisturbed ; but as this is not possible in practice, an REFRIGERATION. 1 47 allowance has to be made for the opening of doors for the purpose of deliveries and so on ; and the second amount, or i^ cubic ft. of air per hour for every cubic foot of storage that it was desired to keep down to, say, i8° Fahr. was found to be about correct for general practice. The coal consumption, he stated, was, for three machines, giving out nominally 120,000 cubic ft. of air (one 60,000 cubic ft. and two 30,000 cubic ft. machines), 4^ tons of coal in twenty hours ; and two 60,000 cubic ft. machines, working under practically similar conditions, had a like consumption. The coal used w^as ordinary Welsh coal, costing about i6s. 6d. per ton. When refrigerating machines wherein the cooling is effected by the evaporation of a volatile liquid are employed, the refri- geration can be conveniently effected in three ways, viz. : — First — by cooling a non-congealable salt brine, and then pumping it through a system of pipes, or of open troughs in the chambers. Secondly — by causing a current of air, generated by means of a fan or otherwise, to impinge against surfaces reduced to a low temperature by the expansion of the refri- gerating agent itself, or by an internal circulation of cooled brine, and conducting the said cold air to the refrigerating chambers. And thirdly — by expanding the gas direct through pipes placed in the said chambers. The main advantage claimed for the first of these plans is that it admits of the machine being stopped, and when an in- dependent brine pump is employed, the brine wherein a large reserve of cold is stored up, can be continued in circulation for a considerable time before any thawing from rise of tempera- ture and consequent dripping will take place from the pipes. Fig. 51 is a vertical section through the end of a refrigerating chamber as designed by the Pulsometer Engineering Com- pany, Limited, showing an arrano:ement of cooling pipes on the brine circulation system. The pipes are of galvanised wrought iron, which, being very much lighter and thinner than those formed of cast iron, ensure the maximum amount of head room, and thereby enable a considerable amount of space to be economised. The agent employed in the brine circulating system consists of a solution of chloride of sodium or common salt,* or of chloride of calcium,* chloride of magnesium, or any other * For proportions. &c., of these solutions, see p. 253. 148 REFRIGERATING AND ICE-MAKING MACHINERY, suitable solution capable of standing very low temperatures without congealing. To extract or absorb the heat from the REFRIGERATION. 1 49 orine, the simplest and best method is undoubtedly that most commonly employed, which consists in enclosing it in a tank of ample dimensions fitted with vertical coils of jjipes, through which the chilled liquefied ether, ammonia, or other volatile refrigerating agent, circulates, vaporizes or gasifies, expands, and subsequently returns therefrom in the form of a gas or vapour to the compressor, in one system ; and in the other, in the form of a strong solution to the generator. In some instances expansion valves or cocks, such as one of those illus- trated in Figs. 32 to 35 (page 80), are fitted to the inlet ends of the said submerged coils. The brine, being thus deprived of a large portion of its heat, is then drawn away from this refrigerating or cooling tank or vessel by the brine circulating pump, and is forced through the system of cooling pipes in the refrigerating chamber or cold store. A plan of chilling and freezing by a circulation of cold brine on the wall system has been patented by Hall. In this arrangement the congealing or freezing room or chamber is fitted with parallel hollow or cellular walls constructed of steel or iron plates, and situated at short intervals apart. The carcasses to be chilled or frozen are hung in the spaces or passages left between these walls, which latter can be main- tained at a very low temperature by the cold brine circulating therethrough. An advantage possessed by this method is, that, owing to the extensive surfaces afforded by these hollow or cellular walls or plates, an intense cold can be rapidly produced, and the heat very expeditiously abstracted from the carcasses, which are thus quickly frozen or congealed. On this account, as the space taken up by the said hollow walls is so trifling as not to necessitate any increase in the dimensions of the freezing chamber for a given number of carcasses, the proportion usually allotted to the latter may be reduced, and a saving of labour and of depreciation through handling is also effected. The carcasses when frozen are at once removed to cold stores or chambers kept at a proper temperature for preserving the contents, by a circulation of brine through a system of pipes arranged near the ceiling ; or air, cooled in the machine-room, may be circulated therethrough for a like purpose. On the other hand, however, these hollow or cellular walls would seem to be open to the objections that they are far more difficult to maintain tight and free from leakage than a system of pipes, and, moreover, that the shallow space left between the walls is liable to become choked by any foreign matter in 150 REFRIGERATING AND ICE-MAKING :MACHINERY. the brine, and from deposits from the latter. The first of these objections renders this plan unsuitable for the direct expansion system. In order to faciUtate and hasten the operation of chilling and freezing, and lessen the handling to which it is necessary to subject the carcasses, an arrangement for slowly traversing the latter through the freezing or congealing chamber or room has also been devised by the same inventor, wherein an endless chain provided with hooks at proper intervals for hanging the carcasses, and operated by suitable gearing, is provided. The open trough system has been already alluded to, and it is one of great simplicity, and is frequently used for the hog cooling rooms in bacon factories. Two, three, or other suit- able number of troughs are usually placed in line, vertically, one above the other, over each hook or hanging rail, and the flow of brine can be regulated by any well-known and con- venient means. A large surface of cold brine is in this system advantageously exposed for absorbing heat ; on the other hand, however, the open troughs have the disadvantage of taking up a very considerable amount of valuable space. The cooling pipes are arranged in the chilling, cooling, and curing rooms of bacon factories in a number of other different ways, the system having frequently to be specially adapted to the existing buildings. Sometimes the said pipes are placed in the form of coils in a separate chamber provided in the ceiling of the main room or chamber (as shown in Fig. 64, page 178), and air, admitted through suitable apertures from the room beneath, or by means of ventilators, and cooled by passing over the surface of these coils, is rapidly circulated through the said room. A somewhat similar arrangement of brine or cooling pipes is also often employed in beef and other meat rooms. The advantage of this plan is that it effectually prevents any dripping and moisture in the chill room. In the folding plate facing this page, the refrigerating pipes or coils and circulating fan are fixed in a separate compartment quite distinct from the cold rooms, but connected therewith by trunks or ducts. The cooling is effected by the constant circulation through the chill or meat rooms of a current of air that has first been cooled by passing it over the refrigerator. The air is washed and purified by being passed through a series of sprays of cold brine, and then over the refrigerator, by which it is dried and reduced to any desired temperature. The fan draws the air from the rooms through the suction trunk, and returns it by the dd- :hill room. REFRIGERATION. 150^ livery trunk after it has passed through the refrigerating chamber and been washed, cooled, and dried ; the air thus becomes colder, and is purified each time it passes over the refrigerator. Another method of arranging the cooling pipes in a chill room is to provide coils on the sides thereof, or where the chamber is of considerable dimensions, in rows placed verti- cally at suitable intervals lengthways of the latter, the carcasses being suspended by hooks in the usual manner from meat or hanging rails, situated overhead, between the said coils. When the refrigerating pipes are placed directly in the cold store, suitable drip trays (as shown in Fig. 62) can be provided if required, to catch any water falling from the said pipes, upon the exterior surfaces of which the moisture present in the atmosphere of the room becomes condensed, either in the form of water or of hoar frost. In the British patent of F. B. Hill, No. 16253 of 1889, is described an arrangement in which, as shown in Fig. 51^, the refrigerating apparatus is located on a iioor above the cooling chamber. Ih's arrangement, moreover, permits the circula- tion of the cooling medium by gravity, so that the use of pumps or other machinery for effecting such circulation can be dis- pensed with. H is the refrigerator tank ; H^ is another tank or vessel which is preferably arranged at a lower level than the refrigerator-tank, and is connected therewith by means of pipes J in s.uch.a manner that a constant circulation of the brine or other non-congealable liquid from one tank to the other will be maintained by gravity during the refrigeration of the liquid. It is stated by the inventor that, by the use of tanks con- nected in this manner, the reservoir or store of cold is greatly increased. The bottom of the coohng tank h^ may if desired serve as the top of the chamber to be cooled, as shown in Fig. 41^, page 113/ The bottom of the tank h^ is formed with a series of V-shaped portions or corrugations H^, and suitable gutters or channels K are arranged beneath the tank, so that any moisture collecting on the underside will flow to ihe lower edges of the corrugations or V-shaped portions, and will fall into the said gutters or channels, whereby it will be conducted away to any convenient place. The dripping of moisture from the under surface of the tank into the room or chamber to be cooled is thus avoided. This arrangement also increases the I503 REFRIGERATING AND ICE-MAKING MACHINERY. area of cooling surface and the strength of the bottom of the tank. In a later patent, viz., No. 20509 of 1890, the same inventor describes means for removing snow or hoar-frost from the B a // Fig. 51a. refrigerating surfaces used for cooling air, which consists in the employment of rotating screw-blades or conveyors, or of annular or other suitable scrapers, or brushes arranged to move to and fro, or up and down, in contact with the surfaces to be cleared. These screw conveyors, scrapers, or brushes, are placed within or outside, or both within and outside, the refrigerating tubes or chambers. . F. N. Mackay, No. 16745 ^f 1886, provides for the com- bined utilization of cold air from an air expansion machine and brine cooled by an absorption or compression machine. The rooms or chambers are partly cooled by the cold air, and the brine from the latter machine is circulated through an arrange- ment of pipes in the cooling chamber, to which brine pipes corrugated metal sheets are attached to increase the refrigerating effect. Or the corrugated metal sheets may be formed into narrow chambers to receive the brine directly. To increase the effective surface of cooling pipes F. S. Thomas, No. 2568 of 1888, forms them with four concavities, REFRIGERATION. I51 or approximately star-shaped in transverse section, and also employs lugs or ribs. One advantage of the third system, or that wherein the refrigeration is effected by expanding the gas or vapour direct through the system of refrigerating pipes in the stores or chambers, is that a more economical and rapid cooling is effected than with the brine circulation; another is the simplification ot the apparatus and the reduction in the first cost thereof. To counterbalance which advantages, however, there is the danger to human life, of damage to the contents of the refrigerating chambers, and of fire, should any leakage of the gas or vapour from the cooling pipes take place, and also the impossibility of shutting down the machine even for a few minutes without the said pipes commencing to drip. So far, however, as ammonia is concerned, the fears of any deterioration in the quality of fresh meat, which is being frozen or preserved, resulting from any accidental leakage of the pipes, would seem to be totally groundless, judging from the results of recent practice, and the opinions of experts. On this head the following extract from an article published in the Scientific American^ in 1889, is of interest : — " Some years ago Dr. B. W. Richardson, in a communication to the Medical Society, called attention to the antiputrescent properties of ammonia, and showed that blood, milk, and other alterable liquids could be preserved for a long time by adding to them certain quantities of solution of ammonia ; and solid substances, such as flesh, by keeping them in closed vessels filled with ammonia gas. Some doubts that would appear to have been raised as to the results reported, on the ground that ammonia was itself a product of decomposition, induced Dr. Gottbrecht, of the University of Greifswald, to repeat the experiments with the result of practically confirming all Dr. Richardson's statements. After some preliminary experiments, in which animal matter placed in 5 per cent, of ammonia solution was found free from putrescence after nearly two years, ammonium carbonate was used in place of the free alkali for the sake of convenience. The first experiment made with the washed intestines of freshly killed pigs, showed the power of ammonium carbonate to retard putrefaction to be directly dependent upon the concentration of the solution, a i per cent, solution retarding it until the third day, a 10 per cent, solution until about the sixtieth day. When added to gelatine in which putrefaction had already been set up by inoculation. 52 REFRIGERATING AKD ICE-MAKIXG MACHINERY. modified 1 the it was found that a 5 per cent, solution so conditions that the putrescence ceased, and a 2-k per cent, solution inhibited the development of bacteria, so that the liquefaction of the gelatine was practically stopped. Other experiments showed that in an atmosphere impregnated with ammonium carbonate meat could be kept for six months, and at the end of that time remain nearly unaltered." When chambers are refrigerated on the direct expansion system it is nevertheless essential that the system of pipes em- ployed, which can be arranged on any ot the plans for brine circulation that have been already mentioned, should be such as to reduce as far as practicable to a minimum the chance of leakage taking place at the joints, cocks, valves, &c., as independently altogether of any possible damage to the contents of the stores or chambers, it is highly desirable for economical reasons, that as little as possible of the ammonia be lost. The Pontifex joint for ammonia has been already briefly described when dealing with his patent of 1887. Amongst the numerous other special joints mention may be made of those of De La Vergne and Kilbourn. REFRIGERATION. 1 53 Figs. 52 and 53 illustrate, in perspective and vertical central section, the De I.a Vergne patent pipe joint. To ensure a tight joint to withstand high pressure the flanges are connected to the pipes both by screw threads and solder, the latter being run into the annular recesses or clearances shown above the threaded portions, the surfaces of which are well tinned. The joint between the flanges is formed by an annular pro- jection upon the one lilting into a corresponding groove formed in the other, which, when the nuts are screwed up upon the bolts for connecting the said flanges, is pressed home and bears upon a suitable packing ring inserted into the bottom of the said corresponding groove or recess, and thus forms a perfectly gas-tight joint. Similar screwed and soldered joints M 154 REFRIGERATING AND ICE-MAKING MACHINERY. are likewise employed wherever it is necessary to use a return bend, elbow, tee, cross, or other connecting piece. The fittings are either made of malleable iron or steel. The result of covering the thread of the pipe with solder, and running the latter into the above-mentioned annular recess or clearance, and thus forming a compound screwed and soldered joint, is, that what is otherwise the weakest part of a length of piping becomes the strongest. It is stated by the inventors that it has been invariably found that when the usually applied test of I, GOO lbs. hydrostatic pressure to the square inch is overrun, the pipe rips open before the joint gives out. Fig. 54 is a vertical central section illustrating Kilbourn's Eig. 54- patent joint, which is especially intended for use where it is necessary to set tubes or pipes in places where an expander cannot be used, or where sweating or soldering Is requisite to make a perfect gas-tight joint adapted to withstand very high pressures. As will be seen from the illustration the extremity of the pipe is flanged and secured in a recess in the plate by means of a nut or collar, after which solder is run round it. Where the plate is of insutficient thickness to allow for a depression being left for the said solder a rib is formed thereon, as shov/n. In this manner the inventor claims that the pipe or tube can be so secured to a tube plate or its equivalent that it will be perfectly firm and rigid, and that the solder will retain its hold against all ordinary or usual contingencies, whilst at the same time forming a perfectly gas-tight joint. In Fig. 55 is shown Kilbourn's patent coupling for connecting together different lengths of pipes, or forming joints between the latter REFRIGERATION. 155 and their connections, where fluid-tight joints to withstand very high pressures are demanded. The usual internally screw- threaded socket is chamfered or bevelled at its extremities, and caps having internally chamfered shoulders and bored to fit over the pipes, and over the said socket, are forced against the latter by means of back- nuts, so as to compress the packing rings or jointing ma- terials, placed between the chamfers on the socket and caps, as shown, and thus form a perfectly gas or fluid-tight joint. The De La Vergne patent improved form of stop-cock for ammonia gas is illustrated in Fjgs. 56 and 57, which show ver- tical central sections through the shells or casings of a 2 1- in. and a i-in. cock, the plugs being left in elevation. As will be seen from the drawings, the square for operat- ing the plug is, contrary to the usual custom, placed at the small end thereof, the latter being pressed to its seat by a spiral spring inserted between its large end and a cap bolted up to the shell or casing, and having an annular projection adapted to engage in a corres- ponding groove formed in the latter, and wherein is provided a lead or other washer. Similar means for forming a gas-tight joint are provided at the small end of the said plug, and in this manner the escape of any fluid into the chamber that might chance to pass the plug, is pre- vented. The even and constant pressure of the spiral spring maintains the plug always on its seat, and prevents any grit or other impurities from getting between the surfaces and cutting Fig. 55. 156 REFRIGERATING AND ICE-MAKING I^IACIUNERY. or abraiding them. The shell of the small-sized cock or valve (Fig. 57) is of slightly modified form. The Kilbourn patent stop-cock is provided with a cone, gland, nut, or sleeve, and collar, so constructed and combined that by turning the gland nut in the one direction the cone will be forced into and held in its seating, whilst on the other hand Fig. 56. by turning it in the other, or opposite direction, the said cone will be started from its seating. Fig. 58 is a perspective view of a disc or gill which is formed in halves, one of which is shown removed in Fig. 59. The two halves or parts of the disc are adapted to be secured together upon the pipe by means of iron clips which press them against the said pipe. These discs are fixed at regular intervals upon the cooling or refrigerating pipes in the cold stoves or chambers, after they are all put up, and, according to the inventors, their effect is to increase the cooling surface to such an extent that REFRIGERATION. 157 only one foot of pipe is found requisite where four would be necessary without them. Ammonia, both in a liquid and gaseous condition, has no chemical eftect whatever upon iron, consequently the cooling pipes require no protection except upon the exterior, which should receive a coat of paint every year to prevent them from rusting. So long, however, as the pipes are coated with snow or ice no corrosion will take place, even externally, as they are thoroughly protected thereby from the oxidizing effect of the atmosphere ; when, however, they are subjected to alternate freezing and thawing, as is usually the case during actual work, Fig. 5^ when the chambers or stores are alternately in and out of use, they must be protected as above mentioned. There is not the least doubt but that the direct expansion system is, as has been before mentioned, more economical than the brine circulation system. This will be obvious when it is remembered that every transmission of heat must of necessity entail a loss of efficiency. A far higher evaporating pressure can be maintained in direct pipes than in evaporating coils in a brine tank, whilst at the same time they have still within them a far lower temperature than in the latter. The result of this is that, in the compression system, the gas is sucked into the compressor at a greater back pressure when direct expansion is employed, and a far larger amount of efficiency is obtained. The cold, moreover, being produced exacdy where it is required, there is practically no waste. 158 REFRIGERATING AND ICE-MAKING MACHINERY. In the brine system, on the other hand, the large refrigerating or cooling tank is exposed to the atmosphere, and even when insulated as perfectly as possible, a considerable amomit of heat is unavoidably absorbed, which is, of course, a total loss ; Fig. 58. copsiderable fuel consumption is moreover required in the brine circulation system, for the power consumed in pumping the large quantities of brine through the system of pipes in the refrigerating chambers or cold stores, which pipes some- REFRIGERATION. 59 times run to many thousands of feet in length, thus giving rise to a large amount of friction ; and besides, after being in use for some time, they become internally coated with rust, and with a slimy deposit, which not only produces a considerable increase in the amount of the said friction to be overcome in driving the brine through them, but furthermore forms a sort of non-con- ducting coating, and les- sens, to an appreciable extent, the heat-absorbing qualities of the system. Altogether it is not im- probable that the entire loss through the addi- tional consumption of fuel entailed from all the above causes does not, in many instances, fall far below 25 per cent, of the entire amount. At The Southampton Docks four cold stores or chambers, having a joint capacity of 47,000 cubic ft., are refrigerated on the direct expansion system by a 6 in. by 12 in. double- acting De La Vergne ma- chine, having two com- pressors driven by a 10 horse-power gas-engine. The proper insulation of the stores or chambers has been very carefully attended to, and a few hours' working out of every twenty-four is stated to maintain the temperatures sufficiently low. Apparatus is also in use which is so arranged that the refrigerating coils or pipes are placed in a separate com- partment connected with the refrigerating chambers or cold stores, and air, having been cooled in the firsts is passed I bo REFRIGERATING AND ICE-MAKING MACHINERY. into the latter, the circulation being kept up by means of a fan or blower. The refrigerated air is sometimes first washed and freer] from snow by passing it through a shower of cold brine. This arrangement is possessed of one of the advan- tages derived from the use of cold-air machines, viz., that every part of the apparatus is situated externally to the refrigerating chamber or cold store, and consequently acces- sible at all times. Dripping from the refrigerating pipes when the machine is stopped for a short time, and the temperature of the said chamber or store rises slightly, is also avoided. On the other hand, however, there is a considerable loss by reason of the absGq:)tion of heat by the cold air on its way fiom one chamber to the other; an increased cons-urnption of fuel, owing to the power required to work the fan or blower for keeping up the air circulation ; and finally the loss of valuable space taken up by the chamber required for the purpose of cooling the air. The plan wherein air, refrigerated by contact with brine- cooled surfaces, is passed into the chambers or stores, is evidently still more costly, inasmuch as there are not only the losses entailed from the above-mentioned sources, but, further- more, that caused by another transmission of heat. CHAPTER X. Construction and Arrangement of Rooms and Cold Stores and Chambers for Freezing and Preserving Provisions. The knowledge of the conservative action of cold upon organic substances is probably as old as the existence of human beings, and has been constantly utilised to preserve from putrefaction various alimentary substances. Attempts were primarily frequently made to produce a refri- gerated atmosphere by means of ice, but the results obtained were far from satisfactory, the atmosphere of the stores or chambers so cooled being more or less saturated with moisture from the melting ice, and the meat preserved therein assuming a musty and disagreeable flavour. The possibiHty, however, of successfully keeping meat in artificially cooled stores or cham- bers dates only from the invention of Charles Tellier's machine and brine circulating system in 1873, by which he was enabled to create a cold dry atmosphere, wherein organic substances could be maintained constantly at that temperature which is found to be preservative. It is therefore an art of comparatively modern origin. For the preservation ot meat the machines in most general use are those working upon the ammonia compression, or upon the absorption system, and cold-air machines. Ether machines, however, are also used, though to a less extent, and they have the advantage over ammonia machines, of a low working pressure in the condenser, which, as already mentioned, is found to be very advantageous in hot climates. In freezing carcasses for transportation, the cold is best applied gradually at first, so as to ensure an even freezing throughout, and prevent damage to the inner portions of the meat, by the freezing of the external surfaces thereof before the internal heat is sufficiently lowered. \\ hen frozen or congealed 1 62 REFRIGERATING AND ICE-MAKING MACHINERY. a temperature of at least as low as i8° Fahr. should be main- tained. For cooling ships' holds, cold stores or chambers, and other similar purposes, temperatures varying from 15° to 55° Fahr. are required, in accordance with the material being dealt with, an even temperature in every part being abso- lutely necessary. When freezing carcasses they must be hung at such distances apart as to admit of a ready circu- lation of the cold air round them taking place ; for storage for transportation, however, it is recommended to pack them as tightly together as possible, provided no injury through bruising be caused, and that a sufficient clearance or free space be left for the circulation of the cold air between the said carcasses and the inner lining of the storage chamber. The temperature of cold land stores or chambers for storing and preserving un- frozen meat need not be lower than 25° Fahr., but should not rise above 30° Fahr. When the meat is frozen, however, as it must be when it has to be kept for any length of time, it may advantageously be maintained at as low a temperature as 15° Fahr. The arrangement of the cooling pipes in cold stores for pre- serving provisions of a perishable nature requiring to be kept at various temperatures between 25° and 45° Fahr,, in accor- dance with the description of the said provisions ; or of those in chambers for freezing or congealing meat and keeping it frozen, which require to be maintained at temperatures of between 10° and 18° Fahr., according to the work demanded, only differ from other installations in the particular disposition and number of the said pipes, the chambers intended for the latter purpose being, of course, fitted with the greatest number. When the direct expansion system is in use the pipes should invariably be of wrought iron, and even where the brine circu- lating system is employed they should preferably also be of the latter material in the case of freezing-chambers, as the heat from the said chambers passes more readily through the thinner walls of the smaller wrought-iron pipes. Besides which there is, as has been already mentioned elsewhere, a considerable saving of space. The atmosphere of cold stores in some instances should be kept as dry as practicable ; whilst in others a certain amount of moisture is desirable, as, for instance, when used for preserv- ing fish which are injured by the air being too dry. For preserving meat for comparatively short periods the best tem- perature is from 30° to 40° Fahr., as most descriptions are ARRANGEMENT OF ROOMS AND COLD STORES. 1 63 injured to a greater or less extent if permitted to freeze, by the bursting of the vesicles of which flesh is composed. When, however, it is required to be preserved for a longer period than, say, three weeks it is absolutely essential that the meat should be frozen, otherwise a slight decomposition will take place, and it will become greatly deteriorated. The efficient insulation of a freezing room or of a cold store, or refrigerating chamber, is a matter of very greafe importance from an economical point of view\ This will be apparent when it is remembered that when once the contents of the said cold store or chamber are reduced to the requisite tem- perature, the entire work required of the refrigerating machine will be only that which is necessary to neutralise the heat that passes through the walls, floor, and ceiling thereof, from the exterior. Consequently, the more perfect the insulation, the less the machine will be called upon to work, and naturally in a corresponding ratio also w411 be the saving effected in fuel, wear and tear of the working parts, and in attendance. The means adopted for insulation consist in lining the room, or, in the case of a marine installation, the hold of the vessel, with some material forming a very bad conductor of heat. The exact method of carrying this out, as also the nature of the non-conducting material employed, must necessarily be considerably varied according to the circumstances of each case. In New Zealand and Australia pumice is much used. Mr. Lightfoot recommends as a fairly good protection an outer and an inner layer of tongued and grooved boards, i in. or i^ in. thick, with a 9 in. space or clearance between them filled with charcoal, or in some cases preferably with silicate cotton or slag wool. In France and Germany cork is used with marked success as a non-conductor, and it is evidently a substance exceedingly suitable for the purpose in question, being a material very impervious to heat, and capable of withstanding moisture. Either ordinary cork cut into thin slices, or refuse or waste cork, from other industries, thoroughly ground up or dis- ><;^ integrated into a coarse powder, is employed, the former being the best but the most expensive. Various other substances such as asbestos, cotton-wool, sheep's-wool, pine-wood, loam, gas works breeze, coal ashes, sawdust, hair felt, lamp black, mica, paper, fine cinders, pitch, &c., are likewise employed for purposes of insulation. A number of differer^t compositions have also been tested and 1 64 REFRIGERATING AND ICE-MAKING MACHINERY. used as heat insulators, amongst which may be mentioned the fol- lowing : — Composition of fossil meal, composed of 60 per cent, of washed white German kieselguhr, and 40 per cent, of binding material ; composition of kieselguhr from German mines, with 10 per cent, of binding matter, such as fibre, and mucilaginous extract of vegetable ; cement composed of blue clay mixed with flax ; jute, and woollen waste, or cow's hair, in equal pro- portions ; fibrous composition of fine blue clay mixed with flax, hemp, rope^ jute, cow-hair, and woollen w^aste ; and a papier- mache composition composed of paper-pulp mixed with clay and carbon, together with hair and fragments of hemp-rope. In choosing a substance other considerations besides its good insulating powers must be taken into consideration, such, for instance, as its capacity for withstanding moisture. This latter quality is of the utmost importance, inasmuch as at very low temperatures moisture from the air is very readily absorbed by many substances, and fermentation, rotting, and decay Avill result therefrom. It is for this reason that cork- forms so desirable a material for insulating purposes, although surpassed in non-conductibility by some others. For a like reason pitch, or some form of enamel composed of bitumen and other ingredients, are found to be very valuable. Lamp- black is claimed to be a very good material for insulating pur- poses in railway and other portable refrigerating chambers, by reason of its lightness and elasticity, and more particularly on account of its non-liability to pack from jolting, and com- plete in perviousness to moisture. This material is the one employed by Henry Carr Godell, in his patent (18S4) mov- able refrigerating chamber. When it is desirable to increase the elasticity and reduce the cost, he sometimes uses a mix- ture of either short fibre or scales of mica. Whatever the filling material that may be employed for insulating purposes, however, it should always be borne in mind that the more air that is enclosed with it between the walls or skins the better, for it is a well-known fact that the best non-conductor of heat is dry air, the units of heat trans- mitted per square foot per hour, through a layer of confined air of I in. in thickness, being about '29. The following materials and dimensions have been recom- mended for walls of cold chambers : — 14 in. brick wall, 3J in. air space, 9 in. brick wall, i in. layer of cement, i in. layer of pitch, 2 in. by 3 in. studding, layer of tar paper, i in. tongued and grooved boarding, ARRANGEMENT OF ROOMS AND COLD STORES. 1 65 2 in. by 4 in. studding, i in. tongued and grooved board, layer of tar paper, and, finally, i in. tongued and grooved board- ing, the total thickness of these layers or skins being 3 ft. 3 ins. 36 in. brick wall, i in. layer of pitch, i in. sheathing, 4 in. air space, 2 in. by 4 in. studding, i in. sheathing, 3 in. layer of mineral or slag wool, 2 in. by 4 in. studding, and, finally, i in. sheathing ; total thickness, 4 ft. 7 in. 14 in. brick wall, 4 in. pitch and ashes, 4 in. brick wall, 4 in. air space, 14 in. brick wall ; total thickness, 3 ft. 4 in. 14 in. brick wall, 6 in. air space, double thickness of i in. tongued and grooved boards, with a layer of waterproof paper between them, 2 in. layer of the best quaUty hair felt, second double thickness of i in. tongued and grooved boards, with a similar layer of paper between them ; total thickness, 2 ft. 2 in. 14 in. brick wall, 8 in. layer of sawdust, double thickness of I in. tongued and grooved boards, with a layer of tarred water- proof paper between them, 2 m. layer of hair felt, second double thickness of i in. tongued and grooved boards, with a similar layer of paper between them, total thickness, 2 ft. 4^ in. See also pages 172, 177, 182, and 183 for further plans for the insulation of cold stores or chambers. The following table, from experiments by Peclet, gives the amount of heat in units transmitted per square foot per hour, through various substances, in plates or layers of i in. in thickness, many of which are suitable for insulating cold-air or refrigerating chambers. The experiments were made by heating one side of the plates or layers by means of hot water, and cooling the other side by cold water, the difference between the temperature of the two faces being 1° Fahr. The materials are arranged in consecutive order, commencing at the worst non-conductors, or best conductors of heat. Units of Units of Materials. heat trans- Materials. heat trans- mitted. mitted. Gold .... 625 Stone .... 14 Platinum 600 Glass .... 6-6 Silver . 595 Terra-cotta . 4-8 Copper 520 Brickwork . 4-8 Iron . 230 Plaster 3-8 Zinc . 225 Sand .... 2-17 Tin . 178 Oak, against the grain Lead . 113 or fibre . 17 ' Marble 24 ! 1 66 REFRIGERATING AND ICE-MAKING MACHINERY. Units of Units of ]\Iaterials. heat trans- Materials. heat trans- mitted. mitted. Walnut, with the grain Charcoal (wood) in pow- or fibre 1-4 der . •63 Fir, with the grain or Straw, chopped . •56 fibre 1-37 Coal, powder sifted •54 Guttapercha 1-37 Wood ashes ■53 India-rubber 1-36 Mahogany dust . •52 Erickdust, sifted . 1-33 Canvas, hempen new . •41 Coke, in powder . 1-29 Calico, new . •40 Iron fihngs . 1-26 Writing paper, white . •34 Cork .... I-I5 Cotton and sheep's wool •32 Chalk, in powder •86 Eiderdown . •31 ■ Blotting paper, grey . •26 The quantity of heat in units, transmitted through one square foot of plate per hour, may be found thus : subtract the temperature of the cooler side from that of the hotter side of the plate, then multiply the result by the number in the preceding table corresponding to the material used, and divide the product by the thickness of plate. Thus an iron plate 2 in. thick, having a temperature of 60° on one side and 80° on the other, will transmit 80 — 60 = 20 X 230 = 2,300 units of heat per square foot per hour." A series of five experiments t on radiation at low temperatures were conducted by Raoul Piclet on the rate of heating of a body cooled to —170° Cent. ( —338° Fahr.), the surrounding atmo- sphere being at a temperature of + 11° Cent. (+51*8° Fahr.). The refrigerators employed were cooled by a mixture of sulphur dioxide and carbon dioxide (Pictet's special liquid), or by liquid nitrous oxide, their thermal capacity being con- sidered in every case. In the first experiment the surface of the refrigerator was uncovered ; in the second it was encased in a sufficient covering of cotton waste to prevent the formation of hoar frost on the metal; whilst in the third, fourth, and fifth series protecting layers of 10, 25, and 50 centimetres in thick- ness were employed. The results showed that at extremely cold temperatures be- * Hutton. "Works Managers' Handbook." Crosby Lockwood & Son. t " Comptes Rendus de rAcademie des Sciences," Paris, vol. cxix., p. 1202 : 1894. ARRANGEMENT OF ROOMS AND COLD STORES, lb'/ tween —170° Cent. ( — 338° Fahr.) and —100° Cent. ( — 212" Fahr.) a thick layer of cotton afforded but a slight protection. It was only between the temperatures of -20° Cent. (—68^ Fahr.) and + 10° Cent. (+ 50° Fahr.) that the effect of the protecting layers became proportional to their thickness. In the opinion of Mr. Pictet, bad conductors of heat are capable of absorbing, with considerable efficiency, the radiations from bodies at temperatures between — 60° Cent. (—140° Fahr.), and -f 11° Cent. ( + 51*8° Fahr.), but are ineffective as regards calorific vibrations at temperatures below —60° Cent. ( — 140° Fahr.). With other non-conducting substances, such as silk, wool, sawdust, cork, charcoal powder, and peat, the results were identical, and, as a rule, bad conductors appeared to be freely permeable to heat at low temperatures between — 100° Cent. ( - 212° Fahr.), and —170^ Cent. ( -338° Fahr.). The table on the next page gives the results of tests* under- taken by Professor Andrew Jamieson, M.Inst.C.E., for the pur- pose of determining the relative and absolute thermal conduc- tivities of substances used as lagging for steam-boilers, for parts of steam-engines, and for refrigerating machines. The method adopted was to observe the fall of temperature in a known weight of hot water contained in a vessel coated on all sides with a certain thickness of the material under examination, the outer surface of which was maintained at a constant temperature by the continuous flow of cold water through a water-jacket. The apparatus consisted of three cylindrical tin cases, the innermost of which was fitted with a water-tight lid having central funnel through which the hot water was inserted. The space or clearance of i in. left between the first or innermost vessel, and the second vessel, contained the non-conducting material under test ; and the space between the second and third vessel formed the water-jacket. Thermometers were placed in the hot-water chamber and water-jacket, and an arrangement for stirring the water in the said hot-water chamber in the innermost vessel was likewise provided. Each specimen of non-conducting material was placed upon a separate inner case, each of the latter being covered to a uniform thickness of i in. in the manner in which the said material would be employed in actual practice. The non-conducting composition was applied in layers, carefully dried in succession, so as to ensure the dry- ness necessary to the accuracy of the tests being obtained. ■'* "Minutes of Proceedings, Institution of Civil Engineers," vol. cxxi., Session 1894-95, PP- 291, 292, 293, 294, 295. 1 68 REFRIGERATING AND ICE-MAKIXG :^rACHINERY. The covered tin cases were tested as follows : — lo lbs. of boiling water was poured through a funnel into the hot-water chamber. Cold water was then allowed to flow uniformly from the main water-pipe, and to circulate freely through the cold-water chamber. During no test was the temperature in this chamber observed to rise as much as i° Cent. The outer surface was, therefore, kept at a constant temperature through- out each test. In order to prevent the temperature of the hot water from falling too quickly at first, and to bring the non- conductor and the whole apparatus to a condition of constant temperature or heat equilibrium, steam at atmospheric pressure generated in a Florence-flask, was first passed into the inner vessel by means of a glass tube led into it through the funnel. The steam-pipe was then removed, and a paraffined cork litted tightly into its position. The first reading was always taken when the temperature of the hot water had just fallen to 94" Cent, (201 '2° Fahr.). The water in inner chamber was stirred by a perforated piston prior to the readings of the thermo- meters in the two chambers, which were taken simultaneously, being noted. Successive readings of both thermometers were taken in the same way, and recorded every ten minutes. Results of the Tests. >- "ft-—- %.3 c - 1 ^C Name of Material. iglit of Sam eluding Til fall of Tem in 120 rainu Thermal nductivity i olute Measi |l Total ture H : lbs. oz. Deg. Cent. Dry air . — 6-0 0-0000558 roo Fossil meal composition . 7 2 21-5 0-0002689 4-82 Cement with hair felt* . 5 15 30-0 0-0003613 6-47 Silicate cotton, f or slag i wool . . . ". — 29-0 0-0003875 1 6'95 Kieselguhr j composition 7 13 29-0 0-0004336 III Papier machecomposition§ / ^ 35-5 0-0004424 1 7-93 Fibrous composition (flax, 1 hemp, cow-hair, and clay) 9 9 34-5 0-0004550 7-98 j Papier machecomposition|| 8 12 37-5 0-0005019 8-99 * The outside diameter of this sample was about \ in. smaller than the inside diameter of the middle tin-case or vessel, and it had consequently a ARRANGEMENT OF ROOMS AND COLD STORES. 1 1 The results of tests 51 made by Mr. John G. Dobbie, superin- tending engineer at Calcutta to the British India Steam Navi- gation Company, to determine the conductivities of asbestos and Kieselguhr composition were as follows : — Results of Tests. Asbestos. Kieselguhr Com- position, "Water Condensed Water Condensed in Inches. in Inches. After 15 minutes . „ 45 >, • » „ 60 „ . . Totals in one hour . 4i 3l 3l 3f 2| 25 23 i4f 9| This experiment shows a saving of 36 per cent, in favour of Kieselguhr composition. The tests were made with two boiler- tubes — 3i in. in outside diameter and 7 ft. long, closed at both ends, and covered with a thickness of 2 in. of asbestos and Kieselguhr composition respectively. The tubes were sus- pended side by side, and steam was admitted at the top, a gauge-glass being fitted at the bottom of each by which the amount of condensation inside the tubes could be accurately observed. Steam at a pressure of 30 lbs. per square inch was used in the tubes. In the first trial, which lasted one hour, 12*375 in. of water were condensed in the tube covered with slight advantage over the other samples ia ha\ing a thin layer of air between its outer surface and the latter. t The sUicate cotton was pressed together tightly, and thus its conduc- i^•ity appears greater than would have been the case had it been more loosely packed. J The Kieselguhr employed consisted on the average of Silica 83-8, Magnesia 0-7, Lime o-3, Alumina i-o, Peroxide of Iron, 2*i, Organic Matter 4-5, Moisture and Loss, 7-1. It was employed in conjunction with 10 per cent, of binding material, viz., fibre and mucUaginous extract of several vegetable matters. § Papier-mache composition, consisting of paper pulp mixed with clay and carbon, together with hair and fragments of hemp rope. II A lighter modification of above. 11 " JSIinutes of Proceedings, Institution of Civil Engineers," vol. cxxi., Session 1894-5, pp. 301, 302. 170 REFRIGERATING AND ICE-!^IAKING MACHINERY. asbestos, and 8-375 i"- ^^ ^^^^^ covered with Kieselguhr com- position, showing 33 per cent, less water condensed with Kieselguhr composition. In the second trial, of one hour also, the condensation was noted every fifteen minutes, and gave the results shown in the above table. From these and other tests the author has been led to the conclusion that hard-pressed asbestos paper or cloth is a better conductor of heat than silicate cotton or slag wool, felt, hair, wool, or some of the Kieselguhr compositions. The main reason for the superior non-conductivities of porous materials is on account of the entrapped and occluded air, hence the looser asbestos and other fibrous materials are laid on the better will they prevent radiation of heat. In an appendix "'^ to his paper on heat-insulators. Professor Jamieson gives some accounts of previous experiments, of which the following is a brief extract : — " In 1881, Mr. Charles E. Emery, Ph.D., wrote a paperf on * Experiments with Non-conductors of Heat,' wherein the results of his tests on fourteen different substances are given. The apparatus used consisted of a boiler, 4 ft. in diameter and 12 ft. long, constructed with three lo-in. tubes. Into these tubes were placed smaller tubes to receive steam, and around the inner tubes were placed the non-conducting substances, water being circulated through the larger shell outside of the outer tubes. The results (see table) were shown by the amount of steam condensed in the inner tubes, the water of condensation being conducted to small cylindrical vessels, each provided with a glass gauge." In 1884, Professor John M. Ordway. of Boston, Mass., de- scribed in a paper J on " Experiments upon Non-conducting Coverings for Steam-pipes," tests of a great variety of sub- stances by three methods, viz. : (i) by measuring the tempera- tures on the outside of the coverings ; (2) by measuring the weight of steam condensed in a certain time over a certain length of covered pipe; (3) by a calorimeter. In 1884, Mr. J. J. Coleman gave§ the results of a series of * "Minutes of Proceedings, Institution of Ci^il Engineers," vol. cxxi., Sessions 1894-5, pp. 298-299. t "Transactions, American Society of Mechanical Engineers," vol. ii., 1881, p. 34. X "Transactions, American Society of Mechanical Engineers," vol. v., 1883-84, p. 73. § "Proceedings, Philosophical Society of Glasgow," vol. xv., 1883-84, p. 90. ARRANGEMENT OF ROOMS AND COLD STORES. 171 experiments (see table) on nine substances tested by means of Lavoisier's ice-calorimeter. The object of the experiments was to find the substance which would make the best covering for the " Bell-Coleman Freezing Machines." In 1884, Mr. D. K. Clark, M.Inst.C.E., reported^ to the National Smoke Abatement Institution the results of tests carried out at the works of Messrs. Samuel Hodge & Sons, Millwall, of seven substances as compared with a bare pipe. In 1891, Mr. W. Hepworth Collins read a paper f on ''The Comparative Value of Various Substances used as Non-Con- ducting Coverings for Steam Boilers and Pipes," giving the results of experiments in which a mass of each material to be experimented upon, i in. thick, was carefully prepared and placed on a perfectly flat iron plate or tray, which was then maintained at a constant temperature of 310° Fahr. The heat transmitted through each non-conducting mass was calculated in lbs. of water heated 10° Fahr. per hour (see table). Results of Different Experiments on the Heat Conduc- tivities OF Various Substances. {Silicate cottojt being taken as 100.) ! Substance. 1 1- J. J. Coleman. 1884. a § ^^ 93 100 112 III 112 Fossil meal composition Cement with hair-felt . Silicate cotton or slag wool , Hair-felt or fibrous composition Papier-mache Kieselguhr composition . Sawdust Charcoal .... Cotton wool .... Sheeps' wool Pine wood (across the grain) . Loam Gasworks breeze or coal ashes Asbestos • *83 TOO 122 132 240 229 100 117 136 163 140 122 136 230 100 114 147 142 299 179 * The Engineer, vol. Ivii., 1884, p. 65. t *' Report of the British Association for the Advancement of Science,' Cardiff, 1891, p. 780. 172 REFRIGERATING AND ICE-MAKTXG MACHINERY. As a further example of methods that have been actually successfully employed for insulation, it will be interesting to know that the cold storage chambers built at the St. Katherine Dock, London, were constructed as follows : — ! On the concrete floor of the vault, as it stood originally, a /^ covering of rough boards i^ in. in thickness were laid longi- tudinally. On this layer of boards were then placed trans- versely, bearers formed of joists 4^ in. in depth by 3 in. in width, and spaced 21 in. apart. These bearers supported the floor of the storage chamber, which consisted of 2^ in. battens tongued and grooved. The 4^- in. wide space or clearance between this floor and the layer or covering of rough boards upon the lower concrete floor was filled with well-dried wood- charcoal. The walls and roof were formed of uprights, 5^ in. by 3 in., fixed upon the floor joists or bearers, and having an outer and an inner skin attached thereto ; the former consist- ing of 2 in. boards, and the latter of two thicknesses or layers of i^ in. boards, with an intermediate layer of specially-pre- pared brown paper. The 5i in. clearance or space between the said inner and outer skins of the walls and roof was like- wise filled with wood-charcoal, carefully dried. A chill room or cold storage chamber should open into a porch, lobby, or anteroom, by which means the penetration of heat into the said chamber when it has to be entered to place provisions therein, or to remove them therefrom, is lessened. The ducts or inlets for the admission of the cold air into the store or chamber when the refrigeration is eftected by means of a cold-air machine, or by air reduced in temperature in a separate chamber as before described, are preferably placed as close to the roof or ceiHng of the room, whether land or marine, as can conveniently be done, this having been found in practice to be the most advantageous position, and the said cold air having performed its work is drawn off at outlets also situated in this position. In packing carcasses in a cold store or chamber, they should be placed as close together as possible, taking care, however, to leave a free space or clearance between them and the innei lining of the room, through which the cold air can freely circulate. When hanging frozen mutton before cooking, care must be taken that it is so placed that the juice will not run out of the cut-end- For example, hind-quarters, haunches, and legs must be invariably hung with the knuckle-end downwards; and loins ARRANGEMENT OF ROOMS AND COLD STORES. 1 73 and saddles by the flaps, so as to give thum an horizontal posi- tion. The cut-end, moreover, should always be presented to the fire first when cooking, thereby sealing it and preventing the gravy from escaping from the joint. Frozen lamb does not need any preliminary hanging, but can be cooked as soon as thawed. The proper stowage of a fruit cargo in the cold store or chamber is likewise a matter that must be carefully attended to, in order to ensure its arrival at its destination in good con- dition. The essential point to be insisted upon is that clear spaces or clearances of at least h in. be left between each tier of cases, and between the said cases and the bottom, sides, and ceiling, of the chamber. These clearances can be managed by the insertion of laths of a suitable thickness between the cases. Passages should be also provided for admitting of inspections of the state of the fruit being made during the voyage. ^he best temperature to maintain for fruit is one of from 45° to 55° Fahr., and this should be evenly kept up throughout the entire cargo. It must be borne in mind that the slightest degree of frost will destroy a whole cargo of fruit. It will gener- ally be found sufficient to run the refrigerating machine about 12 hours per day in hot latitudes and 6 hours per day in cooler ones. In a marine installation the pipe or trunk for admitting the cold air is usually fixed along one side of the cold store or cham- ber in the hold, as near the top or ceiling as possible, the return pipe or trunk being placed at the opposite side of the said chamber. As in a land installation the inlet trunk or pipe is fitted with a number of apertures governed by sliding doors ; these are only opened to a very slight extent at the end nearest the machine, and gradually more and more as they approach the end furthest therefrom, thus equalising the temperature in the chamber. The most important point is to ensure the cold air being thoroughly circulated, and penetrating every portion of the chamber, and thermometers should be hung in difi'erent positions therein to form a check to the deck pipe ones. The snow box must be cleared out repeatedly, to prevent the passages, and also the slide valve ports, from becoming blocked up, and the trunk or inlet pipe must be cleared once a day or oftener. Previous to storing the carcasses in the cold store or chamber, a thorough inspection thereof should be made, and any damage to the walls made good. When the cold store or 74 REFRIGERATING AND ICE-.MAKING MACHINERY. chamber is filled, the hatches should be made tight by caulking with oakum, or preferably they should be fitted with India- t/3 rubber insertions, which afford a greater certainty of air-tight joints being made. As regards the capacity of a machine required for the refrigeration of a cold store or chamber of any given dimen- ARRANGEMENT OF ROOMS AND COLD STORES. 1 75 sions, it would be obviously impossible, in view of the con- stantly varying circumstances of each individual case, to lay down any hard-and-fast rules. It will have to be separately estimated for each particular installation, in accordance with the amount of cooling work which is necessary, and which it is desired to perform upon the material enclosed in the cold store or chamber, and by the amount of heat that is calculated to pass into the latter from the outside, through the walls> floor j Fig. 61. and roof. It will consequently be thus seen that the capacity of the apparatus will depend upon the lowest internal, and the highest external temperature, the area of the said walls, floor, and ceiling, and also to a great extent upon their construction being carried out in a manner more or less impervious to heat. As a general rule, however, it will be found that, owing to the circulation of the air, and the radiation through the floor, walls, and roof of the chamber, the cubical contents of the air in the latter will require to be cooled from eight to fifteen times in every hour, in order to ensure the temperature being assimilated to that of the air or gas passing out of the machine. Small cold stores or chambers are now commonly used by retail butchers for the preservation of both frozen and unfrozen meat, and also by dealers in fish, poultry, and game, butter salesmen, and others. 176 REFRIGERATING AND ICE-MAKING MACHINERY. Fig. 60 is an horizontal section showing a plan of a small cold storage chamber of 1,000 cubic ft. capacity, adapted for such service. The refrigeration is effected by a Haslam cold-air machine, of 6,000 cubic ft. per hour capacity, arranged to be driven direct by means of a gas-engine, a is the gas-engine cylinder, b the air compression cylinder, and c the expansion cylinder. The air compression cyHnder B is arranged horizontally in front of, and in line with, the cylinder a of the gas motor, and the expansion cylinder c, is placed vertically, and works a disc secured upon the opposite end of the crank shaft from the fly-wheel. ARRANGEMENT OF ROOMS/ AND COLD STORES. 1 77 The advantages of a gas motor for driving the small cold-air machine required for an installation of this description are obvious, and comprise : non-increase of fire insurance premium, and ability to start the machine at any time, without having to wait to get up the necessary steam pressure in a boiler, as must be done in the case of a steam-driven cold-air machine. Fig. 61 is a perspective view, the end wall and a portion of the front wall being removed, showing a small cold store or chamber, refrigerated by means of a Puplett patent ammonia Fig. 63. compression machine, which chamber is especially designed for bacon-curers, butchers, dairym.en, fish and game dealers, &c. Chambers of this description are constructed with an outer and an inner skin, each of which is composed of two layers of i in. tongued and grooved boards, put together perfectly air-tight, and having an intervening space or clearance of about 8 in., filled with charcoal, corlc, or other good non- conducting material. The dimensions of the chambers, as usually constructed, vary from a storage capacity for frozen meat of 6 to 50 tons or more, and their daily meat-cooling capacity to 32°Fahr. runs from 20 cwt. up to 200 cwt. or more. X 178 REFRIGERATING AND ICE-MAKING MACHINERY. Fig, 62 shows a beef chill-room fitted with the De La Vergne patent pipe system, a description of which has been already given on pages 153 and 156; and Fig. 31^/ (frontispiece) illus ARRANGEMENT OF ROOMS AND COLD STORES. 1 79 trates another beef chill-room fitted up with the Haslam patent air-cooling battery. Refrigerating machines are likewise very advantageously employed in bacon-curing factories or works, for enabling mildly cured bacon to be produced in summer, by artificially reducing the temperature of the chill-rooms and curing cellars. A usual arrangement is shown in Fig. 63, which comprises rows of cast-iron flanged pipes which are fixed overhead, pre- ferably suspended from the ceiHng, over the whole area of the chill-rooms and curing cellars, and through which system of pipes brine cooled in the usual manner is circulated so as to lower the temperature of the said rooms to about 40° Fahr. By means of cocks provided on the different branch Fig. 65. mains the speed of the flow of brine through the various circulations, and consequently the temperature of the rooms, can be regulated, and reduced or increased at pleasure. In factories of moderate size the machine may usually be stopped at night and on Sundays, the cold stored up in the brine in the pipes being enough to keep the temperature of the room suffi- ciently low ; in very hot weather, and in very large establish- ments, however, the machine will have to be run continuously night and day. Both the chill or cooling-rooms and the curing- cellars are l8o REFRIGERATING AND ICE-^IAKING MACHINERY. fitted up in practically the same manner; the v/ork in the chill or cooling-rooms where the hot meat is cooled down is much greater in proportion to their size, however, and is moreover intermittent, consequently a proportionately larger number of brine pipes are placed therein, and the brine is turned on or off as the rooms are full or empty ; on the other hand the work in the curing- cellars is less and regular, and, there- fore, a much smaller number of brine pipes are required, the circulation of brine being kept up all the time the machine is running, and a perfectly steady and even temperature main- tained. Fig. 64 illustrates a hog chill-room, fitted with the De La Vergne patented system of pipes, working with direct expansion of the ammonia gas or vapour (see pages 153, 156). The reason that artificial refrigera- tion is now imperatively required in bacon-curing works is on account of the demand that has arisen for mild- cured bacon. Formerly the pigs, after being killed, were cooled simply by exposure to the atmospheric air, being subsequently cured in underground cellars at the temperature of the earth or from 52° to 55° Fahr. In order to prevent the rapid decomposition, and consequent taint of the bacon which would otherwise inevitably occur at these comparatively high temperatures, the latter was charged with an excessive amount of salt as a preventative. This excessive salting was indispensable in summer especi- ally^ when, indeed, curing was almost prevented, although bacon at that season is in the greatest demand, and the highest prices are obtainable. The modern requirement, however, for more, and more mildly-cured bacon has rendered absolutely necessary an artificial reduction of the temperature of the chill-rooms and curing-cellars. to ARRANGEMENT OF ROOMS AND COLD STORES. l8l The first attempts in this direction were made by constructing the cellars with iron ceiHngs, on the tops of which were stored vast quantities of ice, a system which is found to be suiiiciently effective, but is very expensive, not only by reason of the first cost of the iron ceilings and the necessary supports, but also by reason of the space occupied by the said ceilings and ice chambers, and furthermore on account of the large outlay Fig. 67. entailed lor the ice itself, and the labour of handling it. There is, besides this, the risk of the supply of ice running short in the hot weather, with, of course, disastrous results. An arrangement of a small cold store or chamber, such as is very frequently constructed on board a large passenger steamer, is shown in sectional plan in Fig. 65. The refrigera- tion is effected by means of a Lightfoot, Haslam, or other cold-air machine of the vertical type. The arrangement of this cold store or chamber, which is Fig. 68. practically similar to that of those used on the passenger steamers of the Peninsular and Oriental Company, will be very readily understood from the drawing, wherein a is the meat room, the temperature of which is kept down to about 20° Fahr., and wherein are situated the ice-making or freezing tank B, the ice cans or cases b^ b^, and the ice store c. D is the vegetable room, which is maintained at a tempera- ture of about 40^^ Fahr., and in which are placed the water- cooler E, wine closet or cooler f, and hanging room G. >( 1 82 REFRIGERATING AND ICE-MAKING MACHINERY. The cold air provision stores or chambers on board of the Cunard Company's steamships Ca7npa7iia and Liicania are fitted up with refrigerating plants, on the De La Vergne ammonia compression system. The refrigeration is effected on the brine circulation, and not upon the direct expansion system, a solution of calcium chloride being the agent or medium employed, and the said solution is reduced to a very low temperature in the usual mEnner, by the expansion of the ammonia gas or vapour, in coils or pipes submerged therein, and is circulated by a special pump through the system of cooling or refrigerating pipes, which latter are fixed to the underside of the roof or ceiling of ) the cold store or chamber. The method employed for the insulation of the store or chamber is shown in Figs, dd and 67, which are vertical sections through the roof or ceiling thereof. A, A, are the refrigerating pipes; b, b, the meat rails; c is a filling of sawdust; D, d, are layers or skins of tongued and grooved boarding ; e is a layer of hair felt ; and f, f, are layers of tarred water-proof paper. The brine pipes are divided into two sections or sets, thereby admitting of any necessary repairs being effected in one section, without in any way interfering with the circulation of the cold brine through the other section, and special means are also provided for withdrawing the brine from one set or section without interfering with the working of the other. The ammonia compressor is of the vertical single-acting type, and is actuated by a high-pressure horizontal steam-engine. The compressor cylinder is 4J in. in diameter, by 9 in. stroke, and the steam-engine is of 2^ horse-power, and is fitted with a special governing arrangement, by means of which the steam supply is determined, the speed being capable of variation within a wide range (say between 30 to 300 revolutions) with- out interfering with the running of the machine. The con- struction of the compressor is substantially similar to that described with reference to Fig. 15, and the oil separator and other parts only differ from the arrangement shown in the general view of a complete installation shown in Fig. t6, in that the ammonia compressor is of the single-acting type, and by reason of the smaller capacity of the present plant, and the absolute necessity on shipboard for economising every cubic inch of room possible. The operation of the appa- ratus is, however, in every way identical, and the description of the said complete installation will apply equally well in this case. ARRANGEMENT OF ROOMS AND COLD STORES. 1 83 The apparatus is capable of making 5 cwt. of ice daily, in addition to the performance of the refrigeration required in the cold store or chamber. The cargo holds of the same steamships are refrigerated with machines of the Kilbourn type. The meat-carrying chambers in each of these vessels consists of three chambers situated for- ward on the orlop or lower deck, and having a total capacity of 20,000 cubic ft., which renders them able to carry 2,700 quarters of beef. The chambers are very carefully insulated, ^C the walls consisting, as shown in Fig. 68, first of a double thickness of tongued and grooved boards a, a, having a layer of waterproofed paper B between them, next a 2-in. layer of good quality hair felt c and another double thickness of tongued and grooved boards D, d, with a similar layer of paper e between ; them, and finally an inch air space F between the latter and j the inner or iron deck, the whole being well varnished. The j _ brine cooling pipes, which are of heavy 2-in. galvanised tube with malleable cast return bends, are placed on the ceiling be- tween the deck beams, thus economising head room, and the rails for the meat-hooks are of i^ in. galvanised round iron, firmly clipped to the beams supporting the decks. The meat hooks which are placed upon the latter, for carrying the quarters of beef, are of steel galvanised. Thermometer tubes from the upper deck are provided to each chamber, so that the tempera- ture may be ascertained in any part of the said chamber, when desired. Fig. 69 is a plan showing the general arrangement of the machine-room. A pair of compressors are employed, a, a, are the steam-engine cylinders ; b, b, the compression cylinders ; c, c, the ammonia condensers ; d, d, the liquid ammonia reservoirs ; e, e, the refrigerators ; F is a brine circulating pump of the duplex pattern; g a manifold or distributing pipe to the different cooling pipes in the chambers ; h is the collecting pipe at the top of the refrigerator. It will be seen that the cold parts of the machine are enclosed in a separate chamber having walls insulated in a similar manner to those of the meat-carrying stores or chambers, thereby preventing as far as practicable loss through absorption of heat. The compressors are similar in construction to those already described with reference to Fig. 27, and are of an ice-producing capacity of 12 tons a day, the compression cylinders being 6 in. in diameter by 12 in. stroke, and the steam cylinders 8 in. diameter by 12 in. stroke. 1 84 REFRIGERATING AND ICE-MAKING ^lACHINERY. The ammonia condensers c are constructed of a cylindrical form, the shells being made of wrought-iron, and the covers of cast-iron, and they are fitted with concentric coils of li in. galvanised n-on pipe, connected together at their extremities by means of tee pieces made of malleable castings. The said ammonia condensers, moreover, are carefully lagged with teak wood. The water for use in the ammonia condensers cis sup- plied and circulated by means of a duplex steam pump (not shown in the drawing), located in the forward boiler-room of ARRANGEMENT OF ROOMS AND COLD STORES. 1 85 the steamship. The ammonia gas after compression in the com- pressors B, and h"quefaction in the condensers c, under the combined pressure of the said pumps or compressors b, and the cooling action of the condensing water circulating on the ex- terior of the coils or worms in the condensers, is delivered to the reservoirs d for the liquefied ammonia, through small bore pipes. From these reservoirs the said liquid ammonia is admitted through suitable graduated expansion or regulating valves to the lower ends of the expansion coils in the refriger- ators E, wherein the liquid ammonia again vaporises or gasifies, abstracting the heat required for this process from the brine surrounding the expansion coils, and being again returned to the compressors, and so on ad infinitum in the manner already described. The absolute working pressure in the refrigerators is about 30 lbs. per square inch. The brine having been reduced to the desired temperature in the refrigerators, passes into the system of brine circulating pipes, and maintains the atmosphere of the cold stores or chambers at a temperature suitable for the proper preservation of the meat. The circulation of the brine is efi'ected by the brine pump f, which draws the cooled brine from the bottom of the refrigerators e, and discharges it through the dis- tributing tee-piece and valves, or manifold g, to the different sections of the cooling pipes in the chambers, and returns it through a similar tee-piece, manifold or distributor h, to the top of the refrigerator to be again cooled. The return brine pipes are each fitted with a regulating valve and a thermometer. An important type of portable refrigerator is that adapted to meet the requirements of barges, railway trucks, and cars or vans, which it is desirable to maintain at a low temperature for considerable periods, but which, for obvious reasons, it is undesirable, in doing so, to encumber with machinery, to in- crease in weight to any considerable extent, or to render in any way necessary the employment of special labour to take charge of same. The frozen meat, as a rule, arrives in good condition on board the vessels, and deterioration in quahty usually takes place during its transference to the cold stores on land, and again during the subsequent delivery thereof to the retailer, when the said meat is exposed to temperatures frequently much higher than what is required to preserve it in good condition. The great desideratum for this purpose is a plan which will 1 86 REFRIGERATING AND ICE-MAKING MACHINERY. avoid the necessity of carrying the source of refrigeration upon the conveyance itself, which necessity has hitherto rendered the latter too expensive for practical purposes ; this the Pulsometer Engineering Company, Limited, claim to have successfully accomplished in their system of refrigeration for barges, railway trucks or cars, and other portable chambers, and they state that they are willing to guarantee to maintain below the freezing point properly fitted portable chambers of all kinds, for ample time for transit between Penzance and Aberdeen. Since the beginning of 1888, moreover, the London and Tilbury Lighterage Company, Limited, have had barges fitted with special refrigerating apparatus successfully plying upon the Thames, the meat landed by them being invariably in good condition, and not infrequently at a lower temperature then, than when first discharged from the vessel. The method of refrigeration primarily employed in vans and railway trucks, was to effect the production of cold with mixtures of ice and salt. The great objection to this arrangement is the large increment of weight, and the nuisance and damage caused by the moisture due to the melting ice. As early as the year 1867 a refrigerator car was constructed in the United States having a refrigerating chamber surrounded by an air space. A fan or blower was provided, driven off one of the car axles, and air was forced by this blower througli a compartment containing ice into the refrigerating chamber. The water resulting from the liquefaction of the ice in the said compartment, which had a capacity of about 2 tons, was drawn off through a suita^Dle trap. In some instances the ice was replaced by a refrigerating mixture passing through a suitable pipe in the ice-box or chamber. The air was drawn in by the fan during the forward motion of the car, and after being passed through the ice-chamber was delivered at the top of the refrigerating chamber. A car of this description is said to have successfully transported meat slau::;htered in Illinois to New York, during the hottest part of the summer, no perceptible deterioration in quality having occurred during the ten days' journey. Another refrigerator car of somewhat similar construction, having the external appearance of an ordinary freight car, has an ice-box at each extremity wherein the ice is placed upon gratings so arranged that a current of cold air circulates con- tinually through a flue situated near the top of the chamber, over the surface of the ice, down to the floor, and tlien up ARRANGEMENT OF ROOMS AND COLD STORES. I«7 again amongst the meat. The air circulation is maintained by a fan in a like manner to that above-mentioned. The car was also built double, with inside double doors, filled in with char- coal, and the temperature of the meat was easily kept at about 40° Fahr. even in the hottest weather. As has been already mentioned Godell uses lampblack, or a mixture of lampblack and mica scales, as non-conducting ma- terial for use in refrigerator cars. In another arrangement, also used in America, the car is cooled by means of some suitable volatile liquid, which is allowed to vaporise slowly through a system of pipes from one reservoir into another, thus reducing the temperature of the chamber. The objection to this arrangement is the danger of leakage of the said volatile liquid taking place into the refrig- erating chamber. CHAPTER XL Various other Manufacturing and Industrial Applications. Uses are now made of refrigeration in many manufactures and industries, besides that of its more legitimate and impor- tant application to the preservation of various provisions of a perishable nature, which latter has been already dealt with, so far as space would allow, in the preceding chapter. All the systems hereinbefore described, with the exception of the first or that wherein the abstraction of heat is effected by the more or less rapid dissolution or liquefaction of a solid, are, to a greater or less degree, advantageously applicable for this purpose. Although the preservation of organic substances was the first known and the most obvious use, the successful application of artificial refrigeration to a process of manufacture is somewhat older than that to the preservation of provisions, a Harrison ether machine having been erected at Trueman, Hanbury tS: Co.'s brewery about 1856, which machine was stated, at a meeting of the Institution of Mechanical Engineers, held in 1 886,''' to be still at work and acting efficiently. A machine of the same type was also said to have been put up by A. C. Kirk in i86i,f who employed it for the extraction of solid paraflin from shale oil. The application of a refrigerating machine to the cooling of chocolate during the process of manufacture was first made by J. S. Fry in 1882, J in which year he employed one of Lightfoot's double expansion horizontal cold-air machines, and was enabled to proceed without interruption throughout the whole year with work that had previously to be suspended during the hot * "Proceedings, Institution of Mechanical Engineers," 1S86, p. 2^6. t Ibid., p. 231. X Ibid.y p. 236. INDUSTRIAL APPLICATIONS. 1 89 weather. Since that time tlie use of refrigerating machines in chocolate works has becon:ie ahiiost universal. One of the, if not the, most important of the other indus- trial applications of refrigerating machines is that of cooling water to be used for refrigerating and attemperating purposes in breweries. This is more especially required when the supply of water is derived from a river or other source exposed to the heat of the sun, or from the water mains in large towns, the water from both of these sources usually rising, during the summer months, to from 65° to 70° Fahr. Where a plentiful supply of well water at a temperature of from 50° to 54° Fahr. can be obtained, the provision of means for artificial cooling become of minor importance for this special purpose, and can be dispensed with. When, however, the water supply is at a comparatively high temperature, such as that above indicated, it would of course be totally impossible to cool the worts down to the ordinary pitching temperatures of from 57° to 59° Fahr., or to control the fermentation in the tuns or squares with water at such a tem- perature passing through the attemperators, and, moreover, on the completion of the fermentations it would be likewise quite impracticable to cool the finished beers down to the tem- perature desiiable for racking. In Fig. 70 is shown the arrangement of an apparatus for cooling water for refrigerating and attemperating purposes in a brewery, by means of an ammonia absorption machine of the Pontifex-Wood type. In the illustration h is the water-service pipe from the company's main, or from other source of supply ; i is the cooJed water-pipe leading from the cooler d up to the ice-water tank J, in which the cooled or refrigerated water is stored to be drawn off as may be required for refrigerating or attemperating. A thermometer is fitted on the pipe i at the outlet from the cooler, and a regulating cock or valve on the pipe h, by which the supply can be so adjusted as to admit of the cooled water being deHvered at any predetermined temperature. The water from the supply pipe h is run direct through the coil of the cooler d of the machine (which is placed on the ground floor of the brewery, and sufficiently near the steam boilers to admit of a supply of steam being obtained for use in the generator), from whence it passes reduced to a temperature of 45° or 50° Fahr., or to any other desired lower temperature, to the tank j, which is at a sufficient elevation to command the refrigerators and Fig. 70. INDUSTRIAL APPLICATIONS. IQI attemperators, and from which, as above-mentior.ed, it can be drawn off as wanted. The tank j is fitted with a suitable Ud or cover, and is preferably constructed of wood, or of iron lagged with wood and sawdust. A full description of the Pontifex-Wood ammonia absorption machine, having reference to the letters upon the drawing (Fig. 70), will be found on page 108. In working an arrangement of this description the machine is started in the morning sufficiently early to admit of the ice water tank J being filled up by the time the refrigerators are set to work. The machine is kept in operation until the refrigerating is done, and for a sufficient length of time after to admit of the tank J being filled up again, so as to provide a sufficient supply of ice water for the use of the attemperators during the night and until the machine is again started next day. It is stated by the makers that when the tank j is properly constructed as regards insulation, it has been constantly found in practice that ^he rise in temperature of the water is not more than 1° Fahr. during a stoppage of from twelve to twenty-four hours. The ice water from the tank j is forced through the attemperators, due provision being made for enabling the supply to each of them being suitably regulated, or cut off altogether if desired, independently of the others. The pump for circu- lating the ice water through the attemperators should be self- acting, and provided with an automatic regulating device, thereby enabling it to act efficiently whether one or all the attemperators be at work. The results obtained by the use of this arrangement in a brewery are, in addition to a marked improvement in the quahty of the beer, that there is a complete control over the refrigeration and fermentation, the beer refrigeration can be performed in a very much shorter time, and, consequently, the day's work completed sooner, and lastly, that the waste occa- sioned by the necessity for passing the greatest possible quan- tity of the comparatively hot water through the refrigerators and attemperators is obviated. This latter item alone is by no means insignificant, the saving where water companies' water is employed for refrigerating and attemperating being generally more than half. In large breweries where several machines are employed, they are kept running continuously day and night. An ordinary refrigerator for cooling hot beer wort consists Df a shallow vat wherein is mounted a continuous tube or pipe, through which the, cooling water is forced in a direction 192 REFRIGERATING AND ICE-MAKING MACHINERY. opposite to that taken by the said wort. The object oi thus running the wort in one direction and the water in another is to insure the dehvery end of the wort being exposed to the coldest portion of the stream of water. In another form the wort passes through a coil of pipe arranged in a vat, through which a circulation of cooling water is kept up. A more complicated arrangement is thatwherein boxes are arranged to project alter- nately from opposite sides of a double walled vertical case ; through the latter and which boxes the wort is caused to take a zigzag course by suitable check-plates extending centrally into the said boxes. The cooling water takes a like sinuous or zigzag course on the exterior of the said boxes. A wort or beer- cooler, employed in many large breweries, is a large shallow, covered vat, fitted with a volute formed by a wide strip of metal set on edge between the upper and lower plates or heads, to which it is attached, in such a manner as to form a helix with two distinct spaces. Through one of these spaces the refrigerat- ing liquid, or medium, is circulated, suitable inlet and outlet passages being provided, and through the other the wort or beer to be cooled. Brotherhood's refrigerator consists of a number of long boxes placed side by side or otherwise, each box having a flow and return passage for the cooling water, and copper tubes through which the wort passes. Hollow covers at the ends of the boxes afford communication between one tier of tubes and another. IMash tuns are likewise constructed in which the vertical shaft carrying the rake or stirrer is formed hollow, as also the arms of the said rake, which latter are perforated with a number of small holes. Through the above-mentioned hollow shaft and perforated arms steam is first passed to boil the wort, and subsequently air, reduced to a low temperature in order to cool or refrigerate it. In a refrigerating or cooling apparatus on a somewhat similar principle, air, previously reduced to a low temperature, is forced into the perforated false bottom of a vat, from whence it escapes, through the said holes or perforations, and passes up through the wort or beer contained therein. Numerous other arrangements are also in use in this country and abroad. Two of which, of American origin, are as fol- lows: — In the first the hot wort is delivered into a trough of a V shape in transverse section, from the bottom of which it trickles over a series of horizontal pipes arranged in line vertically, and through which the cooling water is passed, the cooled wort being finally collected in an U-shaped trough for delivery to the fermenting tun. INDUSTRIAL APPLICATIONS. 1 93 The second, which is extensively used in America for cool- ing or refrigerating hot beer wort, is that known as the *' Baiidelot Cooler." This apparatus is constructed for use both with a brine circulation and direct expansion. In the first case, the upper portion, or half of a set of tubes or coils, arranged horizontally, is cooled by the ordinary well or main water, and the lower part or half thereof by a circulation of cold brine or ice water. In the second arrangement the upper part or half of the said pipes or coils is similarly cooled, but the lower portion or half is cooled by direct expansion of the gas or vapour. The ordinary practice is to first slightly reduce the tempera- ture of the hot wort by exposing it in the large tank known as the cool-bed or cool-ship, which is generally located on the top of a building and roofed over, the sides being only enclosed by lattice work, so as to allow a free circulation of air, and then permit it to flow slowly down over the tubes or coils of the "-Baudelot Cooler." The Pontifex-Wood brine refrigerator (Fig. 74), a description of which will be found on page 201, with reference to its application to the cooling of water for use in margarine factories, is also very successfully employed for cooling beer worts. Another, and also a very important, use for a refrigerating machine in breweries is that of cooling the air in the fer- menting and yeast rooms, an arrangement for which purpose, on the brine circulation systems, is shown in Fig. 71. This cooling is necessary during hot weather, even in cases where an unlimited supply of cold water for refrigerating and attemperating is obtainable, inasmuch as the water can only be applied to the cooling of the beer itself in the fermenting vessels, and not to the head of yeast above. The result of this is that, although the fermenting beers can be kept well under control by the use of the attemperators, the yeast above is frequently found to be going wrong by reason of the ex- cessive temperature of the atmosphere of the room. In employing a refrigerating machine for this purpose, in connection with the arrangement shown in Fig. 71, brine re- duced in the cooler or refrigerator to about its own tempera- ture, that is from 10° to 20° Fahr., or very much lower if desired, is circulated through rows of pipes b fixed over the tuns A, or the squares, to be cooled in the fermenting rooms^ and also in the yeast rooms, the said system of pipes being 194 REFRIGERATING AND ICE-MAKING MACHINERY. reduced by the brine to below freezing point, and the atmos- phere of the rooms from contact with the latter to 45° or 50^ Fahr., or any other desired point. By this means an October temperature, that is to say, one of 50° Fahr. or less, can be obtained during the hottest summer weather. INDUSTRIAL APPLICATIONS. 195 Fig. 72 shows an arrangement for cooling a fermenting room on the direct expansion principle, fitted with the De la Vergne patented pipe system, a detailed description of which will be found on pages 153, 155 and 156. The speed of the flow of brine through the various circulations (Fig. 71) can be regulated at will by means ot stopcocks or valves provided on the several branch mains, and that of the gas or vapour (Fig. 72) by the expansion valve, and consequently, also the temperature of the fermenting rooms. In simple igC) REFRIGERATING AND ICE-MAKING MACHINERY arrangements, such as that illustrated in Fig. 71 and Fig. 72, the brine mains b (Fig. 71), and the direct expansion pipes (Fig. 72), cool the entire area of the fermenting room, that is to say, a separate brine circulation (Fig. 71) or coil of vapour pipes (Fig. -72)' is run over each row of rounds or tuns, and all are cooled at once. Where a number of large squares have to be cooled, however, a more elaborate arrangement is preferably employed, and the sides and tops of the squares are boxed in or enclosed with partitions formed of light boarding, under which a separate circulation of brine or vapour pipes to each square is fixed. The latter plan enables the temperature of the air over each square to be regulated separately and indepen- dently of the others, and the brine or vapour to be shut oft completely from empty squares, thereby lessening the work of the refrigerating machine. It also further economises the work of the latter, inasmuch as only the air directly over each vessel has to be cooled. In working a refrigerating machine on the brine circulation principle, for these cooling purposes, in a brewery of moderate dimensions, it is usually run during the daytime, and when it is shut off at night, and the fermenting rooms are closed up, the large amount of cold stored up in the brine in the pipes over the fermenting vessels, is, as a rule, found to be sufficient to keep the atmosphere of the rooms down to the desired tem- perature during the night; except, however, in very hot weather, when the machine has usually to be run continuously. In very large breweries also it has generally to be kept working day and night. In some instances, a refrigerating machine is employed for the combined purposes of cooling water for use in refrigerating and attemperating, and of cooling the air in the fermenting and yeast rooms. In an arrangement of this description, at the top of the brewery building, or at a sufficient elevation to com- mand the refrigerators and attemperators, is fixed a suitable ice-water tank, and above this tank a brine refrigerator, which latter may consist of horizontal rows of brass or copper pipes, through which a branch circulation of cold brine from the mains is run, whilst over them the supply water at 60° or 65° Fahr. or other temperature, is allowed to trickle or flow slowly. This water is thus reduced by the cold brine within •the pipes to about ;^;^'^ Fahr., or to any other desired tempera- ture, after which it is passed into the ice or cold water tank, from which it is drawn through pipes as required for refriger- INDUSTRIAL APPLICATIONS. 197 ating and attemperating. This arrangement admits, by the simple opening, closing, or regulating of the stop-cocks or valves, of the whole or any desired proportion of the power of the machine being applied to the cooling of air, or to the cooling of water, or to both operations at the same time. Lager beer fermenting rooms, and store cellars, can be cooled by a plan substantially similar to that shown in Fig. 71, for cooling the air in fermenting and yeast rooms in ordinary breweries. In the case of lager beer, however, where the whole of the fermenting rooms are kept at a temperature of about 42° Fahr., and the stores at about 38° Fahr., a propor- tionately larger number of brine cooling pipes are required. Another obvious application of refrigerating machines in breweries, though one of secondary importance, is that of making small quantities of ice, either for use in keeping yeast cool, or to send out to public-houses, or for private use. This can be very easily accomplished with machines having a brine -x:irculation. If only opaque ice be required, all that is neces- sary is to place galvanised iron pails, moulds, or cans of the shape of which the blocks of ice are desired, and filled with water, in the brine tank, and the said water will be frozen in a {qw hours into solid blocks of ice, which can then be loosened by dipping in warm water, and turned out of the said cans, the latter having a slight taper, to admit of this being more readily performed. When, however, clear, transparent crystal ice is desired, it is necessary to use de-serated water, or to keep the water in motion whilst freezing, and some special appara- tus is consequently required, such as will be found described in the chapter on ice-making. Further important applications of refrigerating machinery to manufacturing purposes are : — In candle works, for the extrac- tion of the solid stearine and paraffin. And in paraffin oil works, for enabling refiners to extract in an economical manner in the presses a greater quantity of paraffin than is obtainable in any other manner, and also to obtain a product of a superior quality. An ordinary arrangement for the extraction of solid paraffin from shale oil is shown in Fig. 73, wherein a a are the cooling drums or cylinders, b b the troughs or receptacles intended to contain the oil to be treated, and c c scrapers for removing the partly solidified oil from the drums or cylinders a. The operation of the apparatus is exceedingly simple, a circulation of brine, first reduced to about iq^ or 12° Fahr. 198 REFRIGERATING AND ICE-MAKING MACHINERY, or other desired temperature, in the usual manner, is afterwards tJC passed through the set of coohng drums or cylinders a, entering each of the latter at one of the hollow trunnions or INDUSTRIAL APPLICATIONS. 1 99 gudgeons, and leaving at the other. The lower portions of the drums or cylinders a project, as shown in the drawing, into the open shallow troughs b, one of which is placed below each drum, and in which the oil to be cooled and treated is placed. The surfaces of the drums or cylinders a during their revolutions dip into this oil, and become coated with a thin film of it, which is cooled by the circulation of the cold brine from the machine, and reduced in temperature during the continuance of the revolution, until it is finally re- moved in a pasty condition by the scrapers c, one of which is arranged to press against the periphery of each of the said drums or cylinders. The remaining oil is then drawn away by plunger pumps, and forced through filter presses, which separ- ate the paraffin wax crystals or scales from the oil. The employment of a refrigerating machine of one type or another in a works engaged in the production of paraffin is, and indeed has been for some years past, deemed indispen- sable, and but few manufacturers now endeavour to do without it. Indeed, the development of the industry dates from the time when an ether machine of the Harrison type was first used for this purpose, which, as already mentioned, was in 1861.^^ In manufactories of artificial butter, as also in other butter and cheese factories and dairies, but more especially in the former, refrigerating machines play an important part, both for ensuring an ample supply of cold water, and for cooling stores or chambers, the former being an essential for successful manu- facture in hot weather, and the latter enabling butter and margarine to be kept in prime condition until a favourable opportunity for disposing of it presents itself. In the manufacture of artificial butter a variety of ingredients are first melted and amalgamated together at about blood heat in churns, and the resultant mass is then mixed with and run out into ice-cold water contained in open troughs. This sudden application of intense cold crystallises and granulates the artificial butter, which is then skimmed off, and at the same time it also washes out the butter milk, which otherwise, by its rapid decomposition, would taint the butter. Primarily, and indeed slill to a considerable extent, the means adopted for reducing this water to the requisite temperature is * For further information regarding the most recent and approved practice in paraffin cooling, see "Journal of the Society of Chemical iuJustry," cf 29th May, and 30th November, 1885. INDUSTRIAL APPLICATIONS 201 the application of natural ice, which is placed in tanks partially filled with water, and by melting imparts its cold to the latter. This plan, however, is open to several serious objections, amongst which may be mentioned : — The excessive cost of the ice and of the necessary labour for handling it ; the impossibility of thus obtaining as low a temperature as is desirable, the best result being the mean of the two temperatures of the ice and the water ; the non-attainment of a regular temperature continu- ously ; and finally that the natural ice is always more or less dirty, and renders the cooled water so also, and consequently soils and spoils the colour and appearance of the artificial butter. Figs. 74 and 75 illustrate an installation of an ammonia absorption refrigerating machine in an artificial butter factory, and Fig. 76 that of an ammonia compression refrigerating machine in a dairy. In the first of these arrangements (Fig. 74) an ammonia absorption machine of the Pontifex-Wood type is employed. The operation is very simple, a circulation of brine is forced by the brine pump h first through the coils of the cooler d wherein the expansion of the ammonia gas cools it down to about 20° Fahr., and secondly through the pipe i to the bottom of the refrigerator l, the construction of which latter is more clearly shown in the enlarged view thereof, Fig. 75. It consists of sets or rows of horizontally arranged copper or brass tubes, secured at their extremities in return heads, and through which the cold brine from the cooler D passes. Over these tubes the supply water is allowed to trickle into the cooled or ice-water tank m, from which it is drawn off as required for the use of the churns through the pipes n. In this manner a steady and constant supply of clean cooling water at a temperature as low as 32^-° Fahr. is ensured. The brine reiurns to the pump h from the top of the refrigerator l through the pipe j. In factories where the practice of using water cooled down only to 39° or 40° Fahr. prevails, the brine refrigerator l can be dispensed with, and the water to be cooled may be simply run through the pipes in the cooler D as in the arrangement in a brewery for cooling water for refrigerating and attempera- ting, shown in Fig. 70. A full description of the Pontifex-Wood ammonia absorption machine, reference being made to the letters on Fig. 74, will be found on page 108. 202 REFRIGERATING AND ICE-MAKIXG MACHINERY. 1 ... W^ T'W^ =^ ■^w ^ 1 <~ ' i M^ W\ 1 H < < 1 1 m < < < < ' ' ' ' 1 m 1 '■ < < =^' < Ij ^^ 5 i — < 1 s^s < ^s <' i " |! ^^ <: 1 < <; - < ~ < k. .1 : k < ^s^ < - < < ^^ < ^si < < % 1 M ^1 i*T]Ae^^; with the tempera- ture of the brine. ^ ' -', " -^ -rli-w^- T-- - ': '^^ ■ ; - The cost of making a ton of opaque and porous ice with a vacuum machine such as the Windhausen is estimated * by Dr* Hopkinson at 4s. The amount of water required (including that used for cooling purposes) is stated f by Mr. Pieper to be from 10 to 12 tons per ton of ice produced, and the fuel consumption i ton of coal for every 12 tons of ice. The fuel is required for the generation of steam to drive the vacuum pump, and the air pump, of the concentrator. The total heat which niust be abstracted to produce a ton of ice from a ton of water at a temperature ;Of6Q'° Fahr* is 382, 144 units. The Windhausen machine; is heavy, an 212° -37-3° 96^ -10-5 14° -2-2° sure . . . ) Latent heat ofvapor- i isation at atmos- | pheric pressure . ) 966 900 165 473 182 — Fahr. lbs. lbs. lbs. lbs. lbs. lbs. is - 40' - 20° 19-4 — 12-0 5-7 II-6 o° — 30-0 1-5 i8-7 9-« 15-4 2 ^ C o + 20° — 47"7 2-6 28-1 16-9 22-0 11 + 32° 0-089 6i-5 3-6 36-0 22-7 27-0 + 40° 0-122 73-0 4-5 42-5 27-3 31-3 1 r^ + 60° 0-254 io8-o 7-2 61-0 41-4 44-0 1 §^ + 80^ 0-503 152-4 10-9 86-1 60-2 60-0 1 N 100° 0-942 210-6 i6-2 118-0 «4-5 79-1 >B 120° 1-685 283-7 23-5 — 117-5 99-7 ^ p . 140" 2-879 33-5 — — Absolu r squai ratures 160^ 4-731 — 45-6 — ■ — • — 180^ 200° 7-511 11-526 — 62-0 8i-8 — — _ (D 0) 212° 14-7 — 96-0 — — — USEFUL TABLES AMD MEMORANDA. 241 Table giving weights of aqueous vapour held in suspension by 100 lbs. of pure dry air when saturated, at different tem- peratures, and under the ordinary atmospheric pressure of 29*9 in. of mercury. — Box and Lightfoot. Temper- Weight of Temper- Weight of ature. vapour. ature. vapour. Fahr. Fahr. 1 degs. lbs. degs. lbs. — 20 0-0350 102 4-547 -10 0-0574 112 6-253 0-0918 122 8-584 + 10 O-1418 132 II-771 20 0-2265 142 16-170 32 0'379 152 22-465 42 0-561 162 31713 52 0-819 172 46-338 62 I-I79 182 7 1 "300 72 I -680 192 122-643 89 2-361 202 280-230 92 3-289 212 Infinite N.B. — The weight in lbs. of the vapour mixed with 1 00 lbs. of pure air at any given temperature and pressure is given by the formula 62-3 E 29-9 — ] X 29'9 P Where E = elastic force of the vapour at the given tempeia- ture, in inches of mercury (to be taken from Tables) p = absolute pressure in inches of mercury = 29*9 for ordinary atmospheric prcssur . 242 REFRIGERATING AND ICE-MAKING MACHINERY. Properties of Saturated Ammonia Gas. — Ya>yan. Tempera- Pressure from Heat of Volume of Volume of Gauge ture Fahr. vacuum in lbs. per sq. in. vaporization. vapour per lb. cubic ft. liquid per lb. cubic ft. pressure per sq. in. -iO io-6g 579-67 24-38 •0234 ""'o'-'"'] -35 i2-3r 576-69 21-21 -0236 o- -30 14-13 573-69 18-67 •0237 o- -25 16-17 570-68 16-42 •0238 147 -20 18-45 567-67 14-48 -0240 3-75 i -15 20-99 564-64 I2-8I •0242 6-29 : -10 2377 561-61 11-36 -0243 9-07 ! - 5 2757 558-56 9-89 •0244 12-87 ! 30-37 555-5 Q-I4 •0246 15-67 I + 5 34-17 552-43 8-04 •0247 19-47 i + 10 38-55 549-35 7-20 •0249 23-85 + 15 42-93 546-26 6-46 -0250 28-23 + 20 47-95 543-15 5-82 •0252 3325 + 25 53-43 54003 5-24 •0253 38-73 + 30 59-41 536-92 4-73 •025^ 44-71 + 35 65-93 533-78 4-28 -0256 51-23 1 + 40 73-00 530-63 3-88 -02=57 58-30 + 45 80-66 527-47 3-53 -0260 65-96 + 50 88-96 524-30 3-21 -02601 74-26 ! + 55 97-63 521-12 2-93 •02603 82-93 460 107 60 517-93 2-67 •026:^ 92-90 ■ +^S '118-03 . 515-3^ 2-45 *0266 103-33 + 70 129-21 ' 511*52 2-24 •0268 "4-51 ■~' +75 ^ - 141-25 - 508-29 2-05 -0270 126-55 + 80 ^54-11 50466 1-89 •0272 . I39-4J + 85 167-86 501-81 i-,74 •0273 153-16 + QO 182-8 498-1 r. i-^i. 0-274 168-10 1 + 95 198-37 49529 1-48 0-277 183-67 1 + LOG 215-14 ■ ■ ■ T 491-50 1-36 0-279 200-44 To CONVERT DEGREES CENTIGRADE OR ReAUMUR INTO DEGREES Fahrenheit. Let F = degrees Fahrenheit ; C = degrees Centigrade ; and R = degrees Reaumur. 9 R F = -^— + 32 4 ^ ^ C 5 (F - 32) 9 R =: 4 (F - 32) USEFUL TABLES AND l^IEMORANDA. 243 Comparison between the Scales of Centigrade and Fahrenheit Thermomrtkrs. -- - , Centrgrade. -FahFenbeit. Centigxade, Fahrenheit. -73. ' — 1000 -24 -■ — II-2 -72: " -97-6 -23 ' - 93' -71 -95-8 — 22 - 7-6 -70 -94-0 -21 , -5-8 ,-69 -92-2 — 20 - 40 -68 -90-4 -19 — 2-2 -67 -88-6 -18 - 0-4 -66 -86-8 -17 + 1*4 -65 -850 -16 , + 3-2 -64 -83-2 -15 + 50 i -63- -81-4 -'4 - - -.4--^•8- -62 -79-6 - [3 + 8-6 -61 -77-8 --12 " ■ + 10-4 1 -60 — 760 -II + I2f2 j -59 -742 .: ^ 10 -+ I4-0' ^.-58 - -72-4 - ' ^ 9 + 15-8 - ■%'- ; -57 -.707 , - 8 - + 17-6 : r'r.:; -56 -: -68-8 • ,- 7 ..: :+>r4: ' ' ■/-55. .-^ —t>y-6 - 6 + 21-2 ' -54 , -65-3 : - 5 ': -' ' ' +23-0 - -V : - -53 -63-4 - 4 .' +.24-8 1 c>. \c^'-S2 ] -6i-6 - 3 - '^+26^6 ■ - ' : (\'.-5i.'.:" -^9-8 . — 2 " +28-4 Q-B -58-0 ; — I ' ' — <■■ ;^'. -48::: ^-54•4 4, I ^. .iv;:+3^8-;; ' '- (,V-^47; -: .-52-6 .,: :'v 2 1 ^ "^:+3s^6;,j -^.-46 ,s ; -^50-8 . .: . r'M- 3 ■ :\' + 37:^4! : ::/+39-2: ^ ■V' 1 ^' ■-. -45^ - :.-r49-o^. ^ '\^'. 4 ; s ' ~-44^-'.- : ^-.-47 -2 . ^ ^.-^: 5 ; ^ -';' ^+4i-G- ' i':^i .,-43 -: ^-45•4■. - +; 6 •: :. :+42-8"' ''•':- !■ '-. -42:.:: ::.-43-f>-..: ;.+: 7 - •,+446 ■ -41 ;:-^ii-8 r- 1 8 ,.:;;+46-4' 1 -40 , - —t^Q-O + 9 " - : + 48-2 '^ - -32 = ~ ;-i8-2 ,: ■ 4- 10 . ; + 50-0 -38 : ,-;6-4 , + 11 - : + 5i-8 L---^' . -37 ^ — 34-6 , > f_ 1 2 . +53-6 •. ' ■ 1 -3(> /" -;32-8 . ■ !+:i3 t: : + 55-4\- -3S-.~ .-310 , : +14 ; ^^" + 57'2: , — 34^ - ,-:29-2 .+:i5 + 59-0 -33 / - -27-4, .■ + 10 ^ ; + 6o-8 j -32 . —25-6 : ^ +J7 : :+62-6 -31 - —'2y8~. : +18 ^ :+64H " -30 —220 +.19 + 66-2 -29 — 20-2 +.20 + 68-0 -28 . -18-4 :, -I-:"2I ! ] ; + 69-8 :-27 ., , -t6-6 /:l-'^2 ' '^ + 71-6 ■ -26^ " ' -^14-8 - +^3 ^ - +73'4- -25 -[3-0 + 24 1 75-2 244 REFRIGERATING AND ICE-MAKING MACHINERY. Comparison of various Hydrometer Scales. — Yaryan. Specific Gravities. u ^ i 'qT g ^1^ Iffl 3 H ^1 rt rt 1 3 1^ ^6 2'- c 1^ If ,i^ t^ r^ M M lo'i u2 2 ■ P 1 % 11 Q 0" 1" to r I -000 I -0000 o-o 0-0 0-0 O-O 0-0 0-0 I 1-007 1-0070 0-7 1-4 2-8 1-2 1-8 0-4 2 1014 1-0x40 1-4 2-8 5-5 ^•i 3-6 i'4 3 I -02 I 1-0215 2-1 4-2 8-2 3-5 5-4 2-1 4 1-028 1-0285 2-8 5-6 10-9 4-6 7-1 2-7 5 1-036 I -0380 3-6 7-2 I3'9 5-9 9-0 3-5 6 1-043 1-0435 4-3 8-6 16-5 7-0 10-7 4-1 7 1-051 1-0510 5-1 IO-2 19-4 8-3 12-6 4-8 8 1-058 1-0585 5-8 II-6 21-9 9-3 14-3 5-5 9 1-066 1-0665 6-6 13-2 24-8 10-4 16-1 6-2 10 1-074 1-0745 7-4 14-8 27-5 11-7 18-0 6-9 II 1-082 1-0825 8-2 16.4 30-3 12-9 19-8 7-6 12 1-090 1-0905 9-0 18-0 33 -o 14-1 21-5 ^•3> 13 1-098 1-0990 9-8 19-6 36-0 15-2 2yz 8-9 14 I-IO7 I-I075 10-7 21-4 39-0 164 25-2 9-7 15 I-II5 1-1160 11-5 23-0 41-3 17-6 27-0 10-3 16 1-124 1-1245 12-4 24-8 44-2 18-8 28-9 ii-o 17 I-I33 I-I335 13-3 26-6 46-5 20-0 30-7 11-7 18 1-142 1-1425 14-2 28-4 49-7 21-2 32-6 12-4 19 1-151 1.1515 15*1 30-2 52-5 22-3 34'4 13-1 20 1-160 I. 1607 i6-o 32-0 55-2 23-5 36-2 13-8 21 1-169 1-1705 16-9 33-8 57-8 24-6 38-0 14-5 22 1-179 I-I795 17-9 35-8 60-7 25-8 40-0 15-2 23 I-I88 1-1895 i8-8 37-6 63-3 26-9 41-7 15-8 24 1-198 1-1995 19-8 39-6 66-1 28-1 43-6 i6-5 25 1-208 I -2095 20-8 41-6 68-9 29-3 45-5 17-2 26 I-2l8 1-2195 21-8 43-6 71-6 30-4 47-3 17-9 27 1-229 1-2300 22-9 45-8 74*5 31-7 49-4 i8-6 28 1-239 1-2405 23-9 47-8 77-2 32-8 51-2 19-3 29 1-250 1-2515 25-0 50-0 79'3 34-0 53-2 20-0 30 1-261 1-2625 26-1 52-2 82-8 35-2 551 20-7 31 1-272 1-2735 27-2 54-4 85-5 3b'4 57-0 21-4 32 1-283 1-2850 28-3 56-6 88-3 37-5 58-9 22-1 Z?> 1-295 1-2960 29-5 59-0 91-1 38-8 609 22-8 34 1-306 1-3080 30-6 6i-2 93-7 39-9 62-7 23-4 35 1-318 1-3200 31-8 63-6 96-5 410 64-7 24-1 USEFUL TABLES AND MEMORANDA. 245 Comparison of various Hydrometer Scales. — Yarya7i. Contmued. Specific Gravities. cJ l-c k , _u ID 1 c/5 . ^ 0. a . " r 1 i I •^1 II 1 1 HO r 1 i II go 2 u i 3 6 1 8 H 1 P -as S §11 sw 0, & ft s^ y^ d oj a IS* -52 Q ^ I 36 1-330 1-3320 33-0 66-0 99-2 42-2 66-7 24-8 37 1-342 1-3445 34-2 68-4 101-9 43-3 68-6 25-5 38 1-355 1-3570 35-5 7I-0 104-7 446 70-7 26-2 39 1-368 1-3700 36-8 73-6 107-6 45-8 72-7 26-9 40 1-381 1-3830 38-1 76-2 IIO-3 46-9 74-7 27-6 41 i'394 1-3955 39-4 78-8 113-5 48-0 76-7 28-3 42 1-408 I -4100 40-8 8i-6 115-9 49-3 78-8 28-9 43 1-421 1-4240 42-1 84-2 118-5 50-4 8o-8 29-6 44 1-436 1-4380 43-5 87-0 121-3 51-5 82-9 30-3 45 1-450 1-4525 45'0 90-0 124-1 52-8 85-1 31-0 46 1-465 1-4675 46-5 930 126-7 53-9 87-2 1^-1 47 1-479 1-4827 48-0 96-0 129-7 55-1 89-4 32-4 48 1-495 1-4980 49-5 99-0 132-4 56-3 91-5 33-1 49 1-510 1-5^35 51-0 102-0 135-1 57-4 93-6 33-8 50 1-526 1-5300 52-6 105-2 137-9 58-6 34-5 51 1-542 1-5460 54-2 108-4 140-6 59-8 35-2 52 1-559 1-5630 55-9 III-8 143-4 61-0 35-9 53 1-576 1-5800 57-6 115-2 146-2 62-2 36-6 54 1-593 1-5965 59-3 118-6 148-9 63-3 37-2 55 r6ii 1-6150 61-1 122-2 151-7 64-5 37-9 56 1-629 1-6335 62-9 125-8 154-5 657 38-6 57 1-648 1-6520 64-8 129-6 157-3 66-9 39-3 58 1-666 1-6715 66-7 133-4 160-0 68-0 40-1 59 1-686 1-6910 6S-6 137.2 162-8 69-2 40-7 60 1-706 1.7110 70-6 141-2 165-5 70-4 41-4 61 1-726 1-7315 72-6 145-2 168.3 71-5 42-1 62 1-747 1-7525 74-7 149-4 171-0 72-7 42-8 63 1-768 1-7740 76-8 153-6 173-8 73-8 43-4 64 1-790 1-7950 79-0 158-0 176-5 75-0 44-1 65 1-812 1-8185 81-2 162-4 179-3 76-2 44-8 66 1-835 1-8420 83-5 167-0 182-0 77-4 45*5 67 1-859 1-8660 85-9 171-8 184-8 78-6 46-2 68 1-883 1-8910 88-3 176-6 187-5 79-7 46-9 96 1-907 1-9151 90-7 181-4 190-2 80-9 47-6 70 1-933 1-9410 93-3 186-6 193-0 82-1 48-3 72-5 2-000 2-0085 1000 200 -o 200-0 85-0 50-0 246 REFRIGERATING AND ICE-MAKING MACHINERY, "- ' " Pressurk of Water. IVorthington Pumping Eiigine Company. The pressure of water in pounds per square inch for every foot in height to 270 ft. By this Table, from the pounds pressuie per square inch the feet head is readily obtained, and vice versa. 'C :; c 'H c G.C fe-S -i c 1 '^ = u — .a ii ffi %t w U5 C* K 3 _ii ^ 3 • W. It i- % 5^ u ^ s >- h t; ^ u. t ■ 11 % f^S- . ^ f^P, ^ ^ ^ ^. f^i f^ Pi p, £^ ^^ I 0-43 46 19-92 91 39-42 136 58-91 181 78-40 226 97-90 2 0-86 47 20-35 92 39-85 137 59'34 182 78-84 227 98-33 3 1-30 48 20-79 93 40-28 :13s 59-77 183 ! 79-27 228 98-76 4 173 49 21-22 94 40-72 139 6o-2i 184 j 79-70 229 99-20 5 2-ib 50 21-65 95 41-15 140 60-64 185 80-14 230 99-63 6- 2-59 5' 22-09 96 4^-58 141 61-07 1S6 80-57 231 100-06 7 3-03 52 22-52 97 42-01 142 61-51 1B7 81-00 232 100-49 8 3-46 53 22-95 98 42-45 143 6T-94 188 81-43 23s 100-93 9^ 3-89 54 23-39 99 42-83 144 62-37 189 81-87 234 101-36 10^ -4-33 55 23-82 ICO 43-31 145 62-81 190 82-30 235 10179 11^ . 4"76 56 24-26 10.1 43-75 146 63-24 191 82-73 236 102-23 12' 5-20 57 24-69 102 44-18 147 63-67 192 83-17 237 102-66 13 5-63 58 25-12 103 44-61 148 64-10 193 83-60 238 10309 H 606 59 25-55 104 45-05 149 64-54 194 84-03 239 103-53 15 6-49 60 25-99 105 45-48 150 64-97 195 84-47 240 103-96 lb- 6-93 61 26-42 106 45-91 151 65-49 196 84-90 241 104-39 17 7-36- 62 26-85 107 46-34 152 65-84 197 85-33 242 104-83 18 , 7-79 63 27-29 108 46-78 153 66-27 I9S 85-76 243 105-26 19 8-22 64 27:72 109 47-21 154 66-70 199 86-20 244 105-69 20 8-66 ^5 28-15 no 47-64 155 67 14 200 86-63 24s iob-13 21 9-09 '66 28-5^ III 48-08 156 67-57 201 8707 246 106-56 22 9-53 -67 29-02 1 12 48-51 157 68 -oo 202 87-50 247 106-99 23 9-96 '68 29-45 113 48-94. 158 68-43 203 87-93 248 107-43 24 10-39 69 29-88 114 49-38 159 68-87 204 88-36 249 107-86 25- 16-82 70 30-32 115 49-81 160 69-31 20s 88-80 250 108-29 ?6 n-26 71 30-75 116 50-24 161 69-74 206 89-23 251 108-73 27 11-69 "2 31-18 117 50-68 162 70-17 207 89-66 252 rQ9-i6 28 12-12 '73 31-62 118 5^-11 163 70-61 20.8 90-10 253 109-39 29: 12-55 '74 32-05 119 5^-54 164 71-04 209 90-53 254 110-03 30 12-99 ^'5 32-48 120 51-98 '^? 71-47 210 90-96 255 1 10-46 31 13-42 76 32-92 121 52-41 166 71-91 211 91-39 256 1 10-89 32 13-86 " 77 33-35 122 52-84 167 72:34 212 ,91-83 257 111-32 33 14-29 78 33-78 123 53-28 168 72-77 213 92-26 258 1 1 1.-76 34 14-72 79 34-21 124 53-71 169 73-20 214 92-69 259 112-19 35 15-16 80 34-65 •25 54-15 170 73-64 215 93- 13 260 112-62 t , 15-59 81 3508 126 54-58 171 74-07 216 93-56 261 1 13-06 37 16-02 82 35-52 127 55-01 172 ' 74-50 217 93-99 262 113-49 3« 16-45 83 35-95 128 55-44 ^73 i 74 94 218 94-43 263 1 13-92 39 16-89 84 36-39 129 5S-88 174 75-37 21.9 ,94-86 264 114-36 40 17-32 l\ 36-82 130 56-31 175 75-80 220 95-30 265 114-79 41 17-75 86 37-25 131 56-74 176 76-23 221 95-73 266 115-22 42- 18-19 87 37-68 132 57-18 177 76-67 222 96-16 267 iiS-66 43 18-62 88 38-12 m 57-61 178 77-10 223.. 96-59 26S -IIJ6-09 44 19-05 89 38-55 134 58-04 179 77-5.1 224 97-03 269 116-52 45 19-49 90 39-98 ^11 58-48 iSo 77<-97 225 ' 97-46 270 116-96 USEFUL TABLES AND MEMORANDA. 247 DiAMEJERS, Areas, and Displacements. IVorthington Piunping Engine Company. u ment rial per avel. ment rial per avel. u ment rial per avel . OJ OJ !/) ,'-' rt (U K «,■- ■" rt u 1; K ,'- E Ji <: ftcH 1 5i u ft cr^ < 5 P-^l Q q-^i Q S.so| I ■0122 -0005 71 41-28 i-:83 i8i 261-5 11-297 1 •0490 •C02I 74 44-17 1-908' l8i i8| 268-8 11-612 f •1104 •0047 7|- 47-17 2-037 276-1 11927 \ •196.:; -CO84 8 50-26 2-171 19 283-5 12-247 •| •3068 -0132 8? 53-45 2-309 19? 291-0 12-571 1 •44' 7 •0190 8^ 56-74 2-451 192 298-6 1 2 900 ■| •6013 •C259 8} 60-13 2-597 I9| 306-3 13-232 I •7854 -0339 9 63-61 2-747 20 3^4-1 13-569 % •0940 •0429 9i 67-20 .2-903 20i 3300, 14-256 1-227 -0530 9\ 70-88 3-062 21 346-3 14960 if 1-484 •0641 91 74-66 3-225 2l\ 363-0 15-681 li i;-767 •0763 10 7:8-54 3-393 22 380-1 16-420 H~ 2-07J 1 -089^ JOi 82-51 3^564 22f 3^7-6 17-176 1 If 2-405 j -1038 ici 86-59 3740 23 415-4 '7-945 t 'i 2-7fci •I 192 io| 90-76 3-920 j 231 433-7 18-735 2 3-I4I -1356 II 95-03 4-105 1 24 452-3 19-539 i 21 3-546 -1531 Hi 99-40 4-294 ^^\ 471-4 20-364 2;- 3-976 -J717 III Ilf 103-8 4484 ^5 490-8 2 1 -202 21" 4-430 •1913 108-4 4-682 25i 510-7 22-062 i ^~ 4-908 •2120 12 1 13-0 4-881 26 530-9 22-935 \ n 5-4" -2337 J2f 117-8 5-088 261 551-5 23-824 i 2i^ 5-939 -2565 122-7 5-300 27 572-5 24-732 i 2| 6-491 '2804 I2I 127-6 5-512 27i 593-9 25-656 1 3 7-068 •3053- 13 132-7 5-732 28 615-7 26-598 ; 3i-: -rm 3313. i3i 137-8 5-952 281 637-,^ 27-567 i 1 3^ 8-295 •3583; 13^ 143 -T 6-182 29 660-5 28-533 3f 8-946 •3864: I3f 148-4 6-410 29I 683-4 29-522 3* 9-621 ■'- •4156- 14 ;i53-9 6-64^ 30 706-8 3«-533 3f 10-32 •4458 Mi 159-4 6-886 31 754-8 32607 ! 3f 1104 •4769 I4i 165-1 7-132 32 804-2 34-741 3i^ i[-79 , •5193 I4I 170-8 7-388 31 855 -;3 36.-949 4 - 12-56 -5426 15 176-7 7-633 34 907-9 : 391-221 4i 14-18 ■ -6125 i5i 1^1 182-6 7-888 35 962-1 41-562 4i 15-90: -6868 188-6 8-147 36 1017-9 43-973 41 17-72 •7655 151 194-8 8-415 37 1075-2 46-448 5 19-63 - -8480 ~ 16 201-0 8-683 38 1134-1 48-993 5^ 21-54 -9348 161 207-3 8-955 39 1194-6 51,-607 5* 23-75 1-026 161 213-8 9-236 40 1256-6 54259 51 25-96 1-121 i6| 220-3 9-516 41- 1320-3 57-037 6 28-27 1-221 17 226-9 9-802 42 1385-4 59-849 6i 30-67 1-325 1 71 nvi 10-095 43 1452-2 62-735 6* 33-18 1-433 17^ 240-5 10-389 4^ 1520-5 65-686 6f 35-78 1-545 •71 247-4 10-687 45 1590-4 68-688 7 38-48 1-662 18 254-4 10-990 46 1661-9 71-794 In estimating the capacity of Worthington (and other duplex) Pumps , [i.e., the deliveiy in gallons per minute or per hour) at a given rate of^ piston speed, it -should be noted that they have i^'ze'i? double-acting water plungers : its capacity, therefore, is c'oub'e that of any ordinary double- ac:irg pump of same size, or four limes as large as a single-acting pump. 248 REFRIGERATING AND ICE-MAKING MACHINERY. Table of Power required to RAISE Water from Deep \Y¥.ULS.— Appleby. Gallons of water raised per hour 200 350 500 650 800 1,000 Height of lift for i man working on crank, in feet 90 S2 S6 28 22 18 Height of lift for i donkey work- ing on gin, in feet .... 180 102 72 4S 3^:' Height of lift for i horse working on gin, in feet 630 357 252 196 i,S4 126 Height of lift for i horse-power steam engine, in feet . . . 990 561 396 308 242 198 Table GIVING Quantity of Water discharged per Minute by Barrel Pumps. — Hutton. fep. / Single barrel. Double barrel. Treble barrel. tS B Length of stroke. r^ 30 strokes 40 strokes 30 strokes 40 strokes 30 strokes 40 strokes Q^ per min. per min. per min. per min. per min. per min. Inches. Inches. Gall^. Galls. Galls. Galls. Galls. Galls. I| 9 ;f 2\- 31 i* 4i 6f 2 9 3 4 6 8 9 12 H 9 6i 9i 12 14 19 3 9 6|- 9 133 18 20 27 3i 9 9t 12J i8|- 25 28 37 4 9 12^ 16 24i 32 36 48 4J 9 i5i 20| 32 42 46 62 5 9 19 25I 38 50 57 76 1^ 9 23? 32 46J 62 69 92 6 9 27I 11 55 73 82 no 2 10 l\ ^\ 9 10 13 2| 10 5i 7 10 14 15 22 3 10 7i 10 15 20 22 30 3i 10 loj nl 20 27 Z^ 42 4 10 i3i 18 27 36 40 54 4i 10 17 23 34 45 52 68 5 10 22 28 42 56 63 84 5i 10 25i 3o| 34 51 68 77 102 10 40 62 82 92 122 2 12 4 5 8 10 12 16 2| 12 6i 8 12 17 19 25 3^ 12 9 12 18 24 27 36 31 12 :i 16 24 11 37 50 4 12 22 32 43 49 65 4i 12 3o| 27 42 55 62 82 5, 12 33 50 68 76 100 5^ 12 42 62 82 92 123 6 12 3^ ■19 /3 97 no 146 6i 12 43 57 86 114 129 172 7 12 50 66 100 134 149 199 7i 12 57 76 114 152 171 229 8 12 65 87 130 174 195 262 9 12 82 no 165 220 246 330 ID 12 102 131 202 268 303 404 T2 12 146 19S 294 390 440 588 USEFUL TABLES AND MEMORANDA. 249 Hydraulic Ram Proportions of the Supply Pipes and Delivery Pipes to the number of Gallons.— ZT^z'/t?/?. Number of gallons to be raised in 24 hours Diameter of fall or supply pipe, in inches Diameter of rising main or de- livery pipe, in inches . . . 500 1,000 2,500 4,000 6,000 Ij 2 ^ 3 4 i I ■i 2 2 Efficiency of Hydraulic Rams. — Hutton. Number of times the height to which the water to be raised is contained in the fall Efficiency per cent. 8 9 10 II I I • 57 S3 48 43 Power Required to Drive Centrifugal, Pumps. Diameter of suc- tion and delivery pipes in inches. Quantity of water delivered per minute, in gallons. Horse-power re- quired for every foot in height the water is raised. I 16 •01 2 50 •02 3 100 •05 4 200 •08 300 •16 6 500 •25 7 700 •35 8 800 •40 9 1,000 •50 10 1,500 1,800 •75 I- 12 2,000 I-0[ 13 2,300 I -08 14 2,500 I-20 1 15 3,000 I-3I ! i i^ 3,500 I -60 1 ^l 3,800 1-75 1 18 1 4,200 2' 2^a REFRIGERATING "AND ICE-MAIvING MACHINERY. \ '■- "' '- : Fthctioxin Pipest ' - - Friction loss in pounds pressure for each lOO ft. in length of cast-iron pipe discharging the stated quantities per minute. — G. A. Ellis, C.E. Sizes of Pipes, inside diameters. 4 3"3 8i3- 12 287 1650-4 2078- 25' 29 33 37; 62 83 103 124 145 166 207 249 290 332 373 621 830 1.037 t,245 1,450 1,660 ,867 2,075 2,490 2,905 3,320 3,735j 4,150, 4,980 0-84 3-16 6-98 12-30 I9'00 275 37" 48- ■r li" •31 •12 ^■°5 •47 2-38 •97 4-07 1-66 6"40 2-62 9'^5 3'75 12-4 5 -OS i6-i 6-52 20-2 8-15 24-9 lO'OO 56-1 22-40 39' 1 48-1 . _ •27 ■42 •67 -•91 1-26 i-6o 2'0I 2-44 5'32 9-46 14-9 2I*2 28-1 37'5 7"7 42 •5' •62 •81 i-8o 3*20 4-89 7"oo 9-46 12-47 19-5'=-^ 28-06 33"4i 42-96 3 4" -6" 8" 10" 12" -10 i •12 ■14 •17 •27 •35 •09 74 .21 I 31 'IZ ■03 I '99 •51 •07 j 2-85 -6q ■10 •02 3-85 •95 ■14 •03 5 -02 1-22 •17 ■05 -01 7-76 1-89 -26 •07 -03 II-20 2-66 •37 •09 •04 •005 15-20 3-b5 •50 -II •05 •007 19-50 4"73 •05 ■15 •06 -01 25-00 _6-oi - -81 •20 •08 :o2j 30-80 7*43 •96 '25 ■°2 3 I4'32 2-21 •53 •18 3-88 •94 •32 •13 ^ . i-4b •49 -20 2-09 ■70 •95 1-23 •49 •63 •77 I'll I i The frictional loss is gi-eatl}- increased by bends or irregularities in the pipe<: TH-r '^"T:tJSEFt?i;Ti:iABi.ES^ and .memoranda. 25.1 DiMteNSTON?:, ETC;, OF STANDARD WROUdAx-lRON Pji>E.'. si ... •rt— ' -So-: Is '11 If ■ ' .'6' ' ^ in ft. per outside . ace. \i ^ i- ^.2 ■ PI 11 ; :W,3!.A 4O '-^. M 3 --27- :,] ■?Oil iyT^ •40 " ^-0573- -'^TM-pi. 9-44- •24 i •36 ■ -29 - — •54 0-1041 1-696^ 7-075- - -42- f8'. !' ■•49 , -42 — •%. : 0-1916 2-I2I 5-657 ^ •56 •18' •62 •54 •24 ■»4- :'o-304r .2;652 4-502 - ;«5, i4. 1 •82 •73 •42 1-05 0-5333 3^299 3-637 ' 1-12 14 I T'©4 ' ^•95 •5^- ^1-31 0-8627 -' 4^^34 2-903 ,1-67 I'l^ li 1-38 1-27 -88 1-66 1-496 5-215 2-301 2-25 I If li I-6I 1-49 I -08 1-90 2-038; ^r- 5-^69 201 2-69^ lit' ■2 2 06 193 ' 1-49 2-37 3'355 ; 7H6I 1-611 3-66 III 4 2-46 2-31 1-75 2-87 4783 9-032 1-328 ,5-77 8 ' 3 3-06 2-89 2-28 3-50 7-388 : 10-996 1-091 7-54 8 3i 3-54 3- 35 2-71 4-00 9-887 12-566 0-955 ■ 9-05 8 4 4-02 3-81 _ 3fi3 4-50 12-730 . . t4-i37 0-849 10-72 8 5 5-04 . _^ 5-56 19-996 ^ vri^^5' ^ 6-629 14-5.6 8 6 6^- . — -. • — - - 6-62 28-889 ~ ' 20-813 ■ 0:577 18-77 8 7 7-02 — — 7-62 38737 23-954 0-.505 23-41 8 8 T98 ■ : -: — T:^ ,8-62 50-039 27-096 0-444 28-35 8 9 9-00 '■ — ' 9-68 63-633 30-433. 0-394 34-07 8 , 10 lO'OI L, '-^ -, "'" -"^ - 10:75 7.8-838 IVTiK: :o-355 46-64: 8 Comparison of British Measures with U. S. Standards. United states standard. -■ - British Standard, ^- I gill =r -833565. imperial gill. _, 4 gills — i,pint ;^. -833565 „ pint. 2 pints ,= J quart zzz- -833565 „ ' quart. 4 quarts = i gallon .= ^833565 „ - .gallon} ^ An imperial gallon = 4*5435 litres = iT9968"U. B; standard gallons. ' : ' An imperial gallon xohtains (Act of Parliament, 1878), 10 lbs. of water at a ternperature of 62° Fahr. Its accepted volume is 277*274 cubic in. . Useful InforiMation. . ,4 gallon of water contains 231 cubic in., and weighs 8^ ibs. (tr! S: standard): ^ ^ :- ^ ■ - ^ 252 REFRIGERATING AND ICE-MAKING MACHINERY. A cubic foot of water contains 7^ gallons, and weighs 62i lbs. The friction of liquids and vapours through pipes increases as the square of the velocity. Sensible heat of a liquid is the amount indicated by the ther- mometer when in)mersed in it. Specific heat is the amount of heat absorbed to produce sensible heat. Latent heat is the amount of heat required for the conver- sion into vapour after a liquid has reached its boiling point. The latent heat of vapour is given off whilst condensing to a liquid ; the sensible heat is retained. One U. S. gallon =1 '133 cubic ft.; '83 imperial gallon; yS litres. An imperial gallon contains 277*274 cubic in. ; '16 cubic ft. ; lo'oo lbs. ; i'2 U. S. gallons ; 4*537 litres. A cubic in. of water = '03607 lb. ; -003607 imperial gallon ; •004329 U. S. gallon. A cubic foot of water = 6*23 imperial gallons; 7*48 U. S. gallons; 28'375 litres; "0283 cubic metre; 62*35 lbs.; "557 cwt. ; "028 ton. A lb. of water = 2772 cubic in.; -lo imperial gallon; •083 U. S. gallon ; "4537 kilo. One cwt. of water = 11-2 imperial gallons; 13-4411. S. gallons ; i'8 cubic ft. A ton of water = 35-9 cubic ft.; 224 imperial gallons; 298*8 U. S. gallons; 1,000 litres (about); i cubic metre (about). A litre of water = '22 imperial gallon ; '264 U. S. gallon; 61 cubic in. ; "0353 cubic ft. A cubic metre of water = 220 imperial gallons ; 264 U. S. gallons; 1*308 cubic yard; 61,028 cubic in.; 35*31 cubic ft. ; 1,000 kilos; i ton (nearly) ; 1,000 Htres. A kilo of water = 2*204 lbs. A vedros of water =2*7 imperial gallons. An eimer of water =2*7 imperial gallons. A pood of water = 3*6 miperial gallons, A "Russian fathom = 7 ft. One atmosphere = 1*054 kilos per square in. One ton of petroleum — 275 imperial gallons (nearly). One ton of petroleum =:: 360 U. S. gallons (nearly). A column of water i ft. in height = '434 lb. pressure per square in. USEFUL TABLES AND MEMORANDA. 253 A column of water i metre in height = 1*43 lbs. pressure per square in. One lb. pressure per square in. = 2-31 ft. of water in height. One U. S. gallon of crude petroleum = 6-5 lbs. (about). Brine for Use in Refrigerating and Ice-making Plants. A brine suitable for the above purpose can be made with from 3 to 5 lbs. of chloride of calcium, or muriate of lime, in accordance with its degree of purity, dissolved in each gallon of water. The density of this solution is about 23° Beaume, its weight about 13^ lbs. per gallon, and the freezing point is — 9° Fahr. As the above standard of density must be kept up, in order to prevent the brine from becoming congealed in the refrigerator, or the ice-making tanks or boxes, it is desirable to test it periodically with a salinometer. In the best American practice first quality medium ground salt, preferably in bags for convenience of handling, is em- ployed, the proportions being about 3 lbs. of salt to each gallon of water. The brine is made in a brine mixer, consist- ing of a water-tight box or tank about 4 ft. x 8 ft. X 2 ft., having a suitably perforated false bottom, and a small com- partment, partitioned off at one extremity, communicating with the main compartment through an overflow situated at the upper end of the said partition, and fitted with a large strainer, to prevent the passage into the said compartment of salt or foreign bodies. The water is admitted through a perforated pipe situated beneath, and running the full length of the false bottom, and the brine is removed through a pipe from the upper part of the end compartment, at the lower extremity of which latter pipe is a strainer-box and strainer through which the brine passes before d eh very into the brine-tank. A salt gauge, salinometer, or hydrometer is also placed in the said end compartment. The salt should be dissolved in the water until it reaches a density of about 90° by the hydrometer. To facilitate dissolution it is desirable to stir the salt in the mixer with some handy implement, the said salt being shovelled in as fast as it can be got to dissolve. By the use of this mixer the settlement of salt on the bottom, and on the coils in the brine tank, which inevitably results when the dissolution is effected directly in the latter, is avoided. 2 54 REFRIGERATIXG AND ICE-MAKIXG MACHINERY. To maintain the strength of the brine it is recommended to suspend bags filled with salt in the brine tank, or to pass the return brine through the above-described brine maker or mixer. Formula for calculating the A.^iount of Air delivered PER Hour by Cold-air Machines, when the Revolu- tions AND the Size of the Compressors are known. This is given as follows by Messrs. Haslam in their Catalogue of ice-making and refrigerating machinery : — A- ^■ ^ J ^ A X N X 2R X S X 60 ^^ ^, Air discharged per hour = X C 1728 Where A = Area of each compressor in inches. N = Number of compressors. 2R z= Strokes per minute (or twice the revolutions). 60 = ]\Iinutes per hour. S = Stroke in inches. 1,728 = Cubic inches in one foot. C = Factor of efficiency which is taken as "8 for short strokes, and "85 for long strokes. Information required by Manufacturers to enable THEM to estimate FOR THE COST OF A REFRIGERATING Plant. 1. The length, breadth, and height of the cellars, rooms, 01 stores to be refrigerated. If the ceiling or roof is vaulted, the height to the centre and spring of the arch w^ill be required. Full particulars of the means of insulation adopted; or if none exist, of the materials from which the chambers are built. 2. Whether it is desired to refrigerate on the direct expansion, or on the brine circulation system. 3. The temperature desired to be maintained in each cham- ber or store. 4. The nature of the substance which it is desired to refri- gerate. 5. In the case of a packing-house, or an abattoir, the largest number of carcasses to be cooled daily, and their average weight. 6. In the case of a freezing cliamber for beef, mutton, or other produce, the number of carcasses, &c., to be frozen in each 24 hours, and their average weight. 7. When a liquid is to be cooled, the number of gallons, or USEFUL TABLES AND MEMORANDA. 255 barrels, to be dealt wiih per hour, and from what temperature down. 8. The nature, quantity, and temperature of the water supply available for use. 9. Rough dimensioned plan of the establishment showing the most convenient spot to locate the refrigerating machine. Information required byMai^ufacturers to enable them TO estimate for the cost of an Ice-making plant. 1. Num.ber of tons of ice that it is desired to produce per 24 hours. 2. If clear, crystal, transparent ice is required, or whether opaque ice will do for the purpose. 3. The nature, quantity, and temperature ot the supply of water procurable for use. 4. Whether there is an available source of steam supply on the premises ; and if spare steam-power, then how many horse- powder could be utilised. 5. When the installation is to be erected in existing buildings, a rough dimensioned plan of same. 6. Where an estimate of cost of making ice is required, price and quality of fuel ; wages of engine drivers, stokers, and common labourers, for 12 hours day work, and for 12 hours night work ; if water has to be bought, cost of same. 256 REFRIGERATING AND ICE-MAKING MACHINERY. Loss OF Pressure by Friction of Compressed Air in Pipes. F. A, Halsey. 6 Cubic feet of Free Air compressed to a Gauge Pressure of 60 lbs. per Diameter of Pip Square Inch and passing through the Pipe per Alinute. j 50 75 100 125 150 200 250 300 400 600 Loss of Pressure in Pounds per Square Inch for each 1,000 Feet of Straight Pipe. ins. lbs. 10-40 lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. lbs. \\ 2-63 .S-QO li 1-22 2 75 4-89 7-b5 II -oo 2 •35 79 1-41 2°20 3-17 5^64 878 4 •14 •32 •57 •90 1-29 2-30 3-5« 5-18 9-20 3 •II •20 •31 •44 ■^^ 1-23 177 3-14 7-05 3* •15 •21 •3« •59 •«5 1-51 3-40 4 •20 •3' •45 •80 i^8i 5 •10 •^5 •26 •59 6 .23 Friction of Air in Tubes. — Unwin, '■'■ Miii. Proceedings Inst. C.E. a k — coefficient of friction TJ + b, a and b being constants, and V = velocity of air feet per second. Diameter of tube, ft. 1-64 [•07 •83 •338 •266 •164 Value of (2 . •00129 •00972 ■01525 •03604 •0379 •04518 „ b . . •00483 •0064 •00704 •00941 •009S9 •01167 ,, i^ifz/^ioo •004S4 •0065 •00719 •00719 ■00997 •01212 USEFUL TABLES AND MEMORANDA 257 Coefficients for Efflux of Air from Orifice,^. Molesu'orth, Vena contracta . . . , . •9S Conical converging . • '9 Cylindrical rounded at ends • '9 Cylindrical throughout . -8 Thin plates . , . « . -6 Centrifugal Fans. — Molcsworth, D = Diameter of fan. V = Velocity of tips of fan in feet per second. P == Pressure in lbs. per square inch. V = n/P X 97300- V2 P - 97300 Power required for Y h'^'&.^-Molesworth, P =: Pressure of blast in lbs. per square inch. A := Area of the sum of the tuyeres in square inche.^ V = Velocity of tips of fan in feet per second. HP ■-= Indicated horse-power required. TIP .= -000016 V^ A p. Proportions of Fans. — MoleswortK D L-enoth of vanes — . — Width of vanes = — . ^4 4 Diameter of inlet •-— — . Eccentricity of fan — ---. 2 10 Length of spindle journal = 4 diameters of spindle. 258 REFRIGERATING AND ICE-:MAKING MACHINERY. Solubility of Ammonia in Watrr at difff.rent Temperatures AND Pressures. — Sims. I lb. of water (also unit volume) absorbs the following quantities of ammonia. Absolute 32° F. 68° F. 104° F. 212^ F. Pressure in lbs. persq. in. lbs. vols. lbs. vols. lbs. vols. grms. vols. 14-67 0-899 i-i8o G-518 0-683 0-338 0-443 0-074 0-Q7 i5"44 0-937 1-231 o'535 0703 0-349 0-458 0-078 0-102 16-41 0-980 1-287 0-556 0-730 0-363 0-476 0-083 0-109 17-37 1-029 1-351 0-574 0-754 0-378 0-496 0-088 0-II5 18-34 1-077 1-414 0-594 0-781 0-391 0-513 0-092 0-I20 19-30 1-126 1-478 0-613 0-805 0-404 0-531 0-096 0-126 20-27 I-I77 ^-546 0-632 0-830 0-414 0-543 o-ioi 0-132 21-23 1-236 1-615 0-651 0-855 0-425 0-558 o-io6 0-139 22-19 1-283 1-685 0-669 0-878 0-434 0-570 c-iio 0-140 23-16 1-336 1-754 0-685 0-894 0-445 0-584 0-II5 0-151 24-13 1-388 1-823 0-704 0-924 0-454 0-596 0-I20 0-I57 25-09 1-442 1-894 0-722 0-948 0-463 0-609 0-I2C; 0-164 26-06 1-496 1-965 0-741 0-973 0-472 0-619 0-130 0-170 1 27-02 1-549 2-034 0-761 0-999 0-479 0-629 0-135 0-177 1 1 27-99 1-603 2-105 0-780 1-023 0-486 0-638 1 28-95 1-656 2-175 0-^01 1-052 0-493 0-647 . 30-88 1-758 2-309 0-842 I -106 0-511 0-671 32-81 1-861 2-444 0-88I I-I57 0-530 0-696 34-74 1-966 2-582 0-919 1-207 0-547 0718 . 36-67 2-070 2-718 0-955 1-254 0-565 0-742 . 38-60 0-992 1-302 0-579 0-764 . 40-53 0-594 0-780 Temperatures adapted for the Cold Storage of Various Articles. — Ice and Refrigeration, dr-'r. Articles. Meats (fresli) . ,, (canned) Fish (fresh) .' ,, (dried) . Oysters . . . ,, (in tubs) ,, (in shells) Butter . . . Butterine . . Oleomargarine Cheese . . . degs. Fahr. 34 35 25-30 35 33-35 25 32-38 35 35 32-33 Articles, Eggs . . . Poultiy (frozen) ,, (to freeze Game (frozen) ,, (to freeze) Oil ... . Sp-up . . . Honey . . . Beer (in barrel) „ (bottled) Cider . . . degs. Fahr. 33-35 28-30 18-22 25-28 15-28 35 55 45 33-42 45 30-40 USEFUL TABLES AND MEMORANDA. 25Q Temperatures adapted for the Cold .Storage of Various Articles . — Continued. Articles. de-s. Fabr. 1 Ginger ale ..... 36 | Wines . . . 40-45 Apples . . . 32-3^ Bananas . . 40-45 Berries (fresli) 36-40 Cranberries . 34-3^ Canteloupes . 40 Dates, figs, &c. 55 Fruits (dried) . 35-40 Grapes . . . 36-38 Hops . . . 33-40 Lemons . . 36-40 Oranges . , 45-50 Peaches . . 45-55 Pears . . . 34-36 Watermelons . 34 Parsnips . . • 34 Oelery . . . 32-34 Carrots . 34 Cabbage . . . 34 Articles. Asparagus . Sauerkraut Potatoes . Onions . . Nuts . . Peas (dried) Com (dried) Beans (dried) Chestnuts . Wheatflour Oatmeal Buckwheat flour Sardines (canned) Fruits (canned) Meats (canned) Cigars . . . Furs (undressed) Furs, woollens, & Tobacco Sugar, &c. degs. Falir. 34 35-38 36-40 34-40 35 40 35 32-40 IZ 40 40 40 35 35 35 35 35 25-32 35 40-45 Rough Estimate of Refrigeration in Breweries. A ready method of obtaining a rough estimate in tons of the amount of refrigeration required in a brewery is to divide the capacity of the brewery in barrels by 4. Amount of Refrigerating Pipes Necessary for Chilling, Storage, and Freezing-chambers. Chilling-rooms or Chambers, refrigerators on the direct expan- sion system, i-ft. run of 2-in. piping for each 14 c. ft. of space ; on the brine-circulation system, i-ft. run of 2-in. pii)ing for each 8 c. ft. of space. Freezing-rooms or Chambers, refrigerated on the direct expan- sion system, i-ft. run of 2-in. piping for each 8 c. ft. of space; on the brine-circulation system, i ft. run for each 3 c. ft. of space. Storage-rooms or Chambers, refrigerated on the direct expan- sion system, i-ft. run of 2-in. piping for each 45 c. ft. of space ; on the brine-circulation system, i-ft. run of 2-in. piping for each 15 c. ft. of space. 2 60 REFRIGERATING AND ICE-MAKING ]MACHINERY. Table showing Properties of Saturated Steam. — I ary Absolute Pressure from Vacuum. Above Atmosphere. Heat of Tempera- ture. Total Heat in Vaporiza- tion lbs. per Inches lbs. per Inches British or Latent Square of Square of Deg. Fahr. Units. Heat. In. Mercurj-. Mercur)'. I 2-0355 -13-7 -27-886 101-99 III3-I 1043-0 2 4-0710 -12-7 -25-851 126-27 II2O-5 IO26-I 3 6-1065 -II-7 -23-815 141-62 1125-r 1015-3 4 8-142 -10-7 — 21-780 153-09 II28-6 1007-2 5 10-178 -9-7 -19-744 162-34 "31-5 1000-8 6 12-213 -8;7 -17-709 170-14 1133-8 995-2 7 14-249 ~7'7 -15-673 176-90 1135-9 990-5 8 16-284 -6-7 -13-638 182-92 1137-7 986-2 9 18-320 -5-7 -11-602 188-33 1139-4 982-5 lO 20-355 -4-7 -9-567 193-25 1 140-9 979-0 II 22-319 -Z-i -7-531 1.97-78 1 142-3 975-8 12 24-426 -2-7 -5-496 201-98 1 143-6 972-9 13 26-462 -1-7 -3-460 205-89 1144-7 9701 14 28-497 — 7 -1-425 20^-57 1145-8 967-5 147 29-922 0-0 o-ooo 2I2-00 1146-6 965-8 15 30-533 0-3 0-6II 213-03 1146-9 965-1 16 32-568 1-3 2-646 216-32 1147-9 962-8 17 34-604 ^'Z 4-682 219-44 1148-9 960-6 18 36-639 yZ 6-717 222-40 1 149-8 958-5 19 38-675 4-3 8-753 225-24 1150-7 956-6 20 40-710 5'3 10-788 227-95 1151-5 954-6 21 42-746 6-3 12-824 230-55 1152-3 952-8 22 44781 7-3 14-859 233-06 1 153-0 951-0 23 46-787 8-3 15-895 235-47 1153-7 949-2 24 48-852 9-3 18-930 237-79 1154-4 947-6 25 50-888 10-3 20-966 240-04 II55-I 946-0 26 52-923 II-3 23-007 242-21 1155-8 944-6 27 54-972 12-3 25-043 244-32 1156-5 943-1 28 57-008 13-3 27-079 246-36 1157*1 941-7 29 59-044 14-3 29-115 248-34 1157-7 940-3 30 61-080 15-3 31-143 250-27 1158-3 938-9 31 63-116 i6-3 33-187 252-15 1158-8 937-5 32 ^5"'^? T^ 35-223 253-98 , 1159-4 936-3 33 67-188 18-3 zr2Z9 255-76 1159-9 935-0 34 69-224 19-3 39-295 257-50 1160-4 933-7 35 71-260 20-3 41-321 25919 1161-0 932-6 36 73-296 21-3 43-367 260-85 1161-5 931-5 37 75-331 22-3 45-319 262-47 1 1162-0 930-3 38 77-367 23-3 47-397 264-06 i 1162-5 929-2 39 I 79-403 1 24-3 50-463 265-61 1163-0 928-2 USEFUL TABLES AND MEMORANDA. 26 Table shoaving Properties of Saturated Steam. Continued. Yaryan. Absolute Pressure from Vacuum. Above Atmosphere. Heat of Tempera- Total Heat Vaporiza- ture. in tion lbs. per Inches lbs. per Inches British or Latent Square of Square of Deg. Fahr. Units. Heat, i In. Mercury. In. Mercury. 40 81-439 25-3 51-499 267-13 1163-4 927-0 41 83-475 26-3 53-534 268-62 1163-9 926-0 42 85-511 ^1-Z 55-58.^ 270-08 1 164-3 925-0 43 87-547 28-3 57-619 271-51 1164-8 924-0 44 89-583 29-3 59-655 272-91 1165-2 923-0 4,S 91-619 30-3 61-691 274-29 1165-6 922-0 46 93-655 31-3 63-727 275-65 1166-0 921-0 1 i 47 95-691 32-3 65-763 276-99 1166-4 920-1 1 48 97-727 33-3 67-799 278-30 II66-8 919-2 1 1 49 99-763 34-3 69-835 279-58 1167-2 918-3 i 50 101-799 35-3 71-871 280-85 1167-6 917-4 1 l^ 111-98 40-3 82-050 286-89 II69-4 913-1 1 60 122-16 45-3 92-230 292-51 II71-2 909-3 65 132-34 50-3 102-410 297-77 1172-7 905-5 70 142-52 55-3 112-59 302-71 II74-3 902-1 l^ 152-70 60-3 122-77 307-38 1175-7 898-8 ^° 162-88 65-3 132-95 311-80 1177-0 895-6 85 173-06 70-3 143-13 316-02 1178-3 892-5 90 185-24 75-3 153-31 320-04 1179-6 889-6 95 193-42 80-3 163-49 323-89 ii8o'7 886-7 100 203-06 85-3 173-67 327-58 1181-9 884-Q 105 213-78 90-3 185-85 331-13 1182-9 881-3 no 223-96 95-3 194-03 334-56 1184-0 878-8 115 234-14 100-3 203-67 337-86 I [85-0 876-3 120 244-32 105-3 214-39 341-05 1186-0 874-0 j 125 254-50 II0-3 224-57 344-13 1186-9 871-7 130 264-68 115-3 234-75 347-12 1187-8 869-4 135 274-86 120-3 244-93 350-03 1188-7 867-3 , 140 285-04 125-3 255-11 352-85 1189-5 865-1 i 145 295-22 130-3 265-29 355-59 1190-4 863-2 i 150 305-40 135-3 275-47 358-26 1191-2 861-2 160 325-76 145-3 295-83 363-40 1192-8 857-4 '^° 345-82 155-3 316-19 368-29 1194-3 853-8 180 366-48 165-3 336-55 372-97 1195-7 850-3 1 190 386-84 175-3 356-9T 377*44 1197-1 847-0 200 407-20 185-3 377-27 381-73 1198-4 843-8 262 REFRIGERATING AND ICE-MAKING MACHINERY Fractions of an Inch and Decimal Equivalents. Fractions. Inch. Fractions. Inch. Fractions. Inch. 1-32 •03125 3-8 •375 23-32 •71875 I-I6 •0625 13-32 •40b25 3-4 •75 3-32 •09375 7-16 •4375 25-32 •78125 1-8 •125 15-32 •46875 13.16 •8125 5-32 •15(^25 1-2 •5 27-32 •84375 3-16 •1875 17-32 •53125 1 7-8 •875 7-32 •21875 9-16 •5625 1 29-32 •90625 1-4 •25 19-32 •59375 15-16 •9375 9-32 '28125 5-8 •625 31-32 •96875 5-16 •3125 21-32 •65625 11-32 •34375 1T-16 •6875 Mean Annual Temperatures of Principal Citifs of the World. Cities. England. Birmingham . Bristol . . Liverpool . . . London . . . - M.inchester . . Mean annual temperature. 48-2 51-7 50-8 50-8 48-8 Scotland. Edinburgh 47^1 Glasgow 49-8 Irela7td. Belfast 52-1 Dublin 50-1 East Indies. Bombay 81^3 Calcutta . ... 82-4 Madras 81 ^9 TVcst Indies: Havanna 79-1 No-^-fh Ame?-ica. Baltimore 54-9 Boston 48-4 Chicago 45-9 Cincinnati 54-7 Llean annual Cities. temperature. Mexico 60-9 Montreal 44-6 New Orleans New York .... Philadelphia . . . Quebec San Francisco St. Louis .... Washington . . . South AmeHca. Buenos Ayres . . . Lima ....'. Quito Rio Janeiro Valparaiso .... Anstj-alasia. Melbourne . . . . Sydney . . . . . France. Bordeaux Boulogne Alarseilles Paris . A ustro-Hungary Buda-Pestb . . . . Vienna 69-1 51-8 52-1 40-3 55-2 55-0 s6-2 62-8 73-3 to^9 77'2 64^0 57-0 65-8 57^o 54-4 58-3 51-3 47-5 51-0 USEFUL TABLES AND MEMORANDA. 263 MEA.N Annual Temperatures of Principal Cities of the World. — Continued. Cities. Berlin . Breslau . Dresden Frankfort Hamburg Leipsic . Munich . Vienna . Germany. Mean annual temperature. 4»-2 467 49-1 49-6 48-0 46-4 48-4 5I-0 Italy, Florence 59*2 Genoa 61 t Milan 55-1 Naples ...... 60-3 Palermo 63-1 Rome 60-5 Turin 53-1 Venice 55-4 Spain and Portugal. Barcelona 63-0 Madrid 58-2 Lisbon 61*4 Switzerland. Geneva 527 Holland. Amsterdam . . , . 49-9 Rotterdam . . . . 51-0 Mean annual Cities. ^ temperature. Belgium. Brussels ...... 50-7 Norway and Sweden. Cliristiania Stockholm Denmark. Copenhagen . . . Turkey. Bucharest . . . , Constantinople . . 41-5 42-3 46-6 46-4 56-5 Russia. Moscow ..... 40-0 St. Petersburg . . . 39-6 Warsaw 44-2 Palestine. Jerasalem 62-6 Egypt. Cairo 72-2 Barbary. Algiers 64-3 Tunis 68-8 Leaks in Ammonia Apparatus. Leaks are readily detected by the smell of the escaping ammonia gas when the machine is being filled ; at a later stage, when working, their detection is not so easy. During the operation of the machine when the liquor or brine in the tanks commences to smell of ammonia it indicates a considerable leakage. It is recommended to test the liquor or brine periodically with Nessler's solution or otherwise Nessler's reagent, which is the best to use for the discovery of traces of ammonia in water or brine, consists of 17 grms. of mercuric chloride dissolved in about 300 cc. of distilled water, to which is added 35 grms. potassium iodide dissolved in roo cc. 264 REFRIGERATING AND ICE-MAKING MACHINERY. of water, and constantly stirred until a slight permanent red precipitate is produced. To the solution thus formed is added 120 grms. of potassium hydrate dissolved in about 200 cc. of water, allowed to cool before mixing; the amount is then made up to I Itr., and mercuric chloride added until a permanent precipitate again forms. After standing for a sufficient time, the clear solution can be placed in glass-stoppered blue bottles and kept in a dark place. If a few drops of this reagent be added to a sample of the suspected brine or water in a test-tube, or other small vessel, and the slightest trace of ammonia is present a yellow coloura- tion of the liquid will take place ; a large quantity of ammonia will produce a dark-brown. When the leaks are comparatively insignificant they can be closed in the usual way, by solder, using as a flux muriatic or hydrochloric acid killed with zinc. In some instances electric welding may be resorted to with advantage, or the leak may be closed by means of a composition of litharge and glycerine mixed into a stiff paste, bound with sheet-rubber, and covered with sheet-iron clamped firmly in position. When, however, the leak is at all serious it is usually the better plan to at once put in a new coil, or a new length of pipe. Leaks in Carbonic Acid Machines. To detect these, smear the joints with a solution of soap and water, and any leakage of gas will be evidenced by the forma- tion of bubbles. Carbon dioxide or carbonic acid being a completely inodorous gas, great precautions are required to prevent the occurrence of leakage. Heat-conducting Power of Vakious Substances, Slate BEING 1000. — Molesworth. Slate J, 000 Lead 5,210 Flagstone . . . . i,llO Portland stone . . 750 Brick . . . 600 to 730 Fire-brick .... 620 Chalk 564 Asphalte 451 Oak 336 Lath and plaster . . 255 Cement 200 See pages 165 to 171 for results of experiments wilii various other substances. INDEX. ABRUPT rises or falls in air trunks or conduits, loss by, 145 Absolute pressure, 5 temperature, 5 Absorbers, 96, 106, 107, 108, 1 14 Absorption machine, to start work- ing, 98, 100, no process, 93 — 115 cost of making ice and lefriger- atingby, 113, 234 Abstraction of heat, main function of refrigerating machines, 5 by the rapid melting of a solid, 7 cost of making ice by, 238 Accessories, photographic, use of refrigerating machinery in fac- tories of, 204 Accidental escape of ammonia gas, precautions to take, 78 Action of and losses in working ammonia absorption machines, 232 Adiabatic curve, 50 Advantages derived from use of sealing oil in compression ma- chines, 50 of ether machines for warm climates, 3 1 ammonia machines, 36, 93, i:L4 carDonic acid machines, 35 cold-air machines, 137, 142, 144 Affinity of water for ammonia, 78, 102, 230, 256 After preservation of frozen meat, I4S> 258 Agents employed in brine circula- tion system, 96, 147, 253 liquefaction process, 8, 10 the compression process, 21 Agitation, making clear crystal ice by, 209, 210 objections to, 209, 214 Air, amounts of aqueous vapour held in suspension in, at different temperatures, 241 presence of in ammonia com- pression machines, 79 to get rid of when charging an ammonia compression ma- chine, 77 American machine for making ice on the liquefaction principle, 8 Ammonia, use of in refrigerating machines, 21, 31, 36 machines, 36, 39 gas, tight joints for, 108, 153, 154, 155 apparatus, leaks in, to stop, 264 results of tests with, 57 anhydrous, 36, 37 path taken by through refrige- rating plant, 48, 100, 109 qualities of, 37 solubility of in water, 18, 102, 232, 258 accidental spilling of, 78, 232, gas,dif£cultiesin dealing with, 38 lubricating qualities of, 89 compression machines, opera- tion of, 40 management of, jy preliminaries to charging, 77 2 66 INDEX. A.mraonia machines, to chaige, 78 to start worl^in^, 79 leakage, detection of, 92, 262 precautions when breaking joints, 89 cost of working, 30, 57, 234, 236 woik expended in, 237 absorption machines, 93 — 115 advantages of, 93 to start working, 98, lOO, iio operation of, 93 consumption of fuel b}', 98 amount of cooling water re- quired by, 98, 113 cost of working, 113, 234 amount of ammonialosttlirough leakage, 113 horse-power requiied for, 113 gas properties of, 242 anti-putre?cent properties of, 153 no deleterious effect on ircn, 89. 157 pumps for absorption machines, 103, 106, 109, no Amount of refrigerating pipes in chilling, storage, and freezing chambers, to estimate, 259 Amylic ether, use of as a refrigerat- ing agent, 114 Analysers, loi, 103, 104 Anhydrous ammonia, use of as a refrigerating agent, 36 manufacture of, 37 proportion of in ordinary com- mercial ammonia, 38 sulphurous acid, use of as a refrigerating agent, 32 Annual temperature, mean, of prin- cipal cities of the world, 262 Apparatus for lifting ice cans or moulds, 229, 231 blocks or slabs, 231, 232 distillation of raethylic ether, 27 water for ice-making purposes, 222, 227 manufacturing anhydrous am- monia, 37 Apples, first cai go of imported from Australia, 2 Areas, see diameteis, aieas, and dis- placements Argentine Republic, supply of fro- zen mutton from, 2 Arrangement of rooms and cold store-;, 161 refriger-.ting machines, effect of on economical working, 237 Aitilicial butter factories, use of refrigerating machinery in, 199 use of natural ice for refrige- rating purposes, 201 Artificial surfaces of ice for skating, to form, 206 ice, see ice-mak'ng Atmosphere of cold stores or cham- bers, 162 Attemperators in breweries, appa- ratus for cooling water for, 189 working of, 19 1 Attendants required for ammonia machines, 98, 233 Australia, supply of frozen mutton from, 2 Auxiliary cooler for ammonia ab- sorption machine, 105 Aylesbury dairy, refrigerating mi- chine at, 14 BACON curing factories, re- frigeration in, 179 factory chill rooms, arrange- ment of refriserating pipes in, 150, 179, 180 Barrel pumps, quantities of water discharged by, per minute, 246 Battery, brine, for cooling air, 74 Bandelot breweiy cooler or refiige- rator, 193 Beck, W. H., improved ammonia absorption machine, 94, 103 Beef chill rooms, 178, 179 Beer worts, refrigerators for cool- ing, 191, 192, 193, 201 Bell-Coleman cold-air machine, 124 objections to, 142 Binary or dual absorption process, 114 Bisulphide of carbon, use of as a refrigerating agent, 1 14 Black, Dr., discovery of latent heat by, 4 INDEX. 267 Block, Louis, patent valves for am- monia compressor, 46 Blocks of ice, usual sizes of made, 212, 217, 221 Blyth and Southey's vacuum re- frigerating machine, 18 Boiler power required for ammonia absorption machines, 113 Boyle's law, 5 ammonia compressor, 75 Bramwell, Sir Frederick, descrip- tion of early compression machine, 21 Breaking joints in ammonia ma- chines, precautions to be ob- served, 89 Breweries, use of refrigerating ma- chinery in, 188, 189, 193, 197 Brewery, fermenting and yeast rooms, refrigerating machinery for, 193 management of, 196 .Breweries, rough estimate of re- frigeration in, method of obtain- ing, 257 Brine for use in refrigerating and ice-making plants, 96, 147, 253 circulation system, 147 losses with, 158 cooled surfaces, refrigeration of air by contact with, 160 cooling battery, 74 system, making ice by, 228, 229 British measures, comparison of with U.S. standards, 251 Brotherhood's brewery refrigerator, 192 Butter factories, use of refrigerating machuiery in, 199, 204 artificial use" of refrigerating machinery in, 199, 201 r^AMPANIA ss., cold store on V_y board of, 182, 183 Candle works, use of refrigerating machinery in, 197 Can ice-box or tank, 212 system, advantages of, 215 Cans or moulds, mechanism for shifting or moving, 215, 229, 231 Capacity o. refrigerating machine required for a given cold store or chamber, to estimate, 174 Carafes frappes, refrigerating ma- chine for production of, 14 Carbonic anhydride or carbonic acid, use of as a refrigerating agent, 32,35, 264 Carbon dioxide, see carbonic anhy- dride Carbon monoxide or carbonic oxide gas, 35 Carcasses, freezing or congealing, 145, 161 traversing through freezing chamber, 150 freezing or congealing for trans- portation, 161, 162 packing in cold store or cham- ber, 172 Cargo of frozen meat, first brought to this country, 2 Caire, Edmond, sulphuric acid freezing machine, 14 Ferdinand, absorption machine, 93 Catch all, see oil separators and interceptors Cell ice-making tank or box, 219 advantages of, 219, 221 Centrifugal fans, 257 power required for, 257 proportions of, 257 pumps, power required to drive, 249 oil separators or interceptors, 86 Charge of ammonia, proper, in com- pression machine, 78, 92 Charging or filling cans with water for freezing, 215 ammonia compression machine, 78 Cheese factories, use of refrigerating machinery in, 199 Chemical works, use of refrigerating machinery in, 204 Chill rooms, arrangement of re- frigerating pipes in, 147, 149, 150 construction, &c., of, 163, 178, 179, 180 Chilling rooms or chambers, to esti- mate amount of refrigerating pipes for, 259 268 INDEX. Chimogene, use of in refrigerating machine, 31 Chloride of calcium, for making brine, 96, 147, 253 of sodium or common salt, 96, 147, 253 Chocolate and cocoa manufactories, use of refrigerating machinery in, 188, 204 Chocolate and cocoa, use of re- frigerating machinery in manu- facture of, 188, 204 Christiansen, see Alackay and Chris- tiansen Cities principal, mean annual tem- peratures of, 262 Clark, D. K., tests with respect to non-conducting properties of various substances, 171 Clear crystal ice, methods of mak- ing, 209 block ice, cost of producing with ammonia machines, 232 Coal, consumption of by cold-air machines, 147 Cocks or valves, expansion, 29, 70, 80, 107 Coefficients for efHux of air from orifices, 257 Cold air, admission of to cold cham- bers, &c., 144 system, 116 machines, 116, 117, 118, 119, 122, 12^, 126, 127, 131, 133, 135 cost of producing cold with, 237 management of, 143 results of test experiments with, 143 brine, passing refrigerated air through, 160 stores and chambers, 161 arrangement of pipes in, 162 marine, inspection of, 173 construction and insulation of, 163, 172, 181, 182, 183 closing up of when filled, 174 small, 175, 177 number of times cubical con- tents of the au: should be cooled, 1 75 Cold chambers, admiision of cold air to, 172 temperatures of, adapted for storage of various articles, 256 Coleman, J. J., on experiments v;ith non-conducting substances, 170 see also Bell-Coleman Collectors, separators, or intercep- tors, oil, 48, 69, 85, 86 Colliery shafts sinking in quicksand soils, use ofrefrigeratingmachinery for, 205, 206 Collins, W. H., on comparative value of various non-conducting substances, 171 Colyer, Frederick, results of tests of working of ether machines, 30 calculations as to cost of work- ing of ammonia absorption machine, 233, 234 Combination of direct expansion and brine system, making ice by, 66, 229 Combined arrangement for cooling water for attemperating, and air in fermenting and yeast rooms of bieweries, 196 Commercial ammonia, see common ammonia Common ammonia of commerce, 37, 38> 113 Comparison of Cent, and Fahr. thermometer scales, 243 various hydrometer scales, 242, 245 British measures M'ith U.S. standards, 251 Compensating chamber for am- monia compression machine, 58 Complete installations of refrigerat- ing plants on ammonia compres- sion system, 46, 58, 63, 74, 183 Compound or dual liquid, use of as a refrigerating agent, 114 Compression process, 21, 36 machines, essential parts in, 23 Compression machines_, cost of work- ing, 30, 57» 236 Compressor for treating the gas in I two stages, 33, 72 INDEX. 269 Compressors, ammonin, lubrication of, 42, 54, 82, 89 Concentrator, for dilute sulphuric acid, 15 Condensers, 15, 22, 23, 24, 25, 26, 28, 31, 34, 39, 48, 49, 62, 66, 98, loi, 102, 104, 105, 107 Condensing pressure, excess, 91 water, amount required in ellier machines, 30, 31 ammonia compression ma- chines, S;^ absorption machines, 113 Conducting powers of various sub- stances, 165, 168, 169, 171, 264 Containers, water, 103 Continuous acting ammonia absorp- tion machine, 94 Coolers, 68, 97, 102, 103, 105, IIS, 119, 122, 126, 131, 135, 136 Cooling water for jacket ofammon a compression cylinders, amount required, 83 pipes on direct expansion sys- tem, care of, 157 brine circulation system, ob- stiuctions m, 159 scaling and lubricating oil for ammonia compressors, 42, 72 Cool bed or cool ship in brewery, 193 Cork as a material for insulation of cold stores or chambers, 163 Corrugated brine cooling battery, 74 Cost of working refrigerating ma- chinery, 30, 57, 98, 113, 2^3, 234, 236 Cream coolers, 204 frozen trade in, 3 Creams, icing or freezing, 7 Cullen, Dr., vacuum machinery of, ^3 experiments by, with ether, etc., 21 Cunard Company's steamers, cold stores on board of, 182 Curing cellars of bacon factories, 179 Cycle of operations in an ether machine, 22, 23 ammonia machine, 40 Cyrogene, use of, as a refrigeraling agent, 31 DAIRIES, use o- refrigerating machinery in, 199, 202 Davy, Sir Humphry's theory of heat, 3 De-aerated water, making ice with, 209, 221 De-aerating water, methods of, 221, 222, 224, 228 Definitions of heat, 3 Dehydrator, see Drier De La Vergne single-acting am- monia gas compressors, 42 double-acting ammonia gas compressors, 46 expansion valve or cock, 80 oil separator, 48 pipe joint, 153 stop-cocks or valves, 155 discs or gills for increasing cooling surface of pipes, 150 beef chill room, 178 arrangement for cooling fer- menting room in brewery, 195 installation in a skating rink, 206 ammonia compression ma- i chines, cost of working, I Delia BeiFa and West's ether ma- chine, 29 I De Marian, specific gravity of pure I ice, 208 De Motay and Rossi's refrigerating agent, 115 Denton, Professor, on the loss of efficiency in ammonia compres- sors, 68 Deposit on exterior of condenser coils or tubes, 88 in interior of ammonia pipes, 88, 108 Diagonal pattern cold- air machine, Diagrams from ammonia compreE- sorSj 50 - 270 INDEX. Diameters, areas, and displace- ments, 245 Dioxide of sulphur as a refiigerating agent, 31 Direct expansion system, refiigera- tion by, 147, 151, 152, 162, 193, 195, 204 economy of, 157 ice-making by, 22S Direct gas-driven cold-air machine, 176 Discharge valves of ammonia com- pression machines, lift of, 82 Displacements, see table of dia- meters, areas, and displacements Dissolution of a solid, production of cold by, 7, 238 Distilleries, use of refrigerating ma- chinery in, 204 Distilling apparatus for de-aerating water, 222, 227 Dobbie, J. G., tests for conductivi- ties of asbestos and kieselguhr, 169 Double and single-acting com- pressors, relative advantages of, 39 Driers or dehydrators, 34, 38, 114, 136 Dry air machines, see cold air sys- tem Dual or binary absorption process, 114 Duplex pumps, estimating capacity of, 247 Duration of tests of ammonia com- pression apparatus, proper, 90 Duterne, Victor, metallic packing, 90 Dynamite factories, use of refrige- rating machinery in, 204 ECONOMISER, or temperature exchangers for ammonia ma- chines, 100, loi, no for cold-air machines, 132, 136 Efficiency, loss of in ammonia com- pression machines, 68, 84 of ammonia compression appa- ratus, to determine, 90 of hydraulic or water rams, 249 Efflux of air from orifices, coefljci- ents of, 257 Emery, C. E., on experiments with non-conductors of heat, 170 Engi7ieer, The, article on heat, 4 Esthonian tribe, freezing by, 7 Estimate of refrigeration in brewer- ies, method of making rough, 259 Ether, use of as an agent in le.rige- rating machines, 21, 24 objections to, 31 advantages of, 31 compression machines, work ci and losses in, 234 Ethylo-sulphurous dioxide as a re- frigerating agent, 115 Evaporation, abstraction of heat by, 12 of liquids, table of, 240 Excess condensing pressure, 91 Exchanger, temperature, 16, loo, loi, no, 132, 136, 141 Exhaust steam from engine, use of for ice-making, 49, 222 Expansion cocks or valves, 29, 70, 80, 107 Expenses, main, in production of artificial cold, 233 Extracting air from water, methods of, 221 FACTORY for making ice, arrangement of, 229 Falkland Islands, supply of frozen mutton from, 2 Fans, centrifugal, 257 Fermenting and yeast rooms, cool- ing air in, 193 Filling cans for freezing, 215 Filteis, air, for cold-air machine, 117 Fittings required for testing the efficiency of ammonia compres- sion apparatus, 90 Fixary ammonia compressor, 57 Fixing and manipulation, effect of, on cost of working refrigerating machinery', 237 Formula lor conversion oi different thermometei- scales. 212 INDEX. 271 Formula for calculating the amount of air delivered per hour by cold air machines, 254 Foundations in quicksand soils, use of refrigeration machines for lay- ing, 205 France, manufacture of ice in by natural evaporation, 13 Freezing mixtures, table of princi- pal, 10 observation on, 9 law governing, 9 carcasses, 149, 150, 161, 162, 259 rooms or chambers, to estimate amount of refrigerating pipes required for, 175, 259 French absorption machine, 114 Fresh provisions, trade in, i Frick ammonia com^pressors, 52 operation of, 55 cost of producing ice with, 234 Friction in pipes, 250, 256 in tubes, of compressed air in pipes, loss by, 256 Frigorific mixtures, see freezing mixtures Frozen mutton and lamb, hanging, 172 Fruit cargo, stowage of, 173 proper temperature for, 173, 259 trade, commencement of, 2 Fry, J. S., first use of refrigerating machinery by, in chocolate fac- torj', 188 Fuel, consumption of with vacuum machines, 16 compression machines, 30, 57 absorption machines, 98, 234 cold-air machines, 147, 239 GALE, A. R., observations by, on moisture in cold-air ma- chines, 140 Gas compressor, action of, 40 driven cold-air machine, 176 motor, advantages of for driv- ing small cold-air machines, 177 Gasoline, use of as a refrigerating agent, 31 Gas-tight joints, 70, 103, 108, 153, 154, 155, 156 Gelatine, use of refrigerating ma- chine for drying, 204, 205 Generators for absorption machines, 94, 100, loi, 105, 109, 113, 115 Giffard's cold-air machine, 118 improved cold-air machine, 1 24 Glue works, use of refrigerating machinery in, 205 Gobert, A., system of shaft sinking, 207 Godell, H. C, portable refrigerating chamber, 164, 187 Gorman, see Siebe Gorman & Co. Gome's cold-air machine, 1 16 Gottbrecht, Dr., experiments of, with respect to the anti-putrescent properties of ammonia, 151 HALL, J. & E., Limited's cold- air machine, 136 system of refrigeration, 149 traversing carcasses through freezing chamber, 150 Hanging frozen mutton, method of, 172 lamb, not required, 173 Hargreaves & Tnglis' cold-air ma- chine, 126 j^^also Hick, Hargreaves & Co. Harrison, James, vacuum machines for the manufacture of opaque ice, 17 : -; ' compression machine, 24 invention of wall or plate sys- tem of ice-making by, 209 vacuum machine, cost of pro- ducing ice with, 238 Haslam, Sir A. S., compound am- monia compressor, 72 corrugated brine cooling bat- tery, 74 cold-air machines, 128, 131, 132 direct gas-driven cold-air ma- chine, 176 water-distilling apparatus, 222 cold-air machine, cost of pro ducing cold with, 239 272 INDEX. Healthy working of an ammonia compression machine, signs of, 79 Heat, true definition of what is, 3, 4 conducting power of various substances, 165, 168, 169, 171, 264 transmitted through a square foot of plate per hour, to find, 166 conductivities of various sub- stances, tables of, 165, 168, 169, 171, 264 Hick, Hargreaves & Co.'s cold-air machine, 136 Hill, absorption machine, 112a refrigerating system of, 150a removal of snow, &c., device for, 150a ice-making, system of, 220a Hog chili room, 180 Holds of vessels for carrying live cattle, cooling of, 206 Hopkinson, Dr., estimate of, for cost of making ice with vacuum machine, 238 description of Windhausen machine by, 14 Hospitals, use of refrigerating ma- chinery for cooling atmosphere of, 206 Hot climates, advantages of ether machines for, 31 Hutton, formula for finding heat transmitted through square foot of plate, 166 Hydraulic rams, proportions of sup- ply and dehvery pipes of, 249 Hydraulic rams, efiiciency of, 249 Hydrometer scales, various, com- parison of, 244, 245 Hydrants, provisions of, desirable in ice factories, 232 ICE, artificial surfaces of, for skat- ing, 206 blocks or pyramids, ornamental, 211 cost of making with ammonia compression machines, 57, 234 Ice absorption machines, 113, 234 ether machines, 30, 237 vacuum machines, 238 by liquefaction process, 238 blocks or slabs, usual sizes oi made, 212, 217, 221 making, 208 making tanks or boxes, num- bers of required for different outputs, 221 various systems of making, 228 factory, arrangement of, 229, 230a;, 230^^ deliver}- machines, 231 store, reftigeration of, 232 1 manufacture of in breweries, 197 Improved oil separator or collector, 86 India, manufacture of ice in, by natural evaporation, 12 rubber works, use of refrigerat- ing machinery in, 205 Industrial appUcations, various, 188 Information required to enable manufacturers to estimate for the cost of a refrigerating plant, 254 ice-making plant, 255 Inglis, see Hargreaves & Inglis Insulation of cold stores or cham- bers, 163, 164, 165, 172, 177, 182, 183 Interceptors or separators, oil, 48, 69,^5,86 Interchangers, lOO, lOi, no, 132, 136, 141 JAMIESON, Professor, experi- ments by, on the thermal con- ducti^dties of various substances, 167 Jamieson, Professor, account by, of pre\ious experiments vdih. non- conductors, 170 Johnson Sc WTiitelaw's absorption machine, 114 Joints for pipes of ammonia com- pression machines, 108, 153, 154, 155 precautions when breaking, 89 Joule's mechanical equivalent of heat, 4 INDEX. 273 KILBURN ammonia compres- sors, 63, 66 pipe joints, 154 stop cocks, 156 marine installation, 183 arrangement for refrigeration in dairy, 202 Kingsford, improvements in vacuum machines by, 14 Kirk, Dr. A. C., cold-air machine of, 117 first use of refrigerating ma- chinery by, for parafi&n oil extraction, 188 LABOUR-SAVING contriv- ances for ice factories, 229 Labour required to work refrigerat- ^ ing machinery, 98, 233 Lager beer, cooling of fermenting rooms and store cellars for, 197 Lamb, frozen, when fit for use, 173 Land installations, cold air inlet trunk or pipe for, 172, 173 Lange's pumps for vacuum ma- chine, 16 Latent heat, definition of, 3, 4 Leakage c£ gas in compressors, pre- vention of, 39, 42, 54, 56, 57, 58, 60, 66, 70, 72 Leaks in ammonia apparatus, to stop, 264 in carbonic acid machines, to detect, 264 Lemonades, icing or cooling, 7 Leslie's improvements in vacuum machines, 14 Lift of suction and discharge valves of ammonia compression ma- chines, 82 Lifts for ice factory, 232 Lightfoot's ammonia compression apparatus, 66 cold air machine, 132 experiments with ether com- pression machines, 30 arrangement for making ice by a combination of the direct expansion and brine circula- tion systems, 227 Lightfoot's observations uponfrigor- ific or freezing mixtures, 9 the effect of the presence of water on heating or cooling of air, 138 carbonic acid as a refrigerating agent, 35 Linde, Carl, improved system of making clear ice by agitation, ammonia compressors, 56 Liquefaction of a solid, cost of pro- duction of ice by, 238 process, the, 7 Liquor ammonia, ordinary commer- cial price of, 113 strength of, 37, 38 London and Tilbury Lighterage Co., Ltd., refrigerated barges of, 186 Loose ground, freezing of, for well sinking, &c., 205 — 2o6d^ tools required in ice factoiy, 232 Loss by absorption of heat by am- monia gas after leaving the con- denser, 84 of pressure by friction of com- pressed air in pipes, 256 Losses by leakage of gas in com- pressors, 42, 51 in woiking ammonia absorption machines, 234 Lowe's carbon dioxide refrigerating machine, 34 Lubrication of ammonia compres- sors, 42, 54, 82, 89 Lucania, ss., cold stores on board of, 182, 183 Lugo and McPherson's cold-air machine, 128 see also Tuttle & Lugo MACHINE for refrigerating cold store or chamber, to esiimate capacity required, 175 distillation of methylic ether, 27 Mach, Dr. Ernst, on theory of heat, 4 ^74 INDEX. Machines for the distillation of water for ice-making purposes, 222, 227 Mackay & Christiansen's improved ammonia absorption machine, 94, 105 Mackay, F. N., refrigerating system, 150^' Management of ammonia compres- sion machines, 'j'j cold-air machines, 143 Marchant's cold-air machine, 117 Marine installations, suital ility of cold-air machines for, 142 Marine installation, cold-air pipe or trunk for, 173 general arrangement and stor- age of, 173 cold stores or chambers, i8r, 182, 183, 185, 186 Marriotte's law, 5 Martindale, Col. B. H,, description by, of refrigerating machinery at St. Katherine's Docks, 145 Mataura, refrigerating installation on beard of, 2 McPherson, see Lugo & McPherson Mean annual temperatures of prin- cipal cities of the world, 262 Meat, refrigerating machines for preserving, 161 Mechanical equivalent of heat, 3, 4 Melting of a solid, production of cold by, 7 cost of making ice by, 238 Memoranda, useful, 240 Mercury wells, 91 Metallic packing for stuffing boxes of ammonia compressors, 90 Methylic ether, 27 Milk, frozen, trade in, 2 Mirrlees, Watson, & Yaryan Co., Ltd., see Yaryan Mixtures, freezing, table of princi- pal, 10 Moisture, removal of, from air in cold-air machines, 132, 136, 137, 138 Molesworth, heat conducting power of various substances, 264 Monist, paper in, by Dr. Mach, 4 Mort, improved ammonia absorp- tion machine, 94, 10 1 see also Nicoili & Mort Muriate of lime, see chloride of calcium Mutton, frozen, proper method of hanging, 172 NAIRN, improvements in vacuum machines by, 13 Naphtha, use of, as a refrigerating agent, 31 Neubecker's ammonia compressor, 58 Niagara Hall, artificial ice at, 206 Nicoili & Mort's ammonia absorp- tion machine, 115 Non-conducting substances for in- sulating purposes, 163 choice of, 164 experiments "v\dth, 165, 166, 167, 169, 170, 171 covering for parts of am- monia compression appar- atus, 84 Nonpariel, refrigerating installation on board of, 2 OBJECTIONS to cold-air ma- chines, 137, 142 ether machines, 31 ammonia machines, 37 vacuum machines, 16 carbonic acid machines, 35 Obstructions in ammonia pipes, to remove, 88 cooling coils, to remove, 108 Oceana ss., refrigerating installation on board of, 2 October temperature, to obtain in brewery fermenting and yeast rooms, 193 Oil, presence of, in ammonia com- pression apparatus, 79 most suitable for use in am- monia compressors, 45, 46, Zz separators, 48, 69, 85, 86 Opacity of ice, reason for, 20S Open trough system of refrigera- tion, 1^7, 150 Ordway, Professor J. M., experi- ments by, with vaiious non-con- conducting substances, 170 INDEX. 275 Orgamc substances, preservation of, 151, i6r, 188 Orient ss., refrigerating installation on board of, 2 Orifices, coefficients for the efflux of air from, 257 Orosius, see Esthonian tribe PACKING carcasses in cold stores or chambers, 172 piston rod stuffing boxes of ammonia compressors, 89, 90 valve or stop-cock stuffing boxes, 70, 103 Paraffin oil, use of refrigerating ma- chinery in the manufacturt/ of, 188, 197 Passenger steamers, cold stores on board of, 181, 182 Peclet, table from experiments by showing non-conducting proper- ties of various materials, 165 Peninsular and Oriental Company's passenger steamers, cold stores or chambers on board of, 181 Perkins, Jacob, compression ma- chine of, 21 Photograph accessories, use of re- frigerating machinery in factories of, 204 Pictet, Raoul, experiments by, on radiation at low temperatures, 166 sulphurous acid machine, 31 ammonia compression machine, 67 cost of producing ice with ma- chines of, 237 improved refrigerator, 68 special refrigerating agents, 32, 114 Pieper, on working of Windhausen vacuum machine, 238 Pipes, friction of liquids in, 250 standard wrought iron, dimen- sions, &., of, 251 loss of pressure by friction of compressed air in, 256 Pipe joints, gas light, 70, 103, 108, 153 154, 155, 156 Piston rod of ammonia compressors, packing of, 89, 90 Plate or wall system of making clear ice, 209, 215 Pockets, see traps or pockets Pcetsch method of utilising refrige- rating machinery in the sinking of colliery shafts, 206 — 2c6<;7^ Pontifex, E. L., improved gas- tight joint for ammonia pipes, 108 ammonia absorption machine, 94, 106 Pontifex- Wood improved ice-box 01 tank on the wall or plate system, 215 cell ice-making tank or box, 219 ammonia absorption machines, cost of working, 234 apparatus for cooling water for attemperators in breweries, 189 brewery refrigerator, 193 arrangement of refrigerating machine, for an artificial but- ter works, 201 pyramidical crystal ice-making tank or box, 211 can ice-box, 212 Portable water distilling or de- aerating apparatus, 226 refrigerators, 185 Postle's cold- air machine, 118 Power required to drive centrifugal pumps, 249 Preserving unfrozen meat, &c., tem- perature of store for, 162, 258, 259 Pressure, excess condensing, 91 in ammonia machines, 40, 42, 90, 91, 92, 185 of water, 246 Price of ordinary commercial liquor ammonia, 113 Principal cities, mean annual tem- peratures of, 262 Production of cold by the rapid dissolution of a solid, 7, 238 Proper charge in ammonia com- pression machines, to ascertain, 78, 92 Properties of saturated ammonia gas, 242 of saturated steam, 260 276 INDEX. ProtoSy refrigerating installation on bo:.rd of, 2 Provisions, fresh, trade in, i injury to duiing transit, 3 damage to, by snow present in cold air, 141 Public buildings, cooling of, by means of refrigerating machinery, 206 Pulsometer Engineering Co., am- monia compression machines, 58, 63 cost of working, 236 carbonic anhydride machines, 35 cold store or chamber, 147 factory, 221 5 — 221^ portable refrigerators, 186 ice delivery machines, 231 improved ammonia compi es- sors, 58 Pumice as an insulating material, 163 Pumps, ammonia, 67, 105, 106, no of vacuum machines, 13, 14, IS, 16, 17, 18 Puplett, Samuel, improved ammonia compression apparatus, 68, 70 oil separator or interceptor, 69 water cooling apparatus, 84 agitators for making clear or crystal ice, 212 small cold store or chamber, 177 and Rigg's improved ammonia compression machine, 68 apparatus for lifting ice cans, 231 QUICKSAND soils, freezing of in well-sinking, &c.,205 — 206& RADIATION at low tempera- lures, experiments on, 166 Railway trucks and vans, refrigera- tion of, 186 Readings fiom instruments when testing ammonia compression in- stallation, number of requited, 90 Rectifiers, 99, 102, 104, 105 Reece, Rees, impioved ammonia absorption machine, 94, 98 Refrigerating mixtures, 9 machines, different classes of, 6 chamber on brine circulation system, 147 pipes, care of, 157 Refrigerators, 9, 23, 25, 28, 29, 31, 32, 40, 48, 66, 67, 68, 96, 100, 105, 183, 185, 186, 187 Refrigeration, 144 Regulating cocks for valves for am- monia machines, 70, 80, 107 ether machines, 29 Regulation of ammonia compres- sion machines, 79 Relieving of thawing tanks, 49, 212, 229 Rhigoline, use of, as a refrigerating agen% 31 Richardson, Dr. B. W., on the anti-putiescent qualities of am- monia, 151 Rigg, J. L., compression apparatus o', 68 Ri er Plata, supply of frozen mut- t n from, 2 Romans, method of cooling used by, 7 Roscoe, Sir H. E., on properties 01 carbonic acid or carbon dioxide, 35 Rossi, see De Motay & Rossi Rumford, Count, see Thompson, Benjamin SANTORIO, method of cooling wine mentioned by, 7 Saturated steam, properties of, 260 ammonia gas, properties of, 242 St. Clair's compound ammonia compressor, 75 St. Katherine's Docks, installation of refrigerating machinery in cold stores at, 145 plan adopted for the insulation of coM stores or chambers at, 172 INDEX. 277 Scientific definitions, misleading nature of, 3 Sealing oil for ammonia compres- sion machine, 42, 72 path taken by through com- plete apparatus, 48 Seeley's improved absorption ma- chine, 113 Separate air cooling compartment system, 159 Separators, 27, 31, 37, 48, 69, 85, 86, 114, 133, 136, 137, 138 Ships' holds, cooling of, 162 Siebe Gorman & Co., Harrison type of sulphuric ether machine made by, 25 Siemens, Sir W., machine for the production of cold by the lique- faction process, 8 cost of making ice with, 239 Slow freezing, manufacture of clear ice by, 209 Snow boxes, 137, 146, 173 Solubility of ammonia in water at different temperatures, 258 Southampton Docks, description of cold stores at, 159 Southby, see Blytb & Southby Specific heat, 3, 4 gravity of pure ice, 208 heat of ice, 208 Standard unit of heat, 3 Stanley, H. F., improved ammonia absorption machine, 94, 10 1 Stationary shallow cell system of making clear or crystal ice, 209, 210,218 Steam, exhaust, use of for ice mak- ing, 49, 222 saturated, properties of, 260 Steamers, see passenger steamers Sterne, L. & Co., Ltd., ammonia compression machinesmadeby,42 Stevenson & Co.'s cold-air machine, 137 Stewart, Balfour, definition by, of latent heat, 4 Stop-cocks or valves for ammonia apparatus, 70, 155, 156 See also regulating and expan- sion valves Storage rooms or chambers to esti- mate amount of refrigerating pipes for, 259 Stores or chambers, cold, insulation of, 163 Stuffing boxes of ammonia com- pression machines, 42, 54, 56, 58, 66, 79, 89, 90 pumps, 103, 106, no stop-cocks or valves, 70, 103 Sturgeon's cold-air machine, 137 Suction valves of ammonia com- pression machines, lift of, 82 Sugar factories, use of refrigerating machinery in, 204 Sulphide of carbon, use of as a re- frigerating agent, 114 Sulphur dioxide, see sulphurous acid Sulphuric ether, use of, as a refrige- rating agent, 25, 26 Sulphurous acid, use of, as a re- frigerating agent, 31, 114 method of manufacture, 31 anhydrous, 32 SuLzer engine, 57 TABLE of principal freezing mixtures, 10 giving results of tests carried out with an ether compres- sion machine, 30 of amounts of vapour condensed in various stages of cooling air, 133 giving results of tests made with an ammonia compres- sion machine, 57 giving results of tests made with cold-air machines, 143 giving non-conducting proper- ties of various substances, 165, 166, 168, 169, 171, 264 giving results of tests as to the relative and absolute thermal conductivities of various sub- stances, 168 giving results of tests as to the relative conductivities of asbestos and kieselguhr, 169 278 INDEX. Table giving loss of pressure by friction of compressed air in pipes, 256 giving results of experiments on the heat conductivities of various substances, 171 of evaporation of liquids, 240 of friction of air in tubes, 256 giving amounts of aqueous vapour held in suspension in air at di£ferent temperatures, 241 giving solubility of ammonia in water, 258 showing properties of saturated ammonia gas, 242 giving temperatures adapted tor cold stores for various articles, 258 giving comparison between Cent, and Fahr. thermometer scales, 243 giving properties of saturated steam, 260 giving comparison between various hydrometer scales, 244, 245 giving decimal equivalents of fractions of an inch, 262 giving pressure of water, 246 giving mean annual tempera- tures in principal cities, 262 of diameters, areas, and dis- placements, 247 giving power required to raise water from deep wells, 248 of heat-conducting powers of various substances, 264 giving quantity of water dis- ' charged by barrel pumps per minute, 248 giving proportions of supply and delivery pipes of hydrau- lic rams, 249 giving efficiency of hydraulic rams, 249 giving power required to drive centrifugal pumps, 249 of friction of Tquids in pipes, 250 giving dimensions, &c., of standarl wrought iron pipe, 251 Table giving comparison of British measures with U.S. standards, 251 Tancredus, Latinus, method of freezing water mentioned by, 7 Tellier, Charles, compresL-ion ma- chine of, 26, 28 apparatus for the distillation of methyhc ether, 27 and Pictet machines, cost of producing ice with, 237 Temperature exchanger or econo- miser for ammonia machines, 100, loi, no for cold-air machines, 132, 136 rise of, in cold or refrigerated air on passing through con- duits, 146 to regulate with ammonia com- pression machines, 79 Temperatures adapted for the cold storage of various articles, 258 mean annual, of principal cities, 262 Terms relating to heat, &c., ex- planation of, 3 Tests with ammonia compression machine, results of, 57 of exhausted liquor left in am- monia slill, 38 for efficiency of ammonia com- pression apparatus, 90 fittings required for, 90 of relative and absolute thermal conductivities of various sub- stances, 16-7 of water or brine for leakages of ammonia, 263 Thawing tanks, 49, 212, 229 Thermal unit of heat, 3 units in a ton of ice, 208 Thermometer scales, formula for conversion of, 242 table of comparison of, 243 Thomas, F. S., refrigerating system, Thompson, Benjamin (Count Rum- foid), theory of heat, 3 Tompkins, E. H,, improvements in ammonia absorption machines, 94. 105 Tools, loose, required in an ice fac- tory, 232 INDEX. 279 Toselli apparatus for maldnfj ice by the liquefaction process, 8 Trade in fresh provisions, short his- tory of, I Transparent crystal ice, method of making, 209 Traps or pockets for catching and carrying off water in rectifiers of absorption machine^; 102, 109, III, 112 Traversing carcasses through freez- ing chamber or room, 150 Trough, open, system of refrigera- tion by, 150 Truman, Hanbury & Co.'s brewery, first refrigerating machine used at, 188 Tubes, friction in, 256 Tunnelling in quicksand soils, use of refrigerating machinery for, 205 Tuttle & Lugo's cold-air machine, -128 Twining, Professor, compression machine of, 24 invention of plate or wall sys- tem of ice making by, 209 UNITED States standards, com- parison of British measures with, 251 Useful information, 251 tables and memoranda, 239 VACUUM process, 12 agent used, 20 making ice by, 15, 16, 229 mi chines, 13 — 19 cost of making ice with, 238 Vallance, improvements in vacuum machines by, 14 Valves, expansion, 29, 70, 80, 107 care of, 89 lift of, 82 Vapourisers, see Refrigerators Villafranca, Blasius, utilisation of liquefaction process by, for the production of cold, 7 Volatile refrigerating agents, ab- straction of heat by, 21 WALLS for cold chambers, various, 163, 164, 165, 172, 177, 182, 183 Wall or plate system of refrigera- tion by brine circulation, 149 of making clear crystal ice, 20f), objections to, 209, 217 advantages of, 218 Walker's apparatus, 9 Washing and freeing cold air from snow, 160 Water, common method of cooling in hot climates, 12 power required to raise from deep wells, 248 quantities of discharged per minute by barrel pumps, 248 presence of, in ammonia com- pression apparatus, 79 amount of, required for cooling purposes in jacket of am- monia compressor, 83 companies' mains, use of water from for condensm j purposes, 31, 83 condensing, amount of required in ether machines, 30, 31 ammonia compression ma- chines, 83 consumption of, in vacuum machines, 16 cooling and saving apparatus, 84 pockets or traps for absorption machine, 102, J09, 1 11, 112 containers for absorption ma- chines, 103 cost of cooling by means of an ammonia absorption machine, 234 eflfect of presence of, on heating or cooling of air, 138 pressure of, 246 iSo INDEX. Webb's patent valves, 66 Wells, mercury, for testing installa- tion on the ammonia compression system, 91 Well-sinking in quicksand soils, use of refrigerating machinery for, 205 West Indian fruit, fust cargo of brought to this country, 2 see Delia Beffa and West Weyde, Van der, compression re- frigerating apparatus of, 31 Whitelaw, see Johnson & White- law Windhausen's carbonic acid ma- chine, 32 compound vacuum pump, 14 compressor for treating the gas in two stages, 33 double-cylinder cold-air ma- chine, 119 single-cylinder cold-air ma- cMne, 122 Windhausen's vacuum machine, cost of producing ice with, 238 Wine growers and merchants, use of refrigerating machinery by, 204 Wood, see Pontifex & Wood Working of refrigerating machinery, cost of, 30, 57, 98, 113,233, 23 ^. 236 Worthington duplex pumps, esti- mating capacity of, 247 Wort-, beer, refrigerators or cooleis for, 191, 192, 193, 201 Wi ought-iron pipes, standard di- mensions, etc., of, 25 1 Y ARYAN water distilling appar- atus, 222, 224, 226 "Yeast rooms, cooling air in, 193 PRINTED BY J. S. VIRTUE AND CO., LIMUED, ClIY ROAD, LONDON. Station Kits' Hall Court, London, EXl. September, 1896. CATALOGUE OF BOOKS INCLUDING NEW AND STANDARD WORKS IN ENGINEERING: CIVIL, MECHANICAL, AND MARINE; ELECTRICITY AND ELECTRICAL ENGINEERING; MINING, METALLURGY; ARCHITECTURE, BUILDING, INDUSTRIAL AND DECORATIVE ARTS; SCIENCE, TRADE AND MANUFACTURES; AGRICULTURE, FARMING, GARDENING ; AUCTIONEERING, VALUING AND ESTATE AGENCY; LAW AND MISCELLANEOUS. PUBLISHED BY CROSBY LOCKWOOD & SON. MECHANICA L ENGINEER ING, etc. i ». K. CRark's Pocket-Book for Mechanical Engineers. THE MECHANICAL ENGINEER'S POCKET-BOOK OF TABLES, FORMULM, RULES AND DATA. A Handy Book of Reference for Daily Use in Engineering Practice. By D. Kinnear Clark, M.Inst.C.E., Author of " Railway Mactimery," " Tramways," &c. Third Edition, Re- vised, Small 8vo, 700 pages, 6s. bound in flexible leather cover, rounded corners. Summary of Contents. Mathematical Tables. — Measurement of Surfaces and Solids.^" -fiNGLisH Weights and Measures.— French Metric Weights and Mea- ■suRES.— Foreign Weights and Measures.— Moneys.— Specific Gravity, weight and Volume. — Manufactured Metals.— Steel Pipes.— Bolts and Nuts. — Sundry Articles in Wrought and Cast Iron, Copper, Brass, Lead, Tin, Zinc. — Strength of Materials. — Strength of Timber. — Strength of Cast Iron. — Strength of Wrought Iron. — Strength of Steel. — Tensile Strength of Copper, Lead, etc. — Resistance of Stones and other Build- ing Materials. — Riveted Joints in Boiler Plates. — Boiler Shells — Wire Ropes and Hemp Ropes. — Chains and Chain Cables. — Framing. — Hardness OF Metals, Alloys and Stones. — Labour of Animals. — Mechanical Prin.= ciples.— Gravity and Fall of Bodies.— Accelerating and Retarding Forces. — Mill Gearing, Shafting, etc. — Transmission of Motive Power.— Heat. — Combustion: Fuels. — Warming, Ventilation, Cooking Stoves. -^ Steam. — Steam Engines and Boilers. — Railways. — Tramways. — SteajiS Ships. — Pumping Steam Engines and Pumps. — Coal Gas, Gas Engines, etc. — Air in Motion.— Compressed Air.— Hot Air Engines.— Water Powfr-=> Speed of Cutting Tools.— Colours.— Electrical Engineering. %* Opinions of the Press. " Mr ClarK manifests what is an innate perception ot what is likely to be use*'ul hi a pocKei- ■Dook, and he is really unrivalled in the art ot" condensation. Very frequently we find the informa- tijn on a given subject is supplied by giving a summary description of an experiment, and a state- ment of the results obtained. There is a very excellent steam table, occupying five and-a-balf oages ; and there are rules given for several calculations, which rules cannot be found in other pocket-books, as, for example, that on page 497, for getting at the quantity of water in the shape of priming in any k.iown weight of steam. It is very difficult to hit upon any mechanical engineer- tn J' subject concerning which this work supplieb no information, and the excellent index at the end a ids to its utility. In one word, it is an exceedingly handy and efficient tool, possessed of whicli tne engineer will be saved many a wearisome calculation, or yet more wearisome hunt through •s-^rious text-books and treatises, and, as su:h, we can heartily recommend it to our readers^ who must not run away with the idea that Mr. Clark's Pocket-book is only Molesworth in another 6onn. On the contrary, each contains what is not to be found in the other ; and Mr. Clark takes tiiOre room and deals at more length witii many subjects than Molesworth possibly could." The Engineer. " It would be found difficult to compress more matter within a similar compass, or produce a book of 650 pages which should be more compact or convenient for pocket reference. . Will be appreciated by mechnaical engineers of all classes."— Prarfzca/ Engineer. " Ju'st the kind of work that oractical men require to have near to them."- English Mechanic, CROSFiY LOCKWOOD &• SON'S CATALOGUE. MR. HUUON'S PnACTICAL HANDBOOKS. Handhooh for Works' Managers, THE WORKS' MANAGER'S HANDBOOK OF MODERN RULES, TABLES, AND DATA. For Engineers, Millwrights, and Boiler Makers; Tool Makers, Machinists, and Metal Workers; Iron and brass Founders, &c. By W. S. Hutton, Civil and Mechanical Engineer, Author of "The Practical Engineer's Handbook." Fifth Edition, caretuUy Re- vised, with Additions. In One handsome Volume, medium 8vo, pr^c^ i.qs. strongly bound. [J^'^i published. fca*" The Author having compiled Rules and Data fay his own. use in u ^rcu-t variety of modern engineevins; work, and having found his notes extremely useful, decided to publish them— revised to date — believing that a practical work, suited to r/te DAILY REQUIREMENTS OF MODERN ENGINEERS, would be favourably received. In the Fourth Edition the First Section has been re-written and improved by the addition of numerous Illustrations and new matte-/ relating to Steam Engines and Gas Engines. The Second. Section ha^ been enlarged and Illustrated, and through- out the book a great number of emendations and alterations have been made, with the object of rendering the book more generally useful. %* Opinions of the Press. "The author treats every subject from the point of view of one who has collected workshop notes for application in ■workshop cract«'>", rather tlian from the theoretical or literary aspect. The volume contains a great deal of tnat kiuj uf information which is gained only by practical experi- ence, and is seldom written in books." — Engineer, "The volume is an exceedingly useiul one, brimfui with engineers' notes, memoranda, and rules, and well worthy of being on every mechanical engineer's bookshelf." — Mec'-ianical World. " The information is precisely that likely to be required in practice. . . . Tae work forms a desirable addition to the library not only of the works' manager, but of anyone connected with general engineering." — Mtniiig Joicrnal. "A formidable mass of facts and figures, readily accessible through an elaborate Index . . . Such a volume will be found absolutely necessarv- as a book of reference in a'J sorts ef '"works' connected with the metal trades."— Xyland's iron Trades Circular. " Brimful of useful information, stated in a concise iorm, Mr. Hutton's books have met a press- ip_n- want among engineers. The book must prove extremely useful to every practical mas possessing a copy." — Practical Engineer, New Manual for JPractical Engineers, THE PRACTICAL ENGINEER'S HAND-BOOK. Comprising a Treatise on Modern Engines and Boilers : Marine, Locomotive and Sta- tionary. And containing a large collection of Rules and Practical Data relating to recent Practice in Designing and Constructing all kinds of Engines, Boilers, and other Engineering work. The whole constituting a comprehensive Key to the Board of Trade and other Examinations tor Certi- ficates of Competency in Modern Mechanical Engineering. By Walter S. Hutton, Civil and Mechanical Engineer, Author of "The Works' Manager's Handbook for Engineers," &c. With upwards of 370 Illustrations. Fifth Edition, Revised, with Additions. Medium 8vo, nearly 500 pp., price tS'. Strongly bound. [7"^^ published, IS" This work is designed as a companion to the Author's " Works' Manager's Hand-book." It possesses many new and originaJ features, and con- tains, like its predecessor, a quantity of matter not originally intended for publica- tion, but collected by the author for his own use in the construction of a great variety 0/ Modern Engineering Work. The information is given in a condensed and concise form, and is illustrated by upwards of 570 Woodcuts; and comprises a quantity of tabulated maiter of great value to all engaged in designing, constructing, or estimating for Engines, Boilers. and OTHER Engineering Work. %* Opinions of the Press. " We have wept It at hand for several weeks, referring to it as occasion arose, tind we have not on a Single occasion consulted its pages without finding the information of which we were in quest ' — A(hent^uf/t. " A thoroughly good practical handbook, which no engineer can go througli without leamiisg something that willbe of service to him." — Marine Engineer. " An excellent book of reference for engineers, and a vciluable text-book for students 01 engineering." — Sf,'is//tan. "This valuable manual embodies the results and experience of the leading authorities on mechanical engineering. " — Building A^ezcs. •• The author has collected together a surprising quantity of rules and practical data, and has snown much judgment in the selections he has made. . . . There is no doubt that this book is one of the most useful of its kind published, and will be a very popular compendium." — Engineer. " A mass of information, set down in simple language, and in such a form that it can be eas^ referred to at any time. The matter is uniformly good and well chosen and is greatly elucidated bj' the illustrations. The book will find its way on to most esgineers' she'ves. whe^e it will rank as one of the most useful books of reference." — Practical Engineer. " Full of useful information and should be found on the office shelf of all practical engineers. —English Mechanic. MECHANICAL ENGINEERING, etc. MR. MUTTON'S PRACTICAL HANDBOOKS— continued. Practical Treatise on 3Iodern Steam-Boilers, STEAM-BOILER CONSTRUCTION. A Practical Handbook tor Engineers, Boiler-Makers, and Steam Users. Containing a large Col- lection of Rules and Data relating to Recent Practice in the Design, Con- struction, and Working of all Kinds of Stationary, Locomotive, and Marine Steam-Boilers. By Walter S. Hutton, Civil and Mechanical Engineei, Author of "The Works' Manager's Handbook," "The Practical Engineer's Handbook," &c. With upwards of 300 Illustrations. Second Edition. Medium 8vo, iSs. cloth. PS" This work is issued in continuation of the Scries of Handbooks written by the Author, viz; — "The Works' Manager's Handbook'' ant/ "The Practi- cal Engineer's Handbook," w/u'c/i are so highly appreciated by Engineers for the practical nature of their information ; and is consequently written in the same style as those works. The Author believes that the concentration, in a convenient form for easy refer- ence, of such a large amount of thoroughly practical information on Steam-Boilers, will be of considerable service to those for whom it is intended, and he trusts the book may be deemed worthy of as favourable a reception as has been accorded to its predecessors. _ *** Opinions of the Press. "iivery detail, both In boiler design and management, is clearly laid before the reader. Tfce volume shows that boiler construction has been reduced to the condition of one of the most exait sciences ; and such a book is of the utmost value to the /in de siecle Engineer and Works' Manager. " — Marine Engineer. " There has long been room for a modem handbook on steam boilers ; there is not that rooni now, because Mr. Hutton has filled it. It is a thoroughly practical boolc for those who are occu- pied in the construction, design, selection, or use of boUers. " — Engineer. " The book is of so important and comprehensive a character that it must find Its way into the libraries of everyone interested in boiler using or boiler manufacture if they wish to be thoroughly informed. We strongly recommend the bock for the intrinsic value of its contents.'' — Mackiyiery Market. " The value of this book can hardly be over-estimated The author's rules, formulae &c., ate all very fresh, and it is impossible to turn to the work and not find what you Wcint. No practical engineer should be without it." — Colliery Guardian. Hutton's ** Modernised Temjyleton*" THE PRACTICAL MECHANICS' WORKSHOP COM- PA NION. Comprising a great variety of the most useful Rules and Formulae in Mechanical Science, with numerous Tables of Practical Data and Calcu- lated Results for Facilitating Mechanical Operations. By William Temple- TON, Author of "The Engineer's Practical Assistant," &c. &c. Seventeenth Edition, Revised, Modernised, and considerably Enlarged by Walter S. Hutton, C.E., Author of "The Works' Manager's Handbook," "The Practical Engineer's Handbook," &c. Fcap. 8vo, nearly 500 pp., with 8 Plates and upwards of 250 Illustrative Diagram-s, 6s., strongly bound for workshop or pocket wear and tear. *^* Opinions of the Press. '• in Its modernised form Hutton's ' Templeton 'should have a wide sale, for It contains mm h caluabie informanon which the mechanic will often find of use, and not a few tables and notes whicL he might look for in vain in other works. This modernised edition will be appreciated by ail who have learned to value the original editions of Templeton.' ' — E7iglish. Mechanic. " It has met with great success in the engineering workshop, as we can testify ; and there are 3 great many men who, in a great measure, owe their rise in life to this little book. ' — Building New^. " This familiar text-book — well known to all mechanics and engineers— is of essential service to the ever}--day requirements of engineers, millwrights, and the various trades connected with engineering and building. The new modernised edition is worth its weight in gold." — Building I^eTvs. (Second Notice.) " This well-known and largely-used book contains information, brought up to date, of the sort so useful to the foreman and draughtsman. So much fresh information has been introduced as to constitute it practically a new^ book. It will be largely used in the ofice and workshop."— Mechanical IVorld. " The publishers •s\-isely entrusted the task of revision of this popular, valuable, and useful book to Mr. Hutton, thin whom a more competent man they could not have found."— /ri?yt. Teinpletoa's Engineer's and Machinist's Assistant. THE ENGINEER'S, MILLWRIGHT'S, and MACHINIST'S PRACTICAL ASSISTANT. A collection of Useful Tables, Rules and Data. By William Templeton. 7th Edition, with Additions. i8mo, 2S, 6d. cloth. "^j^* Opinions of the Press. " Occuplis a forenost place among books of this kind. A more suitable present to an appren- tice to any of the mechanical trades could not possibly be made." — Building Neuis. " A deservedly popular work. It should be in the ' drawer ' of every mechanic"— jEw^'/trA Mechanic. 4 CROSBY LOCK WOOD S- SON'S CATALOGUE. Foley's Office Meference Book for Mechanical Engineers, THE MECHANICAL ENGINEER'S REFERENCE BOOK, for Machine and Boiler Construction. In Two Parts. Part I. Generai, Engineering Data. Part II. Boiler Construction. With 51 Plates and numerous Illustrations. By Nelson Foley. M.I.N. A. Second Edition, Revised throughout and much Enlarged. Folio, £3 5s. net half-HoTirH Summary of Contents. ^^'''^ published. PART I. Measures.— Circumferences and Areas, &c., Squares, Cubes, Fourth Powers. — Square and Cube Roots. — Surface of Tubes — Reciprocals. — Logarithms. — Mensuration. — Spe- cific Gravities and Weights. — Work and Power.— Heat.— Combus- tion.— Expansion AND Contraction. — Expansion of Gases.— Steam.— Static Forces.— Gravitation and Attraction. — Motion and Computa- tion of Resulting Forces.— Accu- mulated Work.— Centre and Radius of Gyration. — Moment of Inertia. — Centre of Oscillation.— Elec- tricity. — Strength of Materials. — Elasticity. — Test Sheets op Metals.— Friction. — Transmission of Pov.-er. — Flow of Liquids. — Flo%v of Gases. — Air Pumps, Surface Con- densers, &c. — Speed of Steamships. —Propellers — Cutting Tools. — Flanges. — Copper Sheets and Tubes.— Screws, Nuts, Bolt Heads, &c.— Various Recipes and Miscel- laneous Matter. With DIAGRAMS for Valve-Gear, Belting and Ropes, Discharge and Suction Pipes, Screw Propellers, and Copper Pipes. PART II. Treating OF, Power OF Boilers. — Riveting. — Boiler Setting, Chim- UsEFUL Ratios. — Notes on Con- ' neys, and Mountings. — Fuels, &c. — STRUCTioN. — Cylindrical Boiler j Examples of Boilers and Speeds op Shells. — Circular Furnaces. — j Steamships. — Nominal and Normal Flat Plates. — Stays. — Girders. — 1 Horse Power. Screws. — Hydraulic Tests. — ' With DIAGRAMS for all Boiler Calculations and Drawings of many Varieties of Boilers. *^'^ Opinions of the Press. " The book is one -n-liich every mechanical engineer may, with ad-s^-ntage to himself add to his librarj-." — Indtistries. " Mr. Foley is well firted to compile such a work. . . . The diagrams are a great feature oftheiTork. . . . Regarding the v.-hole work, it may be verj- fairlj- stated that Mr. Folej- has produced a volume which v.ili undoubtedly fulfil the desire of the author and become indispen- sable to all mechanical engineers."— ^''arijze E7tgi7ieer. " We have carefully examined this work, and pronounce it a most excellent reference book for the use of marine engineers." — J-oi'.T7ial of Atnerican Society of Ka-val hngineers. " A veritable monument of industrj' on the part of Mr. Foley, who has succeeded in producing what is simply invaluable to the engineering profession."— i"/M?«i-/ji*. Coal and Speed Tables. A POCKET BOOK OF COAL AND SPEED TABLES, for Engineers and Steam-users. By Nelson Foley, Author of "The Mechanical Engineer's Reference Book " Pocket-size, 3s. 6d. cloth. "These tables are designed to meet the requirements of everj'-day use ; they are of suffi- cient scope for most practical purposes, and may be commended to engineers and users of steam ?' — Iron. " This pocke:-book well merits the attention of the practical engineer. Mr. Foley has com- piled a verj' usetul set of tables, the information contained in which is frequently required by engineers, coal consumers emd users of steam."— Iron and Coal Trades Review. Steam Engine, TEXT-BOOK ON THE STEAM ENGINE. With a Sup- plement on Gas Engines, and Part II. on Heat Engines. By T. M. Goodeve, M.A., Barrister-at-Law, Professor of Mechanics at the Royalt College of Science, London; Author of "The Principles of Mechanics," "The Elements of Mechanism," &c. Twelfth Edition, Enlarged. With nu- merous Illustracions. Crown Svo, 6s. cloth. " Professor Goodeve has given us a treatise on the steam engine which will bear comparison •Bath anj'thing written by Huxley or IMaxwell, and we can award it no higher praise." — En^riftetr " Mr. Goodeve's text-book is a work of which Ofery young engineer should possess himself. — Mininsr Journal. MECHANICAL ENGINEERING, etc. ON GAS-ENGINES. With Appendix describing a Recent Engine with Tube Igniter. By T. M. Goodeve, M.A. Crown 8vo, as. 6d. cloth. [Just published, " Like all Mr. Goodeves writings, the present Is no exception In point of general excellence It Is a valuable little volume." — Mechatiical World, Steam Engine Design. A HANDBOOK ON I HE STEAM ENGINE, with especial Reference to Small and Medium-sized Engines. For the Use of Engine- Makers, Mechanical Draughtsmen, Engineering Students and Users of Steam Power. By Herman Haeder, C.E. English Edition, Re-edited by the Author from the Second German Edition, and Translated, with considerable Additions and Alterations, by H. H. P. Powles, A.M.I.C.E., M.I.M.E. With nearly i,ioo Illustrations. Crown 8vo, gs. cloth. " A perfect encyclopedia of the steam engine and its details, and one which must take a per- manent place in Engl'sh drawing-offices and workshops." — ^ Forema)i Palterji-makej'. "This is an excellent book, and should be in the hands of all who are interested in the con- struction and design of medium-sized stationary engines. ... A careful study of its contents and the arrangement of the sections leads to the conclusion that there is probably no other book like it in this country. The volume aims at showing the results of practical experience, and it certainly may claim a complete achievement of this idea." — Nature. " There can be no question as to its value. We cordially commend it to all concerned in the design and construction of the steam engine." — Mecha7tical World. Steam Boilers. A TREATISE ON STEAM BOILERS: Their Strength, Con- itruction, and Economical Working. By Robert Wilson, C.E. Fifth Edition. izmo, 6s. cloth. "The best treatise that has ever been published on steam boilers." — Engineer. "The author shows himself perfect master of his subject, and we heartily recommend all em- ploying steam power to possess themselves of the wotk."—Ry land's Iron Trade Circular. Boiler Chimneys. BOILER AND FACTORY CHIMNEYS; Their Draiight-Powet and Stability, With a Chapter on Lightning Conductors. By Robert Wilson, A. I. C.E. , Author of "A Treatise on Steam Boilers," &c. Second Edition. Crown 8vo, 2,s. 6d. cloth. " A valuable contribution to the literature of scientific building." — T^e Builder, Boiler Making, THE BOILER-MAKER'S READY RECKONER S- ASSIST- A NT. With Examples of Practical Geometry and Templating, for the Use of Platers, Smiths and Riveters. By John Courtney, Edited by D. K. Clark, M.I. C.E. Third Edition, 480 pp., with i40lllusts. Fcap. 8vo, ys. half-bound, " No workman or apprentice should be without this hook."— iron Ttade Circular. Locomotive Engine Developjnent. THE LOCOMOTIVE ENGINE AND ITS DEVELOPMENT. A Popular Treatise on the Gradual Improvements made in Railway Engines between 1803 and 1896. By Clement E. Stretton, C,E., Author of " Safe Railway Working," &c. Fifth Edition, Revised and Enlarged. With 120 Illustrations. Crown 8vo, 3s. 6rf. cloth gilt. [Just pubhshtd. " Students of railway history and all who are interested in the evolution of the modern locomo- tive will find much to attract and entertain in this volume." — T/te Times. " The author of this work is well known to the railway world, and no one probably has a better knowledge of the history and development of the locomotive. The volume before us should be of value to all connected with the railway system of this country." — Nature. Esti^nating for Engineering Work, <&c. ENGINEERING ESTIMATES, COSTS AND ACCOUNTS: A Guide to Commercial Engineering. With numerous Examples of Esti- mates and Costs of Millwright Work, Miscellaneous Productions, Steam Engines and Steam Boilers ; and a Section on the Preparation of Costs Accounts. By A General Manager. Demy 8vo, 12s. cloth. •' This is an excellent and very useful book, covering subject-matter in constant requisition to every factory and workshop. . . . The book is invaluable, not only to the young engineer, but also to the estimate department of every ■woT'ks."^Builder. " We accord the work unqualified praise. The information is given in a plain, straightforward manner, and bears throughout evidence of the intimate practicail acquaintance of the author with every phase of commercial engineering." — Mechanical World. CROSBY LOCK WOOD &- SON'S CATALOGUE. Fire Engineering, FIRES, FIRE-ENGINES, AND FIRE-BRIGADES. With a History of Fire-Engines, their Construction, Use, and Management; Re- marks on Fire-Proof Buildings, and the Preservation of Life' from Fire ; Statistics of the Fire Appliances in English Towns ; Foreign Fire Systems ; Hints on Fire- Brigades, &c. &c. By Charles F. T. Young, CE. Witb numerous Illustrations, 544 pp., deniy 8vo, £1 4s. cloth. " To those interested in the subject of fires and fire apparatus, we most heartily commend this l>ook. It is the only English work we now have upon the subject.' — Engineiring. Boilermakin g, PLATING AND BOILERMAKING : A Practical Handbook for Workshop Operations. By Joseph G. Horner, A.M.I.M.E. (Foreman Pattern-Maker), Author of " Pattern Making,'' &c. 380 pages, with 338 Illustrations. Crown 8vo, yi. 6d. cloth. {J'ust published. " The latest production from the pen of this writer is characterised by that evidence of close acquaintance with workshop methods which will render the book exceedinglj- acceptable to the practical hand. We have no hesitation in commending the work as a serviceable and practical handbook on a subject which has not hitherto received much attention from those qualified to deal with it in a satisfactorj- manRer." — Mechanical Woi-ld. Engineei^ng Construction, PATTERN-MAKING : A Practical Treatise, embracing the Main Types of Engineering Construction, and including Gearing, both Hand and Machine made, Engine Work, Sheaves and Pulleys, Pipes and Columns, Screws, Machine Parts, Pumps and Cocks, the Moulding of Patterns in Loam and Greensand, &c., together with the methods of Estimating the weight of Castings; to which is added an Appendix of Tables for Workshop Reference. By Joseph G. Horxer, A.M.l.M.E. (Foreman Pattern-Maker). Second Edition, thoroughly Revised and much Enlarged. With upwards ot 450 Illustrations. _ Crown 8vo, ys. 6d. cloth. [Jtist published. " A well- written technical guide, evidently written by a man who understands and has prac- tised what he has written about. . . . We cordiaUj^ recommend it to engineering students, j"oung journeymen, and others desirous of being initiated into the mysteries of pattern-making." — Builder. "More than 450 illustrations help to explain the text, which is, however, always clear and ex- piicit, thus rendering the work an excellent vadi iriicum for the apprentice who desires to become master of his trade." — English Mechanic. JHctionary of Mechanical Engineering Terms, LOCKWOOD'S DICTIONARY OF TERMS USED IN THE PRACTICE OF MECHANICAL ENGINEERING, embracing those current in the Drawing Office, Pattern Shop, Foundry, Fitting, Turning, Smith's and Boiler Shops, &c. &c. Comprising upwards of 6,000 Defin-itions. Edited by Joseph G. Horner, A.M.l.M.E. (Foreman Pattern-Maker), Author of " Pat- tern Making." Second Edition, Revised, Crown 8vo, ys. 6d. cloth, "Just the sort of handy dictionary required by the various trades engaged in mechanical en- gineering. The practical e'ngineering pupil will find the book of great value in his studies, and every forem.an engineer and mechanic should have a copy." — B-aiuii^ig- XeTvs. " Not merely a dictionary, but, to a certain extent, also a most valuable guide. It strikes us as a happy idea to combine with a definition of the phrEise useful information on the subject of which it tieBits."— Machinery Market, Mill Gearing, TOOTHED GEARING : A Practical Handbook for Offices and Workshops. By Joseph G. Horner, A.M.l.M.E. (Foreman Pattern-Maker), Author of "Pattern Making," &c, With 184 Illustrations. Crown 8vo, 6s. cloth. [Just published. Summary of Contents, Chap. I. Principles.— II. Forma- i Skew Bevels.— XII, Variable and TiON OF Tooth Profiles.— III. Pro- I other Gears. — XIII. Diametrical portions of Teeth.— IV, Methods i Pitch.— XIV. The Odontogkaph.— OF Making Tooth Forms.— V. Invo- I XV. Pattern Gears.— XVI. Machine LUTE Teeth.— VI. Some Special j Moulding Gears.— XVII. Machine Tooth Forms.— VII. Bevel Wheels. Cut Gears.— XVIII. Proportion of — VIII. Screw Gears. — IX. Worm ' Wheels. Gears.— X. Helical Wheels. — XI. 1 " We must give the book our unqualified praise for Its thoroughness of treatment, and we can heartily recommend it to all interested as the most practical book on the subject yet written.' — Mechanical M''orld. MECHANICAL ENGINEERING, etc. Stone- ivorfci7ig JHucMfiery. STONE-WORKING MACHINERY, and the Rapid and Economi- cal CcHversion of Stone. With Hints on the Arrangement and Managemeai oi Stone Works. By M. Fowis Bale, M.I M.E. With Illusts. Crown «vo, gs, "The book should be in the hands of every irason or student of stone-work."— Co//»«»-> Guardian. " A capital handbook fcr all who manipulate stone for building or ornamental purposes. -'--~ Machinery Marktt, Pu7Hp Construction and Management, PUMPS AND PUMPING : A Handbook for Pump Users. Being Notes on Selection, Construction and Management. By M. Powis Balk, M.I. M.E. , Author ot " Woodworking Machirery," " Saw Mills," &c. Second Edition, Revised. Crown 8vo, as. 6d. cloih. "The matter is set forth as concisely a^ possible. In fact, concen^ar.on rather than diffusene^S Has been the iuthor s aim throughout; yet he does not seem to have omitted anything likely to be of use." — •j-ounial cf Gas Lighting. " Thoroughly practical and simply and clearly written." — Glasgow Herald, Milling Machinery , etc. MILLING MACHINES AND PROCESSES: A Practical Treatise en Shaping Metals by Rotary Cutters, including Information on Making and Grinding the Cutters. By Paul N. Hasluck, Author of" Lathe- work," " Kandybooks for Handicrafts," &c. With upwards of 300 Engrav- ings, including numerous Drawings by the Author. Large crown 8vo, 35a pages, I2S. 6d. cloth. 'A new departure in engineering literatuie. . . . We can recommend this work to ^ Interested rmilling machines ; it is what it professes to be— a practical txea.t\se."— Engineer. " A capital and reliable book, which will no doubt be of considerable service, both to tbosa who are already acquainted with the process as well as to those v/ho contemplate its adoption." Ittdttstries Turning, LATHE-WORK : A Practical Treatise on the Tools, Appliances, and Processes employed in the Art of Tttyrang, By Paul. N, Hasluck, Fifth Edition, Revised and Enlarged Cr. 8vo, 5s. cloth. " Written by a man who knows, not only how work ought to bs done, but who also knows iicvr to do it, and how to convey his knowledge to others. To all turners this book would be valuable. — Engineering. " We can safely recommend the work to young engineers. To the amateur it will simply be invaluable. To the student it will convey a great deal of useful information," — Ensineer, Screw-Cutting. SCREW THREADS : And Methods oj Producing Them. With Numerous Tables, and complete directions for using Screw-Cutting Lathes. By Paul N. Hasluck, Author of " Lathe- Work," &c. With Sevsnty-fou4 Illustrations. Third Edition, Revised and Enlarged. Waistcoat-pocket size, IS. 6rf. cloth. " Full of useful information, hints and practical criticism. Taps, dies and screwing-tools gene- rally are illustrated and their action described." — Mechanical IVorld. " It is a complete compendium of aU the details of the screw-cutting lathe ; in fact a tnultum in parvo on all the subjects it treats upon." — Carpenter and Builder, Smith's Tables for Mechanics, etc, TABLES, MEMORANDA, AND CALCULATED RESULTS, FOR MECHANICS, ENGINEERS, ARCHITECTS, BUILDERS, etc. Selected andArranged by Francis Smith. Sixth Edition, Revised, including Electrical Tables, FoRMULiE, and Memoranda, Waistcoat-pocket size, IS. 6d. limp leather, [/»sf published^ " It would, perhaps, be as difficult to make a small pocket-book selection ot notes ana formiiisB to suit ALL engineers as it would bo •'O make a universEil medicine ; but Mr. Smith's waistcoat- pocket collection may be looked upoa as a successful attempt." — Efigineer. "The best example we have ever seen of 270 pages of useful matter packed into the dimea- sions of a cz.xd-czse."— Building News. "A veritable pocket treasury of knowledge."— /ytw. French- English Glossary for JCngineers, etc, A POCKET GLOSSARY of TECHNICAL TERMS: ENGLISH- FRENCH, FRENCH-ENGLISH ; with Tables suitable for the Architectural, Engineering, Manufacturing and Nautical Professions, By John Jame-s Fletcher, Engineer and Surveyor. Second Edition, Revised and Enlarged, 200 pp. Waistcoat-pocket size, is. 6d, limp leather. " It is a very great advantage for readers and correspondents in France and Fngland to have so large a number of the words relating to engineering and m.anufacf.urers collected in a hlliputian Tolume. The Uttle book will be useful both to students and travellers." — Architect. *' The glossary of terms is very complete, and many of the tables are new and well arranged. We cordially commend the hook."— M^hanieal World, CROSBY LOCK WOOD &> SON'S CATALOGUE. Tear-Hook of J^Hyinetiimj FormuUe, etc. THE ENGINEER'S YEAR-bOOK FOR 1896. Comprising Formulae, Rules, Tables, Data and Memoranda in Civil, Mechanical, Elec- tiical, Marine and Mine Engineering. By H. R. Kempe, A.M. Inst.C.E., M.I.E.E., Technical Cfficer of ihe Engineer-in-Chiet' s Office, General Post Office, London. Author of "A Handbook of Electrical Testing," "The Electrical Engmeer's Pocket- Book," &c V\i.h £00 Illustrations, specially Engraved for the work. Crown 8vo, 670 pages, 8s. leather. [Just published. " Represents an enormous quantitj' of work and forms a desirable book of reference." — The Enghieer. " The book is distinctly in advance of most simi'ar p'-blcations in this co^rwry ." — Engineering. •' Tnis valuable and well-designed book of reference meets the aemarids oi all descriptions of engineers. —5a/«r' Re-v:eTu. "Teems with up-to-date in'ormation in everj- branch of engineering and construction." — Building XcTvs. _ • " The needs ot the engineering profession could hardly be supplied in a more admirable, Cftniplete and convenient form. To say that it Uiore than sustains ah comparisons is praise ol the highest sort, ai d that may justly be said of it ' ^X aiuig jfcmriiai. " There is certainly room 'or the new comer, which supplies explanations and directions, as well as formute and tables. It deserves to become one of the most successful of the technical amuals. ' '—A rch itect. •■ Brinj^s together with great skiU all the technical information which an engineer has to use fey by day. It is in every wa}' adrairablj- equipped, and is sure to prove successfuL" — Scotsman. " The up-to dateness of Mr. Kempe's compilation is a quality that wiU not be lost on the busy people for whom the work is intended." — CasgoTv Herald. Portable Engines, IHE PORTABLE ENGINE; ITS CONSTRUCTION AND MANAGEMENT, A Practical Manual for Owners and Users of Steam Engines generally. By William Dyson Wansbrough. With 90 Illustra- tions. Crown 8vo, 35. 6d. cloth. " This is a work ot value to those who use steam machinery. . . . Should be read by every- oae who has a steam engine, on a farm or elsewhere." — Mark Lane Express. " We cordially commend this work to bujers and owners oi steam engines, and to those who have to do with their construction or use." — Timber Traaes jo-ur-nal. "Such a general knowledge of the steam engine as Mr. Wansbrough lumishes to the reader saould be acquired by all intelligent owners and others who use the steam engine. "—Building Nnus. " An excellent text-book of this useful form of engine. ' The Hints to Purchasers ' contain a 20oi deal of -ommonsense and practical wisdom." — E7iglish Mechanic. iron and Steel, ''IRON AND STEEL " ; A Work for the Forge, Founary, Factory, and Office. Containing ready, useful, and trustworthy Information for Iron- masters and their Stock-takers; Managers of Bar, Rail, Plate, and Sheet Rolling Mills ; Iron and Metal Founders; Iron Ship and Bridge Builders ; Mechanical, Mining, and Consulting Engineers ; Architects. Concractors, Builders, and Professional Draughtsmen. By Charles Hoare, Author of "The Slide Rule," &c. Ninth Edition, szmo. 6s. leather. "For comprehensiveness the book has not its equal.''— Iron. " One of the best of the pocket books." — Engiisli Mechanic. "We cordially recommend this book to those engaged in considering the details or all kinds of >on and steel works. " — Naval Science. Elementary 3Iechanics. CONDENSED MECHANICS. A Selection of Formulae, Rules, Tables, and Data for the Use of Engineering Students, Science Classes, &c. In Accordance with the Requirements of the Science and Art Department. By W. G. Crawford Hughes, A.M.I.C.E. Crown hvo, 25 td. cloth. •■' The book is well fitted for those who are either confronted with practical problems in their fTork, or are preparing for examination and wish to refresh their knowledge by going through their formulae again.'' — Marine EngiJieer. " It is well arranged, and meets the wants of those for whom it is intended."— ^ajV7fa> News, 3teafn. THE SAFE USE OF STEaM. Containing Rules tor Ud- professional Steam-users. By an Engineer. Seventh Edition. Sewed, 6d. " If steam-users would but learn this little book by heart, boiler explosions would beet me Jensations by their rarity." — English Mechanic. n arininij, HEATING BY HOT WATER; with Intormation and Sug- gestions on the best Methods of Heating Public, Private and Horticultural Buildings By Walter Jones. Second Edition. With 96 lUustrati )ns. Crown 8vo, 2s. 6d. net. " We confidently recommend all Interested In heating by hot water to secnre a copy ol tuis valuable little treatise." — The Plutnber and Decorator, CIVIL ENGINEERING, SURVEYING, etc. CIVIL ENGINEERING, SURVEYING, etc. Ijight Railways. LIGHT RAILWAYS FOR THE UNITED KINGDOM, INDIA. AND TliE COLONIES : A Practical Handbook setting fortla the Principles on which Light Railways should be Constructed, Worked and Financed; and detailing the cost of Construction, Equipment, Revenue, and Working Exp-nces of Local Railways already established in the above- mentioned Countries, and in Belgium, France, Switzerland, &c. By John Charles Mackay, f.G.S., A.M. Inst. CE. Illustrated with 40 Photographic Plates and other Liiagrams. Medium 8vo, 15s. cloth. [Just published. Exactly what has been long wanted, and sure to have a wide sale." — Rail-way News. fFater Supply and Water-Works, THE WATER SUPPLY OF TOWNS AND THE CON- STRUCTION OF WATER-V/ORKS : A Practical Treatise for the Use of Engineers and Studen-s of Engineering. By W. K. Burton, A.M.Inst. C E., Pr -fessor of San'tary Engineering in the Imperial University, Tokyo, Japan, and Consulting Engineer to the Tokyo Water-works. With an Appendix on Tlie Effects of Earthquakes on Waterworks, by John Milne, F.R.S., Pro- fessor of Mining in tne Imperial University of Japan. With numerous P'ates and Illustrations. Su^^er-royal 8vo, 25s. buckram. \_Jjist ptiblished. " The whole art of waterworks construction is dealt with in a clear and comprehensive fashion 'in this handsome volume. . . . Mr. Burton's practical treatise shows in all its sections the fruit -of independent study and individual experience. It is largely based upon his own practice in the branch of engineering- of which it treats, and with such a basis a treatise can scarcely fail to be sug- -gfestive and useful." — Saturday^ Review. ' Professor Burton's book is sure ot a warm welcome among engineers. It is written in clear .and vigorous language and forms an exhaustive treatise on a branch of engineering the claims of which it would be ditlicult to over-estimate."— Scotsman. " The subjects seem to us to be ably discussed, with a practical aim to m.eet the requirement? •of all its probable readers. The volume is well got up, and the illustrations are excellent." The Lancet. Water Supply of Cities and Towns, A COMPREHENSIVE TREATISE on the WATER-SUPPLy OF CITIES AND TOWNS. By William Humber, A-M.Inst.C.E., and M. Inst. M.E., Author of "Cast and Wrought Iron Bridge Construction," &c. &c. Illustrated with 50 Double Plates, i Single Plate, Coloured Frontispiece, and upwards ot 250 Woodcuts, and containing 400 pages o* Text. Imp. dto. £6 6s. elegantly and substantially halt-bound in morocco, "The most systematic and valuable work upon water supply nitnerto uroauceQ in Hngiisn or •In any other language. . . . Mr. Humber's work is characterised almost throughout by an exhaustiveness much more distinctive of French and German than of English technical treatises . — Engitieer. "■ We can congratulate Mr. Humber on having been able to give so large an amount 01 infor- mation on a subject so important as the water supply of cities and towns. The plates, fiity m Bumber, are mostly drawings of executed works, and alone would have commanded the attentlor. of every engineer whose practice may lie in this branch of the profession." — Builder. Water Supply, RURAL WATER SUPPLY : A Practical Handbook on the Supply of Water and Constructionof Waterworks for small Country Districts. By Allan Greenwell, A.M.I.C.E., and W. T. Curry, A.M.I. C.E., F.G.S. With Illustrations. Crown 8vo, 5s. cloth. [Just published. " We conscientiously recommend it as a very useful book for those concerned in obtain- ing water for small districts, giving a great deal or practical information in a small compass." — Builder. " The volume contains valuable information upon all matters connected with water supply. . -, . It is full of details on points which are continually before waterworks' engineers." — Nature. Hydraulic Tables, HYDRAULIC TABLES, CO-EFFICIENTS, ana FORMULA for finding the Discharge of Water from Orifices, Notches, Weirs, Pipes, and Rivers. By John Neville, Civil Engineer, M.R.I. A. Third Ed., carefully Revised, with considerable Additions. Numerous Illusts. Cr. 8vo, 14s. cloth. " Alike valuable to students and engineers in practice ; its study will prevent the annoyance of jivoldable failures, and assist them to select the readiest means of successfully carrying out any given work connected with hydraulic engineering." — Mining journal. " It is, of all English books on the subject. the one nearest to completeness,".— ..4 rcAtfeo'. 10 CROSBY LOCK WOOD &- SON'S CATALOGUE. Hydraulics, HYDRA ULIC MANUAL. Consisting of Working Tables and Explanatory Text. Intended as a Guide in Hydraulic Calculations and Field Operations. By Lewis D'A. Jackson, Author of "Aid to Survey Practice," *' Modern Metrology,'' &c, Fourth Edition, Enlarged. Large cr. 8vo, 165. cl. " The author has had a wide experience in hydraulic engineering and has been a careful ob- server of the facts which have come under his notice, and from the great mass of material at his command he has constructed a manual which may be accepted as a trustworthy guide to this branch of the engineer's profession. We can heartily recommend this volume to all who desire to be acquainted with the latest develooment of this important subject." — Engitieeritig. " The standard-work in this department of mechanics." — Sco:sfna7i. "The most useful feature of this work is its freedom from what Is superannuated, and Its thorough adoption of recent experiments ; the text is, in fact, in great part a short account of the great modem experiments." — Natun. Water Storage, Conveyance, and Utilisation, WATER ENGINEERING : A Practical Treatise on the Measure- ment, Storage, Conveyance, andUtilisation of Water for the Supply of Towns> for Mill Power, and for other Purposes. By Charles Slagg, A.M.Inst.C.E., Author of "Sanitary Work in the Smaller Towns, and in Villages," &c. Second Edition. With numerous Illustrations, Crown 8vo, ys. 6d. cloth. "As a small practical treatise on the water supply ot towns, and on some applications of water-power, the work is in many respects excellent." — Engineerhtg: " The author has collated the results deduced from the experiments of the most eminent authorities, and has presented them in a compact and practical form, accompanied by very cleaT and detailed explanations. . . . The application of water as a motive power is treated very carefully and exhaustively."— Binlde-^. "For anyone who desires to begin the study of h3-draulicswith a consideration of the practica) applications of the science there is no better guide." — Architect. Drainage, . ON THE DRAINAGE OF LANDS, TOWNS, AND BUILD- INGS. By G. D, Dempsey, C.E„ Author of "The Practical Railway En- gineer," &c. Revised, with large Additions on Recent Practice is Drainage Engineering, by D. Kinnear Clark, M.Inst.C.E. Author ox "Tramways: Their Construction and Working," "A Manual of Rules, Tables, and Data for Mechanical Engineers." &c. Third Edition. Sinal? crown 8vo, 4s. 6d. cloth. ' [Just published. " The new matter added to Mr. Dempsey's excellent work Is characterised bv the comprehen- sive grasp and accuracy o! detail for which the name of Mr. D. K. Clark is a suMcient voucher." — AthenizuTn. " As a work on recent practice In drainage engineering, the book Is to be commended to ali who are making that branch of engineering science their special study." — Iron. " A comprehensive manual on drainage engineering, and a useful introduction to the student." — Building News. River Engiyieering, RIVER BARS: The Causes of their Formation, and their Treat- ment by " htduced Tidal Scour ; " with a Description of the Successful Re- duction by this Method of the Bar at Dublin. By L J. Mann, Assist. Eng. to the Dublin Port and Docks Board, Royal 8vo, js. 6d. cloth. "We recommend all interested in harbour works — and, indeed, those concerned In the Inv- provements of rivers generally— to read Mr. Mann's interesting work on the treatment of rivet bars, ' ' — Engi7ieer. Tramways and their VTorking, TRAMWAYS : THEIR CONSTRUCTION AND WORKING. Embracing a Comprehensive History of the System ; ■with an exhaustive Analysis of the various Modes of Traction, including Horse-Powsr, StearD, Cable Traction, Electric Traction, &c.; a Description of the Varieties of Roll- ing Stock ; and ample Details of Cost and Working Expenses. New Edition, Thoroughly Revised, and Including the Progress recently made in Tramway Construction, &C.&C. By D. Kinnear Clark. M.Inst.C.E. With numerous Illustrations and Folding Plates. In One Volume, 8vo, 780 pages, price 28s., bound in buckram. [Just published. " All interested in tramways must refer to It, as all railway engineers have turned to the author S- work ' Railway ^lachineTy-.'"— Engineer. " An exhaustive and practical work on tramway's, in which the history of this kind of locuroo Hon, and a description and cost of the various modes of laying tramways, are to be founr". ' — Building News. " The best form of rails, the best mode of constractlon, and the best mechanical appliances are so fairly indicated in ths work under review, that any engineer about to construct a tramwj y will be enabled at once to obtain the practical icformation wliich will be of most service tohiiti ?' — Athenteuvt, CIVIL ENGINEERING, SURVEYING, etc. ii Student's Text-Book on Surveying, PRACTICAL SURVEYING : A Text-Book for Students pre- paring for Examination or for Survey-work in the Colonies. By George W. UsiLL, A.M.I.C.E., Author of "The Statistics of the Water Supply of Great Britain." With Four Lithographic Plates and upwards of 330 Illustra- tions. Fourth Edition, Revised, including Tables ot Natural Sines, Tan- gents, Secants, &c. Crown 8vo, 7s. 6d. cloth ; or, on Thin Paper, bound in limp leather, gilt edges, rounded corners, for pocket use, 12s. 6d. " The best forms of instruments are described as to their construction, uses and modes of employment, and there are innumerable hints on work: and equipment such as the author, in his experience as surveyor, draughtsman, and teacher, has found necessary, and which the student In his inexperience will find most serviceable.'' — Engineer. ",The latest treatise in the English language on surveying, and we have no hesitation In say- ing that the student will find it a better guide than any of its predecessors . . . ■ Deserves to be recognised as the first book which should be put in the hanas of a pupil of Civil Engineering, and everj' gentleman of education who sets out for the Colonies would find it well to have a copy." — Architect. Survey JPractice, AID TO SURVEY PRACTICE, for Reprence tn Sxirveying, Level- ling, and Setting-out ; and in Route Surveys of Travellers by Land and Sea, With Tables, Illustrations, and Records. By Lewis D'A. Jackson, A.MJ.C.E., Author of " Hydraulic Manual," "Modern Metrology," &c. Second Edition, Enlarged. Large crown 8vo, 12s, 6d. cloth. "A valuable vade-->necnm for the sur\'eyor. We can recommeno this book as containing an admirable supplement to the teaching of the accomplished surveyor."— AthtJiczutn. " As a text-book we sho'old advise all surveyors to piace it in their libraries, and study well the matured instructions afforded in its pa.ges."—CoUiery Giiardian. '■ The author brings to his work a fortunate union of theory and practical experience which, aided by a dear and lucid style of writing, renders the book 3 very useful o-ce."— Builder. Surveying, Land and 3Iarine, LAND AND MARINE SURVEY ING, inKeierencetoXheVrQ- paration of Plans for Roads and Railways ; Canals, Rivers, Towns' Water Supplies; Docks and Harbours. With Description and Use of Surveying Instruments. By W. D. Haskoll, C.E., Author of " Bridge and Viaduct Con- struction," &c. Second Edition, Revised, with Additions. Large cr.Svo, 9s. cl. " This book must prove of great value to the student. We have no hesitation in recommend- ing it, feeling assured that it will more than repay a careful study." — Mechanical World. "A most useful and well arranged book. We can strongly recommend it as a carefuUy-writtea and valuable text-bock. It enjoys a well-deserved repute among 'sax\e.yox%." —Builder. " This volume cannot fail to prove of the utmost practical utility. It may be safely recommended to all students who aspire to become clean and expert surveyors."— Afiwwj^- yournai, Vield-Book for Engineers, THE ENGINEER'S, MINING SURVEYOR'S, AND CON- TRACTOR'S FIELD-BOOK. Consisting of a Series ol Tables, with Rules, Explanations of Systems, and use ot Theodolite for Traverse Surveying and Plotting the Work with minute accuracy by means of Straight Edge and Set Square only ; Levelling with the Theodolite, Casting-out and Reducing Levels to Datum, and Plotting Sections in the ordinary manner; setting-out Curves with the Theodolite by Tangential Angles and Multiples, with Right and Left-hand Readings of the Instrument : Setting-out Curves without Theodolite., on the System of Tangential Angles by sets of Tangents and Off- sets ; and Earthwork Tables to 80 feet deep, calculated for every 6 inches in depth. By W. D. Haskoll, CE. Fourth Edition. Crown 8vo, 12s. cloth. "The book is very handy ; the separate tables of sines and tangents to every minute will make it useful for many other purposes, the genuine traverse tables existing aU the same." — Athenceu-fn, "Every person engaged in engineering field operations will estimate the importance of such a work and the amount of valuable time which will be saved by reference to a set of reliable tables prepared with the accuracy and fulness of those given in this volume." — Railway News, Levelling, A TREATISE ON THE PRINCIPLES AND PRACTICE OP LEVELLING. Showing its Application to purposes of Railway and Civil Engineering, in the Construction of Roads ; with Mr. Telford's Rulesfor the same. By Frederick W. Simms, F.G.S., M.Inst.C.E. Seventh Edition, with the addition of Law's Practical Examples for Setting-out Railway Curves, and Trautwine's Field Practice of Laying-out Circular Curves. With 7 Plates and numerous Woodcuts. 8vo, 8s. 6d. cloth. *** Trautwine on Curves may be had separate, 5s. " The text-book on levelling in most ol our engineering schools and colleges. . . . The publishers have rendered a substantial service to the profession, especially to the younger members, by bringing out the present edition of Mr. Simms's useful book " — Efigtneer. Ji CROSBY LOCK WOOD S- SON'S CATALOGUE. I r-tgononietrivat tSurveyt^ig, AN OUTLINE OF THE METHOD OF CONDUCTING A TRIGONOMETRICAL SURVEY, for the Formation of Geographical and Topographical Maps and Plans, Military Recontiatssance, Levelling, &c., with Useful Problems, Formulae, and Tables. By Lieut. -General Frome, R.E. Fourth Edition, Revised and partly Re- written by Major General Sir Charles Warren, G.C.M.G., R.E With ig Plates and 115 Woodcuts. Royal 8vo, i6s. cloth. " The simple fact that a tourth edition .^as been called for is the Dest testi mony to Its nccrits No words of prs.ise from us can strengthen the position so well and so steadily maintamed by this work. Sir Charles Warren has re^^sed the entire v. ork, and made such additions as were necessary -to brhig every portion of the contents ud to the present date.' —Sroad Arrov . Curves, Tables for Setting-ouU TABLES OF TANGENTIAL ANGLES AND MULTIPLES for Setting-out Curves from 5 to 200 Radius. By Alexander Beazeley, M.Inst.C.E. Fourth Edition Printed on d8 Cards, and sold in a cloth box, waistcoat-pocket size, 3s. 6d- " Each table is printed on a small cara, wmcn, oemg placed on tne tneodoilte, leaves tne hand free to manipulate the instrument — no small advantage as regards the rapidity of w.ork." — Engifieer. " Verj' handy ; a man may know that all his days work must fall on two of these cards, which he puts into his own card-case, and leaves the re.«;t behind." — Atherurum Earthwork. HANDY GENERAL EARTHWORK TABLES. Giving the Contents in Cubic Yards of Centre and Slopes of Cuttings and Embank- ments from 3 inches to 80 fset in Depth or Heignt, for use with either f 6 feet Chain or 100 feet Chain. By J. H. Watson Buck, M.Inst.C.E. On a Sheet mounted in cloth case, 3s. dd. [Just published, Earthivork, EARTHWORK TABLES. Showing the Contents in Cubic Yards of Embankments, Cuttings, &c., of Heights or Depths up to an average of So feet. By Joseph Broadbent, C.E.. and Fraxcis Campin, C.E. Crown 8vo, 5s. cloth. " The way in which accuracy is attained, by a simple division of each cross section into three . elements, two in which are constant and one variable, is ingenious." — Athenceum. Warthwork, Measure7H€nt of. A MANUAL ON EARTHWORK. By Alex. J. S. Grab am, C.E. With numerous Diagrams. Second Edition. i8mo, 2S. 6d. cloth. "A great amount of practical information, verj' admirably arranged, and available for rough ► estimates, as well, eis for the more exact calculations required in the engineer's and contractor's offices. ■ '—Artizan. Tunnelling, PRACTICAL TUNNELLING, Explaining m detail the Setting. out of the works, Shaft-sinking and Heading-driving, Ranging the Lines and Levelling underground, Sub-Excavating, Timbering, and the Construction of the Brickwork of Tunnels, with the amount of Labour required for, and the Cost of, the various portions of the work. By Frederick W.Simms, M.Inst. C.E. Fourth Edition, Revised and Further Extended, including the Most Recent (1895) Examples of Sub-aqueous and other Tunnels, by D. Kinnear Clark, M.Inst. C.E. Imperial 8vo, with 34 Folding Plates and other Illus- trations, £2 2S. cloth. ^^J list published. " The estimation in which Mr. Slmmss book on tunnelling has been held loi ovci iniriy years cannot be more truly expressed than in the words of the late Prof. Rankine : — ' The best source of in- formation or the subject of tunnels is Mr.F.W.Sim.ms'swork on Practical Tunnelling.'" — Archiiect, " It has been regarded from the first as a text-book of the subject. . . . Mr. C&rk has added - immensely to the value of the hook."— En^rtneer. Tunnel Shafts. THE CONSTRUCTION OF LARGE TUNNEL SHAFTS : A Practical and Theoretical Essay. By J. H. Watson Buck, M. Inst.C.E., Resident Engineer, London and Nortb-Western Railway Illustrated with Folding Plates. Royal &vo, 12s. cloth " Many of the methods given are of extreme practical value to tne mason ; and tne observations on the form of arch, the rules for ordering the stone, and the construction of the templates will be ' {ound of considerable use. We commend the book to the engineering profession." — Building Netvs " Will be regarded by civil engineers as of the utmost value, and calculated to save much tlire . and obviate many mistakes. " — Colliery Guardian. CIVIL ENGINEERING, SURVEYING, etc 13, Oblique Br id gen, A PRACTICAL AND THEORETICAL ESS A Y ON OBLIQUE BRIDGES. With 13 (arge Plaiea By the late George Watson Buck M.l.C.E. Fourth Edition, revised by his Son, J. H. Watson Buck, M.I.C.E. and with the addition of Description to Diagrams for Facilitating the Con-- struction of Oblique Bridges, by W. H. Barlow. M.I.C.E. Roy. 8vo, 12s. cL "The standara cexr-book tor an enj>^lneers regarding skew arches Is Mr. BucV's treatise, and it would be impossible to consult a better." — E}igineer. "Mr. Buck's treatise is recognised as a standard text-book, and his treatment has divested the subject of many of the intricacies supposed to belong to it. As a guide to the engineer eind archU tect, on a confessedly difficult subject, Mr. Bucks work is unsurpassed."— 5Mi/(^j«^iV«tj. Cast and Wruaght Iron Bridge Construction, A COMPLETE AND PRACTICAL TREATISE ON CAST AND WROUGHT IRCN BRIDGE CONSTRUCTION, including Iroty Foundations. In Three Parts — Theoretical, Practical, and Descriptive, By William Humber, A.M.Inst.C.E., and M.Inst. M.E. Third Edition, Re- vised and much improved, with 115 Double Plates (20 ol which now first appear in this edition), and numerous Additions to the Text. In Two Vols., imp. 4to, £6 i6s, 6d. half-bound in morocco. " A very valuable contribution to the standard literature oi clvU engineering. In addition to elevations, plans and sections, large scale details are given which very much enhance the instruc- tive worth of those illustrations." — Civil £n£z?ieer and A'rchiteci's jfottmal. Iron Bridges, IRON BRIDGES OF MODERATE SPAN : Their Construc- tion and Erection. By Hamilton Weldon Pendred, late Inspector of Ironwork to the Saliord Corporation. With 40 Illustrations. i2mo, 2s. cloth,. "Students and engineers should obtain this book for constant and practical VlS&."— Colliery Guardian. Oblique Arches. A PRACTICAL TREATISE ON THE CONSTRUCTION OP OBLIQUE ARCHES. By John Hart. Third Edition, with Plates. Im- perial 8vo, 8s. cloth. StiiticSf Graphic and Analytic, GRAPHIC AND ANALYTIC STATICS, in their Practical Appli- cation to the. Treatment of Stresses in Roofs, Solid Girders, Lattice, Bowstring and Suspension Bridges, Braced Iron Arches and Piers, and other Frameworks.- By R. Hudson Graham, C.E, Containing Diagrams and Plates to Scale. With numerous E.xamples, many taken from existing Structures. Specially arrangedfor Class-work in Colleges and Universities. Second Edition, Re- vised and Enlarged. 8vo, i6s. cloth " Mr. Graham's book will find a place wherever graphic and analytic statics are used or studied." —Eni:ineer. "The work is excellent from a practical point of view, and has evidently been prepared with- much care. The directions for working are ample, and are illustrated by an abundance of well- selected exzunples. It is an excellent text-book for the practical draughtsman." — Aihenau-m. eHeders, Strength of, GRAPHIC TABLE FOR FACILITATING THE COM PUT A^ TION OF THE WEIGHTS OF WROUGHT IRON AND STEEL GIRDERS, etc., for Parliamentary and other Estimates. By J. H. Watscn Buck, M.Inst.C.E. On a Sheet, zs. 6d. Strains, Calculation of, A HANDY BOOK FOR THE CALCULATION OF STRAINS IN GIRDERS ANDSIMILARSTRUCTURES.AND THEIRSTRENGTH. Consisting of Formulae and Corresponding Diagrams, with numerous details' for Practical Application, &c. By William Humber. A-M. Inst. C.E. , &c, Fifth Edition. Crown 8vo, nearly 100 Woodcuts and 3 Plates, 7s. fid. clotl , " The formula are neatly expressed, and the diagrams good."—A(keniSU7K, " We heartily commend this really handy book to our engineer and curchitect readers,'— £n4 -■ lish Mecha'nir. ia CROSBY LOCKWOOD &' SON'S CATALOGUE. Trusses, TRUSSES OF WOOD AND IRON. Practical Applications of Sciencein Determining the Stresses, Breaking Weights, Safe Loads, Scantlings, and Details of Construction, with Complete Working Drawings. By William Griffiths, Sarveyor, Assistant Master, Tranmere School of Science and Art. Oblong 8vo. 4s. 6d. cloth. " This handy little book enters so minutely Into everj' detail connected with the oonstruction of roof trusses, that no student need be ignorant of these matters," — Practical Engineer, Strains in Ironwork, THE STRAINS ON STRUCTURES OF IRONWORK; with Practical Remarks on Iron Construction. By F. W. Sheilds, M.Inst.C.E, Second Edition, with 5 Plates. Royal 8vo, 5s. cloth. " The student cannot find a better little book on this subject.' — Eng-imer. Barlow^ s Strength of MaterialSf enlarged hyJELumher, A TREATISE ON THE STRENGTH OF MATERIALS; with Rules for Application in Architecture, the Construction of Suspension Bridges, Railways, &c. By Peter Barlow, F.R.S. A New Edition, Revised by his Sons, P. W. Barlow, F.R.S. , and W. H. Barlow, F.R.S. ; to which are added, Experiments by Hodgkinson, Fairbairn, and Kirkaldy; and Formulse for Calculating Girders, &c. Arranged and Edited by Wm. Humber, A-M.Inst.C.E. Demy 8vo, 400 pp., with 19 large Plates and numerous Wood- cuts, iSs. cloth. '• Valuable alike to the student, tyro, and the experienced practitioner, It will always rank in ^ature, as it has hitherto done, as the standard treatise on that particular subject." — Eng^ineer, " There is no greater authority than Barlow." — Bicilding Nctjus. " As a scientific work of the first class, it deserves a foremost place on the bookshelves of every civil engineer and practical tcechanic."— £;i^/w/j Medux-aic. Cast Iron and other Metals, Strength of, A PRACTICAL ESSAY ON THE STRENGTH OF CAST IRON AND OTHER METALS. By Thomas Tredgold, C.E. Fifth Edition, sncluding Hodgkinson's Experimental Researches. 8vo, 12s. cloth. Maihvay Working. SAFE RAILWAY WORKING. A Treatise on Railway Acci- dents: Their Cat{se and Prevention; with a Description of Modern Appliances and Systems. By Clement E. Stretton, C.E. With Illustrations and Coloured Plates. Third Edition. Enlarged. Crown 8vo, 3s. 6d. " A book tor the engineer, the directors, the managers ; and, In short, all who wish for informa- tion on railway matters will find a perfect encyclopaedia in ' Safe Railway Working.' "—Rail-way " We commend the remarks on railway signalling to all railway managers, especially where a uniform code and practice is advocated.' —Herepath's Rail-way Journal. "The author maybe congratulated on having collected, in a very convenient form, much valuable information on the principal questions affecting the safe v.crking of railways."— .R«»Z- ivay Engineer. Heat, Expansion by. EXPANSION OF STRUCTURES BY HEAT. By John Keily, C.E., late of the Indian Public Works and Victorian Railway Deparl- mentSt Crown 8vo, 3s, 6d. cloth. Summary of Contents. Section I. Formulas and Data, Section VI, Mechanical Force op Section II. Metal Bars. Heat. Section III. Simple Frames. Section VII. Work of Expansioii Section IV. Complex Frames and and Contraction. Plates. Section VIII, Suspension Bridges. Section V. Thermal Conductivity. Section IX. Masonry Structures " The aim the author has set before him, viz., to show the effects of heat upon metallic and other structures, is a laudable one, for this is a branch of physics upon which the engineer or archi tect can find but little reliable and comprehensive data in books." — B:i«er. HUMBERTS PROGRESS OF MODERN ENGINEERING. Fourth Series. Imp, 4to, with 36 Double Plates, Photographic Portrait ot John Fowler, late Pres. Inst. C.E., and copious descriptive Letterpresf, Specifications, &c., £3 3s. half-morocco. List of the Plates and Diagrams. Abbey Mills Pumping Station, Main Drain. [ Mesopotamia ; Viaduct oyer the River Wya, ^e. Metropolis (4 plates) ; Barrow Docks {3 i Midland Railway (3 plates) ; St. Germans Vla- plates) ; Manquis Viaduct, Santiago and Val- ■• ^ „ -r^ •, , , duct, Cornwall Railway (2 plates) ; Wrought- Iron Cylinder for Diving Bell ; Millwall Docks (6 plates) ; Milroy's Patent Excavator ; Metr«>- politan District Railway (6 plates); Huboun, Ports, and Breakwaters (3 plates). paraiso Railway (2 plates) ; Adam's Locomo- tive, St. Helen's Canal Railway (2 plates) ; Cannon Street Station Roof, Charing Cross Railway (3 plates) ; Road Bridge over the River Moka (2 plates) ; Telegraphic Apparatus for 1 ' ' We gladly welcome another year's issue of this valuable publication ftom the able pea of Mr. Humber. The accuracy and general excellence of this work are well known, while its useful aess in giving the measurements and details of some of the latest examples of engineering, as carried out by the most eminent men io the profession, cannot be too highly prised."— ^rriya«. i6 CtiOSBY LOCKWOOD &- SON'S CATALOGUE. THE POPULAH WORKS OF MICHAEL HEYNOLuS (" The Engine Driver's Friend ") Locomotive- Engine Driving, LOCOMOTIVE-ENGINE DRIVING . a Practical MamiaL foy Engineersin charge of Locomotive Engines. By Michael Reynolds. Membe> ot the Society 01 Engineers, formerly Locomotive Inspector L. B.and S. C. R Ninth Edition. Including a Key to the Locomotive Engine. With Illus- trations and Portrait ot Author. Crown 8vo. 4s. 6d. clotQ. "Mr. Reynolds has supplied a want, and has supplied it well. We can conhdentiy reconuuend the book, not only to the practical driver, but to everyone who t.<- ed. stronglj bound in leather. [J-ust piiblished. Summary of Contents. Signs AND Symbols, Decimal Frag- for Boilers.— Lloyd's Weight of -TioNS. — Trigonometry. — Practical Geometry. — Mensuration. — Cen- tres and Moments of Figures. — Moments of Inertia and Radii of Gyration. — Algebraical Expres- sions for Simpson's Rules. — Me- chanical Principles. — Centre of Gravity.— Laws of Motion. — Dis- placement, Centre of Buoyancy. — Centre of Gravity of Ship's Hull. — Stability Curves and Metacen- tres. — Sea and Shallow-water Waves.— Rolling of Ships.— Pro- pulsion AND Resistance of Vessels. — Speed Trials. — Sailing, Centre of Effort.— Distances down Rivers, Coast Lines. — Steering and Rud- ders OF Vessels. — Launching Cal- culations AND Velocities.— Weight OF Material and Gear. — Gun Par- ticulars AND Weight. — Standard Gauges. — Riveted Joints and Rivet- ing. — Strength and Tests of Mate- rials. — Binding and Shearing Stresses, ETC. — Strength of Shaft- ing, Pillars, Wheels, etc. — Hy- draulic Data,etc. — Conic Sections, Catenarian Curves.— Mechanical Powers, Work. — Board of Trade Regulations for Boilers and En- gines. — Board of Trade Regula- Chains.— Lloyd's Scantlings for Ships. — Data of Engines and Ves- sels. -Ships' Fittings and Tests.— Seasoning Preserving Timber. — Measurement of Timber. — Alloys, Paints, Varnishes. — Data for Stowage. — Admiralty Transport Regulations. — Rules for Horse- power, Screw Propellers, etc. — Percentages for Butt Straps, etc. — Particulars of Yachts. — Masting AND Rigging Vessels.— Distances of Foreign Ports. — Tonnage Tables. — Vocabulary of French AND English Terms. — English Weights and Measures — Foreign Weights and Measures. — Decimal, Equivalents. — Foreign Money. — Discount and Wage Tables. — Use- ful Numbers and Ready Reckoners — Tables of Circular Measures. — Tables of Areas of and Circum- ferences of Circles. — Tables of Areas of Segments of Circles. — Tables of Squares and Cubes an-d Roots of Numbers. — Tables of Logarithms of Numbers. — Tables OF HyperbolicLogarithms. — Tables OF Natural Sines, Tangents, etc. — Tables of Logarithmic Sines, Tangents, etc. tions for Ships. — Lloyd's Rules I " In these days of advanced knowledge a work like this is of the greatest value. It contains a vast amount of information. We unhesitatingly say that it is the most valuable compilation for its Epecific purpose that has ever been printed. No naval architect, engineer, surveyor, or seamciii, wood or iron shipbuilder, can afford to be without this v/ork." — Naictical Magazine. "Should be'used by all who are engaged in the construction or designs of vessels. . . . WUl be found to contain the most useful tables and formulae required by shipbuilders, carefully collected from the best authorities, and put together in a popular and simple form." — Engineer. "The professional shipbuilder has now, m a convenient and accessible form, reliable data for solving many of the numerous problems that present themselves in the course of his work." — Iron. " There is no douDt that a pocket-book of this description must be a necessity in the ship- building trade. . . . The volume contains a mass J>iHg- IVorld. Bocket-BooJc for Marine Engineers, A POCKET-BOOK OF USEFUL TABLES AND FOR- MULjS for marine ENGINEERS. By Frank Proctor, A.I.N.A, Third Edition. Royal 32mo, leather, gilt edges, with strap, 4:, "We recommend it to our readers as going far to supply a long-felt •,va.nt."—A''azaiScienc*. "A most 'Aseful companion to all marine engineers." — United Service Gazettt. Introduction to Marine Engineering, ELEMENT A R Y ENGINEERING : A Manual for Young Marine Engineers and Apprentices. In the Form of Questions and Answers on Metals, Alloys, Strength of Materials, Construction and Management ot Marine Engines and Boilers, Geometry, &c. &c. With an Appendix of Useful Tables. By John Sherren Brewer, Government Marine* Surveyor, Hong- kong. Third Edition. Small crown Svo, is. 6d. cloth, " Contains much valuable information for the class for whom it is intended, especially in the chapters on the management of boilers and engines." — Nautical Mag^azine, "A useful introduction to the more elaborate t&yX-\>oo\:s."—Scots7nan. " To a student who has the requisite desire and resolve to attain a thorough knowledge, Mr. Brewer offers decidedly useful )xe\p."—Athenaum. Navigation, PRACTICAL NAVIGATION. Consisting of The Sailor's Sea-Book, by James Greenwood and W. H. Rosser • together with the requisite Mathematical and Nautical Tables for the Working of the Problems, by Henry Law, C.E., and Professor J. R. Young. Illustrated; i2mo, 7s. strongly half-bound. Sailinaking. THE ART AND SCIENCE OF SAILMAKING. By Samuel B, Sadler, Practical Sailmaker, late in the employment of Messrs. Ratsey and Lapthorne, of Cowes and Gosport. With Plates and other Illustrations. Small 4to, I2S. 6d. cloth. "This work is very ably written, and is illustrated by diagrams and carefully- worked calcula- tions. The work should be in the hands of every sailmaker, whether employer or employed, as it cannot fail to assist them in the pursuit of their important B.\oc3.X\oi\s."—Jsle of Wi^^kt Herald. " This extremely practical work gives a complete education in all the branches of the manu- facture cutting out, roping, seaming, and goring. It is copiously illustrated, and will form a first* rate text-book ar.d za\de."—Ports}noiith Ti^nes. " The author of this work has rendered a distinct ser^-ice to all interested in the art of sail- making. The subject of which he treats is a congenial one. Mr. Sadler is a practical sailmaker and has devoted years of careful obsen'ation and stud5- to the subject : and the results of the experience thus gained he has set forth in the volume before us." — Steamship. Chain Cables, CHAIN CABLES AND CHAINS. Comprising Sizes and Curves of Links, Studs, &c., Iron for Cables and Chains, Chain Cable and Chain Making, Forming and Welding Links, Strength of Cables and Chains, Certificates for Cables, Marking Cables, Prices of Chain Cables and Chains, Historical Notes, Acts of Parliament, Statutory Tests, Char.ices lor Testing, List of Manufacturers of Cables, &c. &c. By Thomas W.Traill, F.E.R.N., M.Inst. C.E., Engineer Surveyor in Chief, Board of Trade, Inspector of Chain Cable and Anchor Proving Establishments, and General Superin- tendent, Lloyd's Committee on Proving Establishments. With numerous Tables. Illustrations and Litho2raphic Drawings. Folio, {i 2S. cloth. " It contains a vast amount ot valuable InJormatlon. Nothing seems to be wancini; to make it complete and standard work of reference on the SMO\&ct."— Nautical Ma^aatu. MINING AND METALLURGY. ig MINING A ND METAL LURGY. Mining Machinery. MACHINERY FOR METALLIFEROUS MINES: A Practica! Treatise for Mining Engineers, Metallurgists, and Managers ot Mines. By E. Henry Davies, M.E., F.G.S. Crown 8vo, 580 pp., with upwards of 300 Illustrations, 12s. 6d. cloth. [Just published. " Mr. Davies, in tliis handsome volume, has done the advanced student and the managrer of mines good service. Ahnost every kind of machinery in actual use is carefully described, and tlKj woodcucs and plates are good." — Athen<£um. " From cover to cover the v/ork exhibits all the same characteristics which excite the confi- dence and attract the attention of the student as he peruses the hrst page. The work may safely be recommended. By its publication the literature connected with the industry will be enriched, and the reputation of its author enhanced." — Mining- Journal. " Mr. Davies has endeavoured to bring before his readers the best of everything in modexTt mining appliances. His work carries iuternal evidence of the author's impartialit}', and this C£«v stitutes ce of the great merits of the book. Throuijhout his work the criticisms are based on -Itis own or other reliable experience.' — Iron and Steel Trades' Journal. "The work deals witii nearly every class of machinery or apparatus likely to be met with or required in connection with metalliferous mining, and is one which we have every confidence in recommending." — Practical hngineer. Metalliferous Minerals and Mining, A TREATISE ON METALLIFEROUS MINERALS AND MINING. By D. C. Davies, F.G.S. , Mining Engineer, &c., Author of "A Treatise on Slate and Slate Quarrying." Fifth Edition, thoroughly Revised and much Enlarged, by his Son, E. Henry Davies, M.E., F.G.S. With about 150 Illustrations. Crown 8vo, 125. 6d. cloth. "Neither the practical miner nor the general reader interested In mines can have a better book for his companion and his guide." — Mining- Journal. IMining PVorld, . "We are doing our readers a service in calling their attention to this valuable work." " A book that will ,iot only be useful to the geologist, the practical miner, and the metallurgiet tjut aiso very interesting to the general public."— /rci;^. "As a history of the present state of mining throughout the world this book has a real valua and it supplies an actual want." — Aihe-naum. Earthy Minerals and Mining, A TREATISE ON EARTHY &^ OTHER MINERALS AND MINING. By D. C. Davies, F.G.S., Author of " Metalliferous Minerals," &c. Third Edition, revised and Enlarged, by his Son, E. Henry Davies M.E., F.G.S. With about 100 Illustration?. Crown 8vo, 12s. 6d. cloth. " We do not remember to have met with any English work on mining matters that contalas the same amount of information packed in equaUj' convenient form." — Academ-y. " We snould be incUned to rank it as among the very best of the handy technlceil and trades aianuals which have recently appeared."— £riiisk Quarterly Revie-w. Metalliferous Mining in the United Kingdom. BRITISH MINING : A Treatise on the History, Discovery, Practical Development, and Future Prospects of Metalliferous Mines in the United King^ dam. By Robert Hunt, F.R.S., Editor of " Ure's Dictionary of ArtSj Manufactures, and Mines," &c. Upwards of 950 pp., with 230 Illustrations. Second Edition, Revised. Super-royal 8vo, £2 zs, cloth. "One of the most vamaoie works of reierence oi modern times. Mr. Hunt, as Keeper of Mlnlqg Records of the United Kingdom, has had opportunities for such a task not enjoyed by anyone else and has evidently made the most ol them. . . . The language and style adopted are good, and the treatment of the various subjects laborious, conscientious, and scientific." — Engi->ieering. "The book is, in fact, a treasure-house of statistical information on mining subjects, and wa Know of no other work embodying so great a mass of matter of this kind. Were this the only merit of Mr. Hunt s volume, it would be sufficient to render it indispensable in the library of everyone interested in the development of the mining and metallurgical industries of this coun' ry.' — Alhenizu7n. "A mass of Information not elsewhere available, and of the greatest value to those who may De Interested in our great mineral industries." — Engifieer. Underground I*uinping Machinery, MINE DRAINAGE. Being a Complete and Practical Treatise on Direct-Acting Underground Steam Pumping Machinery, with a Descrip- tion of a large number of the best known Engines, their General Utility and the Special Sphere of their Action, the Mode of their Application, and their merits compared with other forms of Pumping Machinery. By Stephen MicHELL. Svo, 15s. cloth. "Will be highly esteemed by colliery owners and lessees, mining engineers, and students generally who require to be acquainted with the best means of securing the drainage of mines. It is a aaost valuable work, and stands almost alone in the literature of steam pumping machinerTS'." — Colliery Guardian, 'Much valuable Information !s given, so that the book is thoroughly worthy of an extensive circulation amongst practical men and purchasers of machinery." — Miniftg Journal- lo CROSBY LOCKWOOD ^ SON'S CATALOGUE Prospecting for Gold and other Metals, THE FROSPECTOR'S HANDBOOK: A Guide for- the Pro- - spector and Traveller in Search of Metai-Bearingor other Valuable Minerals By J. W. Anderson, M.A. (Camb.), F.R.G.S., Author of "Fiji and New Caledonia." Sixth Edition, thorougblv Revised and much Enlarged. Small crown 8vo, 3s. 6d. cloth ; or, 4s 6d. leather, pocket-book form, with tuck. typist published. "Will supply a much felt want, especially among Colonists, in whose way are so oiteu thrown many mmeralogical specimens the value of which it is difficult to determine."— /•^ij^ineer. "How to find commercial minerals, and how to identify them when they are found, are the leadlMT points to which attention is directed. The author has manag^ed to pack as much practical aftsil mto his pages as would supply material for a honk three times its size."—\finim '^ou-^tuti Mining Notes and Forniiilce. ^OTES AND FORMULAE FOR MINING STUDENTS. By ^HN Herman Merivale, M.A., Certificated Colliery Manager, Professor of Mining in the Durham College of Science, Newcastle-upon-Tyne. Third Edition, Revised and Enlarged. Small crown 8vo, 2S. 6d. cloth. " Invaluable to anyone v-jfao is working up for an examination on mining subjects."— /ro« ajid Coal Trades Review. "The author has done his work in an exceedingly creditable manner, and has produced a book rtat will be of service to students, and those who are practically engaged in mining operations."— Enginetr, Mandybooh for 3Iiners, THE MINER'S HANDBOOK : A Handy Book of Reference on (he Subjects of Mineral Deposits, Mining Operations. Ore Dressing, &c. For the Use of Students and others interested in Mining matters. Compiled by John Milne, F.R S., Pro'^essor of Mining in the Imperial University of Jap^n. Revised Edition. Fcap. Svo, 7s. 6rf. leather. [Just published. " Professor Milne's handbook is ^Jure to be received with favour by all connected with mining-, and will be extremely popular among students." — Athen(zzi7}i. Miners' and 3Ietallurgists' Pocket-Book. A POCKET-BOOK FOR MINERS AND METALLURGISTS. Comprising Rules, Formulae, Tables, and Notes, for Use in Field and Ofi&ce Work. By F. Danvers Power, F.G.S., M.E. Fcap. 8vo, gs. leather. " This excellent book is an admirable example of its kind, and ought to find a large sale amongst Entjlish-speaking prospectors and mining engineers." — Eiigi'/iecriiig. " A useful ■vade-meaitn containing a mass of rules, formulas, tables, and various other informa- tion, necessary for daily eference," —Iron. Mineral Surveyijtg and Valuing, THE MINERAL SURVEYOR AND VALUER'S COMPLETE GUIDE, comprising a Treatise on Improved Mining Surveying and the Valua Hon of Mining Properties, with New Traverse Tables. By Wm. Lintern. Third Edition, Enlarged. lamo, 4s, cloth. " A valuable zmd thoroughly trustworthy guide." — Iron and Coal Trades Review. Asbestos and its Uses, ASBESTOS : Its Properties, Occurrence, and Uses. With some Account of the Mines of Italy and Canada. By Robert H. Jones. With Eight Collotype Plates and other Illustrations. Crown 8vo, 12s. 6d. cloth. " An interesting and invaluable -wozk."— Colliery Guardian. Tron, Metallurgy of, METALLURGY OF IRON. Containing History of Iron Manu- facture, Methods of Assay, and Analyses of Iron Ores, Processes of Manu- facture of Iron and Steel. &c. By H. Bauerman, F.G.S., A.R.S.M With numerous Illustrations. Sixth Edition. Enlarged, tamo. ss. 6d. cloth. " Carefully written, it has the merit of brevity and cfticiseness, as to less important points ; while all material matters are very fully and thoroughly entered into."— J>la?tda>-' department. ... A mining engineer could scarcely go wrong who followed this work." — Colliery Gicardia>i. "This is the most complete 'aU round' work on coal-mining published in the English language. . . . No library of coal-mining books is complete without it." — Colliery Engineer (Scranton, Pa., U.S.A.). " Mr. Pamely's work is in all respects worthy of our admiration. No person in any responsible position connected with mines should be without a co-py. " — lVest>ni?istcr Revietu. f)oal (ind Iron, THE COAL AND IRON INDUSTRIE!:^ OF THE UNITED ■ KINGDOM. Comprising a Description of the Coal Fields, and of tha Principal Seams of Coal, with Returns of their Produce and its Distribu- tion, and Analyses of Special Varieties. Also an Account of the occurrencQ of Iron Ores in Veins or Seams ; Analyses of each Variety ; and a History of the Rise and Progress of Pig Iron Manufacture. By Richard Meade, Assistant Keeper of Mining Records. With Maps. 8vo, £1 8s. cloth. " The book is one which must find a place on the shelves of all Interested In coal and Iron production, and in the iron, steel, and other metallurgical industries."— £'?ii^z«€«r. " Of this book we may unreservedly say that it is the best of its class which we have ever met. ... A book of reference which no one engaged in the Iron or coal trades should omit from hU library " — Iro^i atid Coal Trades RezHev. Coal Mining, COAL AND COAL MINING: A Rudimentary Treatise on. By the late Sir Warington W. Smyth, M.A., F.R.S., Chief Inspector of the Mines of the Crown. Seventh Edition, Revised and Enlarged. With numerous Illustrations. lamo, 4s. cloth boards. ' As an outhne is given of ever;- kno-.vn coal-field m this amd other countries, as well as of tte principal methods of working, the book will doubtless Interest a very large numoer of reiiders "— Mining Journal. Subterraneous Surveying, SUBTERRANEOUS SURVEYING, Elementary and Practical Treatise on, with and without the Magnetic Needle. By Thomas Fenwicr Surveyor of Mines, and Thomas Baker, C.E. Illust. izmo, 3s. cloth boards^ Granite Quamjing, GRANITES AND OUR GRANITE INDUSTRIES. Rj? George F. Harris, F.G.S., Membre de la Societe Beige de Geologie, Lec- turer on Economic Geology at the Birkbeck Institution, &c. With lUustr-a- tions. Crown Svo, as. 6d. cloth. "A clearly and weU--nTitten manual on the granite Industry." -'Scotsman. ' An interesting v,'ork, which will be deservedly esteemed." — CoU-.ery Guardian. ' An exceedingly interesting and valuable monograph on a subject which has hitherto received unaccountably little attention in the shape of systematic literary tt^aXxcexA."— Scottish Leader. 22 CROSBY LOCK WOOD &• SON'S CATALOGUE. €rolftf Metallurgy of, THE METALLURGY OF GOLD : A Practical Treatise on the Metallurgical Treatment of Gold-bearing Ores. Including the Proresses of Concentration, Chlorination and Extraction by Cyanide, and the Assaying, Melting, and Kenning of Gold. By M. Eissler, Mining Engineer and Metal- lurgical Chemist, for^l^r ^ Assistant Assayer of the U.S. Mint, San Fran- cisco. Fourth Edition, Enlarged. With about 250 Iliustrations and numercis FoMing Plate? and Working Drawings. 8vo, i6s. cloth. [j'!st published. "This book thoroughly deserves its title of a ' Practical Treatise.' The ■H-hole process of gold naffilngi from the breaking of the quartz to the assay of the bullion is described in clear and orderly'narrative and ^vith much, bu^not too much, fulness of detail." — Saturday Jic-zm^\ " The work is a storehouse of information and valuable data, and we strongly recommend It to all professional men engaged in the gold-mining industry." — MiniTig- youmal. GoUV EjutrftctioHi THE CYANIDE PROCESS OF GOLD EXTRACTION : and its Practical Application on the Witwatersrand Gold Fields in South Africa, by M. Eissler, M.E., Mem. Inst. Mining and Metallurgy, Author of " The Metallurgy of Gold," &c. With Diagrams and Working Drawings. Large srown 8vo, 7s. 6d, cloth. IJust published. " This book is just i\hat was needed to acquaint mining men with the actual working of a pro- cess which is not only the most popular, but is, as a general rule, the most successful for the extrac- tion of gold from tailings." — Mitii-iig- Journal. " The work will prove invaluable to all interested in gold mining, whether metallurgists or as investors." — Cheviical Nci-us. Silver, Metallurgy of. THE METALLURGY OF SILVER : A Practical Treatise on the Amalgamation, Roasting, and Lixiviaticn cf Silver Ores. Including the Assaying, Melting and Refining, of Silver Bullion. By M. Eissler, Author of "The Metallurgy of Gold,''' &c. Third Edition. With I'io Illustraticns. Crown 8vo, los. 6d. cloth. [j'lst published. " A practical treatise, and a technical work which we are con\'lnced will supply a long-felt want amongst practical men, and at the.same time be of value to students and others indirectly connected ■^th the industries."— J/i;n'«^ yo'iit-nai. " rrom first to last the book is thoroughly sound and reliable." — Colliery Giiardia-n. "For chemists, practical mmers, assayers, and investors alike, we do not know of any wort- on the subject so hajidy and yet so comprehensive." — Giass^ow Herald. Lead, Metallurgy of. THE METALLURGY OF ARGENTIFEROUS LEAD: A Practical Treatise on the Smelting of Silver-Lead Ores and the Refining of Lead Bullion. Including Reports on various Smelting Establishments and Descriptions of Modern Smelting Furnaces and Plants, in Europe and America. By M. Eissler, M.E., Author of "The Metallurgy of Gold," &G. Crown 8vo, 400 pp., with 183 Illustrations, 12s. 6d. cloth. " The numerous metallurgical processes, \\hich are fuUj' and extensively treated of, embrace eH the stages experienced in the passage of the lead from the various natural states to its issue from the refinerj- as an article of commerce." — Practical Ejigiiieer. "The present volume fuUy maintains the reputation of the author. Those who wish to obtain a thorough insight into the present state of this industry cannot do Letter than read this volume, and all raining engineers cannot fail to find manj- useful hints and suggestions in it." — l-r-.dustTHes. " It is most carefully written and illustrated with capital drawings and diagrams. In fact, it is Ebe work of an expert for experts, by whom it will be prized as an indispensable text-book."— Bristol Mercury. Iron Mining. THE IRON^ORES OF GREAT BRITAIN AND IRELAND : Their Mode of Occiarrence, Age, and Origin, and the Methods of Searching for and Working them, with a Notice of some of the Iron Ores of Spain. By J. D. Kendall, F.G.S., Mining Engineer. Crown Bvo, i6s. cloth. " The author has a thorough practical knowledge of his subject, and has supplemented a care- ful study of the available literature by unpublished information derived from his own obsenations. The result is a verj- useful volume which cannot fail to be of value to all interested in the iron industry of the countrj-.'' — hidustries. "Mr. Kendall is a great authority on this subject and writes from personal obser\'otion.' — Colliery Guardian. " Mr. Kendall s book is thoroughly well done. In it there are the outlines of the history of ore mining in every' centre and there is everjthing that we vant tc know as to the character of the ores of each district, their com.mercial value and the cost of working them " — Iror. and Stetl Trades jfoumal. ELECTRICITY, ELECTRICAL ENGINEERING, etc. 23 ELECTRICITY, EL ECTRICAL ENG INEERING, ete. lyynanio ^lanageinent. THE MANAGEMENT OF DYNAMOS: A Handybook of Theory and Practice for the Use of Mechanics, Engineers, Students and cihers in Charge of Dynamos, By G, \V. Lummis Paterson. With nume- rous Illustrations. Crown 8vo, 3s. 6d. cloth. ijust published. " A)i example which deserves to be taken as a model b}- other authors. The subject is treated in a manner which any intelligent man who is fit to be entrusted with charge of an engine should be able to understand. It is a useful book to all who make, tend or employ electric machinery."— Architect. "A most satisfactor)' book from a practical point of view. "We strongly commend it to the attention of every electrical engineering student." — Daily Chronicle. iLlectrical JEngineering, THE ELECTRICAL ENGINEER'S POCKET-BOOK OP MODERN RULES, FORMULA, TABLES, AND DATA. By K. R. Kempe, M.Inst.E.E., A, M.Inst.C.E., Technical Officer, Postal Telegraphs, Author of "A Handbook of _ Electrical Testing," &c. Second Edition, thoroughly Revised, with Additions. Royal 32mo, oblong, 5s. leather. "There is very^ little in the shape of formulas or data which the electrician is likely to want !n a hurrj' which cannot be found in its pages." — Practical Eiigineer. " A very useful book of reference for daily use in practical electrical engineering and its various applications to the industries of the present day." — Ira^t. " It is the best book of its kind." — Electrical Engi}ieer. "Well arranged and compact. The ' Electrical Engineer's Pocket-Book' Is a good one."— Electrician. [Review. " Strongly recommended to those engaged In the various electrical industries." — Electrical Electric Lighting. ELECTRIC LIGHT FITTING: A Handbook for Working Electricai Engineers, embodying Practical Notes on Installation Ivlanage- ment. By John W. Urqukart, Electrician, Author of " Electric Light," &c. With numerous Illustrations. Second Edition, Revised, with Additional Chapters. Crown 8vo, 5s. cloth. " This volume deals with what may be termed the mechanics of electric lighting, and is addressed to men who are already engaged in the work or are training for it. The work traverses a great deal of ground, and may be read as a sequel to the same author's useful work on ' Electric Light." " — Electricia7i. " The book is well worth the perusal of the workmen for whom it Is written." — Electrical Review. " We have read this book with a good deal of pleaisure. We believe that the book will be of use to practical workmen, who will not be alarmed by finding mathematical formulae which they are unable to understand." — Electrical Plant. Electric lAght, ELECTRIC LIGHT : Its Production and Use. Embodying Plain Directions for the Treatment of Dynamo-Electric Machines, Batteries,, Accumulators, and Electric Lamps. By J. W. Urquhart, C.E., Author oi "Electric Light Fitting," "Electroplating," &c. Fifth Edition, carefully Revised, with Large Additions and 145 Illustrations. Crown 8vo, 7s. 6i. cloth. " The whole ground of electric lighting is more or less covered and explained in a very clear and concise manner." — Electrical Rez/icTv. " Contains a good deal of very interesting information, especially in the parts where the author gives dimensions and working costs." — Electrical Eng-ineer. " A miniature vade-viscunt of the salient faSts connected with the science of electric light- ing.' '—Electricia n . " You cannot have a better book than ' Electric Light,' by Urquhart."— Engineer. " The book is by far the best that we have j'et met with on the subject." — Athenaum. Construction of Dynamos. DYNAMO CONSTRUCTION : A Practical Handbook for the Use of Engineer Constructors and Electricians-in-Ckarge. Embracing Frame- work Building, Field Magnet and Armature Winding and Grouping, Com- pounding, &c. With Examples of leading English, American, and Conti- nental Dynamos and Motors. By J. W. Urquhart, Author of "Electric Light," " Electric Light Fitting," &c. Second Edition, Revised and En- larged. With 114 Illustrations. Crown 8vo, 7s. 6d. cloth. \_Jiist published. " Mr. Urquhart's book is the first one which deals with these matters in such a way that the engmeering student can understand them. The book is ver}' readable, and the author leads his readers up to difficult subjects by reasonably simple tests." — Engineering- Review. " The author deals with his subject in a st3-!e so popular as to make his volum.e a handbook of great practical value to engineer constructors and electricians in charge."— .Scoi-jj^a:??. "'Dynamo Construction' more than sustains the high character of the author's previous publications. It is sure to be widely read by the large and rapidly-increasing number of practical electricians."— G&:j^ew Herald. 24 CROSBY LOCK WOOD S' SON'S CATALOGUE, New Dictionary of Electricity. THE STANDARD ELECTRICAL DICTIONARY. A Popu- lar Dictionary of Words and Terms Used in the Practice of Electrical Engi- neering. Containing upwards of 3,000 Definitions. By T. O'Connor Sloane, A.M., Ph.D., Author of "The Arithmetic of Electricity." &c. Crown 8vo, 630 pp., 350 Illustrations, ys, 6d. cloth. IJust published. " The work has manj' attractive features in it, and is beyond doubt, a well put together and useful publication. The amount of ground covered may be gathered from the fact that in the index about 5,000 references will be found. The inclusion of such comparatively modem words as ' impedance,' 'reluctance,' &c., shows that the author has desired to be up to date, and indeed there are other indications of carefulness of compilation. The work is one which does the author great credit and it should prove of great value, especially to students." — Electrical Review. \&xy complete and contains a large amount of useful information." — Industries. "An encyciopjedia of electrical science in the compass of a dictionary. The inlormation given is sound and clear. The book is well printed, well illustrated, and well up to date, and may be confidentlj- rerom.mended." — Builder. " The volume is excellently printed and illustrated, and should form part of the librar}- of every one who is connected with electrical matters." — Hard-ware Trade Journal. Electric Lighting of Ships. ELECTRIC SHIP.LIGHTING : A Handbook on tne Practical Fitting and Running of Ship's Electrical Plant. For the Use of Shipowners and Builders, Marine Electricians, and Sea-going Engineers-in-Charge. By J. W, Urqukart, C.E. With 88 Illustrations. Crown 8vo, -s. 6-1. cloth. " The subject of ship electric lighting is one of vast importance in these days, and Mr. Urqu- hart is to be highly complimented for placing such a valuable work at the service of the practical marine electrician." — T/ie Steo-mship. " Distinctly a book v.'hich of its kind stands almost alone, and for which there should be a demand." — Electrical Review. Country Souse Electric Lighting. ELECTRIC LIGHT FOR COUNTRY HOUSES : A Practical Handbook on the Erection and Running of Small Installations, with par- ticulars of the Cost of Plant and Working. By J. H. Knight. Crown 8vo, IS. wrapper. ' {Just published. Electric Lighting, THE ELEMENTARY PRINCIPLES OF ELECTRIC LIGHT. ING. By Alan A. Campbell Swinton, Associate I.E.E. Third Edition, Enlarged and Revised. With 16 Illustrations. Crown 8vo, is. 6d. cloth. ' ' Anyone who desires a short and thoroughly clear exposition of the elementary principles of electric-lighting cannot do better than read this little work.'' — Bradford Observer. Dynamic Electricity, THE ELEMENTS OF DYNAMIC ELECTRICITY AND MAGNETISM. By Philip Atkinson, A.M., Ph.D., Author of "The Ele- ments of Electric Lighting," &c. Cr. 8vo, with 120 Illustrations, los. 6d. cL Electric Motors^ &c. THE ELECTRIC TRANSFORMATION OF POWER and its Application by the Electric Motor, including Electric Railway Construction. By P. Atkinson, A.M., Ph.D., Author of " The Elements of Electric Light- ing," &c. With 96 Illustrations. Crown 8vo, 7s. 6d. cloth. Dynaino Construction, HOW TO MAKE A DYNAMO : A Practical Treatise for Amateurs. Containing numerous Illustrations and Detailed Instructions for Construct- ing a Small Dynamo, to Produce the Electric Light. By Alfred Crofts. Fifth Edition, Revised and Enlarged. Crown 8vo, 2S. clotn. "The instructions given m this unpretentious little book are sufficiently clear and explicit to enable any amateur mechanic possessed of average skill and the usual tools to be found in an amateur's workshop, to build a practical dynamo machine." — Electrician Text Book of Electricity, THE STUDENTS TEXT-BOOK OF ELECTRICITY, by Henry M. Noad, F.R.S. 630 pages, with 470 Illustrations. Cheaper Edition, Crown 8vo, gj. cloth. [Just published. Electricity. A MANUAL OF ELECTRICITY : Including Gaivumsm, Mag. netism, Dia-Magnetism, Electro-Dynamics. By Henry M. Noad, Ph D., F.R.S. Fourth Edition (1859). 8vo, £1 4s. cloth. ARCHITECTURE, BUILDING, etc, 25 ARCHITECTURE. BUILDING, eto. Building Construction* PRACTICAL BUILDING CONSTRUCTION : A Handbook for Students Preparin? for Examinations, and a Booii of Reference for Persons Ergaged in Building. By John P. Allen, Surveyor, Lecturer on Building Construction at ihe Durham College of Science, Newcastle. Medium 8vn, 4=0 pages, with T,Gco Illustrations. 12s. 6rf. cloth. [Just published. " This volume is one of the most complete expositions of building construction we have seen. It contains all that is necessary to prepare students for the various examinations in building con- struction."— .5zi;z7(3'z«,^ News. " The author depends nearly as much on his diagrams as on his type. The pages suggest the hand of a man of experience in building operations — and the volume must be a blessing to many teachers as well as to students. ' — The Architect. " The work is sure to prove a formidable rival to great and small competitors alike, and bids fair to take a permanent place as a favourite students' text-book. The large number of illustra- tions deserve particular mention for the great merit they possess for purposes of reference, in ex- actly corresponding to convenient scales." — Joiir. Inst. Brit. Archts, Masonry. PRACTICAL MASONRY : A Guide to the Art of Stone Cut- ting. Comprising the Construction, Setting-Ont, and Working of Stairs, Circular Work, Arches, Niches, Domes, Pendentives, Vaults, Tracery Win- dows, &c. For the Use of Students, Masons and other Workmen. By William R. Purchase, Building Inspector to the Town of Hove Royal 8vo, 134 pages, including 50 Lithographic Plates (about 400 separate Dia- grams), 75. M. cloth. \_Jii-st published. " The illustrations are well thought out and clear. The volume places within reach of the pro- fessional mason many useful data for solving the problems which present themselves day by day.' — Glasgow Herald. The New Builder's Price Book, 1896. LOCKWOOD'S BUILDER'S PRICE BOOK FOR 1896. A Comprehensive Handbook of the Latest Prices and Data for Builders, Architects, Engineers, and Contractors. By Francis T. W. Miller. 800 closely-printed pages, crown 8vo, 4s. cloth. " This book is a very useful one, and should find a place m every English office connected with the building and engineering professions." — hidustries. " An excellent book of reference.'' — Architect. " In its new and revised form this Price Book Is what a work of this kind should be — compre- hensive, reliable, well arranged, legible, and well \>Q\xa.6.:— British Architect. New London Building Act, 1894. THE LONDON BUILDING ACT, 1894; with the By-Laws and Regulations of the London County Council, and Introduction, Notes, Cases and Index. By Alex. J. David, B.A., LL.M. of the Inner Temple, Barrister-at-Law. Crown Bvo, 3s. 6rf. cloth. [Jitst published. " To all architects and district surveyors and builders, Mr. David's manual will be welcome." — Building- News. "The volume will doubtless be eagerly consulted by the building fraternity."— Illzistrated Carpenter ajid Bv.ilder. CONCRETE: ITS NATURE AND USES. A Book for Architects, Builders, Contractors, and Clerks of Works. By George L. SuTCLiFFE, A. R.I. B. A. Crown 8vo, 7s. 6d. cloth. IJust published. " The author treats a difficult subject in a lucid manner. The manual fills a long-felt gap. It is careful and exhaustive ; equally useful as a student's guide and a architect's book of reference." — Jotirnal of Royal Institution of British Architects. " There is room for this new book, which will probably be for some time the standard work on the subject for a builder's purpose." — Glasgow Herald. " A thoroughly useful and comprehensive work." — British Architect, MecJianics for Architects, THE MECHANICS OF ARCHITECTURE : A Treatise on Applied Mechanics, especially Adapted to the Use of Architects. By E. W. Tarn, M.A., Author of "The Science of Building," &c. Second Edition, Enlarged lUust. with 125 Diagrams. Cr. 8vo, 7s. 6d. cloth. IJiist published^ "The book is a ver}' useful and helpful manual of architectural mechanics, and really contains- sufficient to enable a careful and painstaking student to grasp the principles bearing upon the ma- jority of building problems. . . . Mr. Tarn has added, by this volume, to the debt of gratitude^ whiAi is owing to him 'oy architectural students for the many valuable works which he has pro- duced for their use." — The Builder. " The mechanics in the volume are really mechanics, and are harmoniously wrought in with- the distinctive protessional manner proper to the subject. —The Schoolmaster. 26 CROSBY LOCK WOOD S- SOfJ'S CATALOGUE. Designinq Buildings, THE DESIGN OF BUILDINGS: Being Elementary Notes on the Planning, Sanitation and Ornamentive Formation of Structures, based on Modern Practice. Illustrated -vitb Nine Folding Plates. By W. Wood- ley, Assistant Master, Metropolitan Drawing Classes, &c. Svo. 5s. cloth. Sir Wm. Chambers's Treatise on Civil Architecture, THE DECORATIVE PART OF CIVIL ARCHITECTURE. By Sir William Chambers, F.R.S. With Portrait, Illustrations, Notes, and an Examination of Grecian Architecture, by Joseph Gwilt, F.S.A. Revised and Edited bv W. H, Leeds. 66 Plates, 4to, 2is. cloth. Villa A-rchitectur^e, A HANDY BOOK OF VILLA ARCHITECTURE: Being a Series of Designs for Villa Residences in various Styles. With Outline Specifications and Estimates. By C. Wickes, Architect, Author of "The Spires and Towers of England," &c. 6i Plates. 4to, £i us. 6d. half-morcrco. " The -whole of the deslg^ns bear evidence of their being the work of an artistic architect, and •they wiU prove very valuable and sr.ggrestive." — Building- Ne-ws. Teort-Book for Architects, THE ARCHITECT'S GUIDE: Being a Text-Book of Useful Information for Architects, Engineers, Surveyors, Contractors, Clerks of Works, &c. By F. Rogers. Third Edition. Crown Svo, 3s. 6d. cloth. " As a text-book of useful information for architects, engineers, surveyors, &c., it would be bard to find a handier or more complete little volarRe."—Siandard, Ijitxear JPersiyect'tue ARCHITECTURAL PERSPECTIVE : The whole Course and Operations of the Draughtsman in Drawing a Large House in Linear Per- spective. Illustrated by 43 Folding Plates. By F. O, Ferguson. Second Edition, Enlarged. Svo, 3s. 6f?. boards. [Just published, " It is the most mtelligible of the treatises on this ill-treated subject that I have met with." — E. INGRESS Bell, Esq., in the R.I.B.A. Journal. Architectural Draiving, PRACTICAL RULES ON DRA WING, for the Operative Builder and Young Student in A rchitecturc. By G. Pyke. 14 Plates, 4to, 7S. 6a'., bds. Titruvius' Architecture. THE ARCHITECTURE of MARCUS VITRUVIUS POLLIO. Translated by Joseph Gwilt, F.S.A. , F.R.A..S. New Edition, Revised by the Translator. With 23 Plates. Fcap. Svo, 5s. cloth. Designing, Measuring, and Valuiiig, THE STUDENTS GUIDE to the PRACTICE of MEASUR- ING AND VALUING ARTIFICERS' WORK. Containing Directions for taking Dimensions, Abstracting the same, and bringing the Quantities into Bill, with Tables of Constants for Valuation of Labour, and for the Calcula- tion of Areas and SoliditieSj Originally edited by Edward Doeson. A.rchitect. With Additions by E. Wyndham Tarn, M.A. Sixth Edition, With 8 Plates and 63 Woodcuts. Crown Svo, ys. 6d. cloth, "This edition will be found the most complete treatise on the principles of measuring and raluing artificers' work that has yet been published." — Biiildiiig Neivs. JPocket Estimator and Technical Guide, THE POCKET TECHNICAL GUIDE, MEASURER, AND ESTIMATOR FOR BUILDERS AND SURVEYORS. Containing Tech- nical Directions for Measuring Work in all the Building Trades, Complete Specifications for Houses, Roads, and Drains, and an easy Method of Estimat- ing the parts cf a Building collectively. By A.C.Beaton. Seventh Edit. Waistcoat-pocket size, is. 6d. leither, gilt edges. " No builder, architect, sur\-evor, or valuer should be without his ' Beaton.' "—Building' Ne-ws. Donaldson on Specifications, THE HANDBOOK OF SPECIFICATIONS; or, Practical Guide to the Architect, Engineer, Surveyor, and Builder, in drawing up Specifications and Contracts for Works and Constructions. Illustrated by Precedents of Buildings- actually executed by eKiinent Architects and En- gineers. By Professor T. L. Donaldson, P.R.LB.A., &c. New Edition. 8vo. with upwards of 1,000 page? of Text, and 33 Pistes. £1 lis. 6d. cloth. " Valuable as a record, and more ^'aluabIe still as a book of precedents. . . . Suffice It to say that Donaldson's ' Handbook of Specifications ' must be bought bv all architects." — Builder. ARCHITECTURE, BUILDING, etc. 27 Bartholomew and Mogers' Specifications, SPECIFICATIONS FOR PRACTICAL ARCHITECTURE. A Guide to the Architect, Engineer, Surveyor, and Builder, With an Essay en the Structure and Science of Modern Buildings. Upon the Basis of the Work by Alfred Bartholomew, thoroughly Revised, Corrected, and greatly added to by Frederick Rogers, Architect. Third Edition, Revised, with Additions. With numerous Illustrations. Medium 8vo, 15s. cloth. " The collection of specifications prepared by Mr. Rogers on the basis of Bartholomew's work is too well known to need any recommendation from us. It is one of the books with which every young architect Must be equipped." — Architect. House Building and Repairing, THE HOUSE-OWNER'S ESTIMATOR ; or, Vv^hat will it Cost to Build, Alter, or Repair? A Price Book for Unprofessional People, as v?eil as the Architectural Surveyor and Builder. By J. D. Simon. Edited by F. T. W. Miller. A. R.I. B.A. Fourth Edition. Crown 8vo, 3s. 6d. cloth. "In two years it will repay its cost a nundred ttmes over."— Field. Vonstructiou, THE SCIENCE OP BUILDING : An Elementary Treatise on the Principles of Construction. By E. Wyndham Tarn, M.A., Architect. Third Edition. Revised and Enlarged. With 59 Engravings, Fcap. 8vo, 4s. cl. " A very valuable book, which we strongly recommend to all students." — Builder. BuiMing ; Civil and Ecclesiastical, A BOOK ON BUILDING, Civil and Ecclesiastical, including Church Restoration ; with the Theory of Domes and the Great Pyramid, &c. By Sir Edmund Beckett, Bart., LL.D., F.R.A.S. Fcap. Svo, 5.?. cloth. " A iDook which Is always amusing and nearly alwaj'S instractive," — Times, Hou.^e Building, DWELLING HOUSES, THE ERECTION OF. Illustrated by a Perspective View, Plans, Elevations and Sections of a Pair of Semi- Detarhed. Villas, with the Specification, Quantities and Estimates. By S. H. Brooks, Architect. Seventh Edition, thoroughly Revised. lamo, 2S. Sd. cioth. \jiist published. Sanitary Houses^ etc, THE SANITARY ARRANGEMENT OF DWELLING- HOUSES: A Handbook for Householders and Owners of Houses. By A. J. Wallis-Tayler, A.M. Inst. C.E. With numerous Illustrations. Crown 8vo, 2s. 6d. cloth. \_J list published. " This book will be largely read ; it will be of considerable service to the public. It is well .arranged, easily read, and for the most part devoid of technical terms." — Lancet. Ventilation of Buildings, VENTILATION. A Text Book to the Practice of the Art oj Veutilating Buildings. By W. P. Buchan, R.P. lamo, 4s. cloth. " Contains a great amount of useful practical information, as thoroughly interesting as it is •technically reliable." — British Architect. The Art of Plumbing, PLUMBING. A Text Book to the Practice of the Art or Craft of the Plumber, By Vvilliam Paton Buchan, R.P. Sisth Edition. 4s. cloth. "A text-book which may be safely put in the hands of every young plumber." — Builder. Geometry for the Architect ^ Engineer, etc, PRACTICAL GEOMETRY, for the Architect.. Engineer, and Mechanic. Giving Rules for the Delineation and Application of various Geometrical Lines, Figures and Curves, By E. V/. Tarn, M.A., Architect. 8vo, gs. cloth. " No book with the same objects in view has ever been published !n which the clearness of the rules laid down and the illustrative diagrams have been so satisfactory."— 5c<7^wja«. The Science of Geometry, THE GEOMETRY OF COMPASSES; or, Problems Resolved by thi mere Description of Circles, and tke use of Coloured Diagrams and Symbols. By Oliver Byrnf. Coloured Plates. Crown 8vo, 3s. 6d. cloth. 28 CROSBY LOCKWOOD *• SON'S CATALOGUE. CARP ENTRY, TIM BER, eto. JTredgoUVs Carpentry, Revised & Enlarged by Tarn, THE ELEMENTARY PRINCIPLES OF CARPENTRY. A Treatise on the Pressure and Equilibrium of Timber Framing, the Resist- ance of Timber, and the Construction of Floors, Arches, Bridges, Roo»s, Uniting Iron and Stone with Timber, &c. To which is added an Essay on the Nature and Properties oi Timber, &c., with Descriptioos of the kinds of Wood used in Building; also numerous Tables of the Scantlings of Tim» bar for different purposes, the Specific Gravities of Materials, &c. By Thomas Tredgold, C.E. With an Appendix of Specimens of Various Roofs of Iron and Stone, lUustiated. Seventh Edition, thoroughly revised and considerably enlarged by E. Wyndham Tarn, M.A., Author of "The Science of Build- ing," &c. With 6i Plates, Portrait of the Author, and several Woodcuts. Id One large Vol., 4to, priv.e £i 5s. cloth. " Ought to be in every architect's and every builder s llonry."— Builder. " A work whose monumental excellence must commend it wherever skilful carpentry Is coa- ceraed. The author's principles are rather confirmed than impaired by tima- The addidona) plates are of great intrinsic vai.-ae."—BuildinjS' News- Carpentry. CARPENTRY AND JOINERY. The Elementary Principles of Carpentry. Chiefly compo?ed from the Standard Work of Thomas Tredgold, C.E. With Additions, and a Treatise ox Joinery by E. W. Tarn, M.A. Fifth Edition, Revised and Extended. limo, 33.6^. cloth. =■>* Atlas of Thirty-five Plates to accompany and ILustrate the foregoing book. With Descriptive Letterpress. 4to. 6?. c'oth. " These two volumes form a complete treasur5' of carpentrj- and joinerj', and should be in the- hands of everj- carpenter and joiner in the empire." — Iron.. Woodtvorking Machinery. WOODWORKING MACHINERY : Its Rise, Progress, and Construction. With Hints on the Management of Saw Mills and the Economi- cal Conversion of Timber. Illustrated with Examples of Recent Designs by leading English, f rench, and American Engineers. By M Powis Rale, A.M.Inst.C.E., M.I.M.E. Second Edition, Revised, with large Additions. Large crown 8vo, 44.0 pp., gs. cloth. [Just published, " Mr. Bale is evidently an expert on the subject and he has collected so mucn inionnation that the book is all-sufficient for builders and others engaged in the conversion of timber."— Architect. "The most comprehensive compendium of wood-v.-orking machinery we have seen. The author is a thorough master of his suhiect."—Eui/din£' NeTos. Saw Mills, SA W MILLS : Their Arrangement and Management, and tha Economical Convei sion of Timber. (A Comj anion Volume to " Woodwork- ing Machinery,") By M, Powis Bale. Crown 8vo, ios. 6ti. cloth. " The adrntnistration of a large sawing establishment li discussed and the subiect examined from a financial standpoint. Hence the size, shape, order, and disposition of saw-mills and tha like are gone mto in detail, and the co'^rse of the timber is traced from its reception to its delivery In its converted state. We could not desire a more complete or practical Xx&a.'asA^'— Builder. Nicholson's Carpentry, THE CARPENTER'S NEW GUIDE ; or, Book of Lmes for Car- penters ; comprising all the Elementary Principles essential for acquiring a knowledge of Carpentry. Founded on the late Peter Nicholson's Standard Work. New Edition, Revised by A. Ashpitel, F.S.A. With Practical Rules on Drawing, by G. Pynb. With 74 Plates. 4to, £1 is. cloth. Circular Tf^orlc CIRCULAR WORK IN CARPENTRY AND JOINERY: A Practical Treatise on Circular Work of Single and Double Curvature. B7 George Collings. \v'ith Diagrams. Second Edit. i2mo, as. 6d. cloth limp. " An excellent example of what a book of this kind should be. Cheap In price, clear in defini- rion and practical in the examples selected. "—£«t/(fer. Handr ailing . HANDRAILING COMPLETE IN EIGHT LESSONS. On the Square-Cut System. By J. S. Goldthorp. Teacher of Geom.etry and Building Construction at the Halifax Mechanic's Institute. With Eight Plates and over 150 Practical Exercises. 4to, 3s. (d. cloth. " Likely to be of considerable value to joiners and others who take a pride in good work, we heartily ccmmend it to teachers and students." — Tiviber Trades youry.al. CARPENTRY. TIMBER, etc. 29. BCandrailing and Stairbuildiiig, A PRACTICAL TREATISE ON HANDRAILING : Showing New and Simple Methods tor Finding the Pitch of the Plank, Drawing the Moulds, Bevelling, Jointing-up, and Squaring the Wreath. By George CoLLiNGS. Second Edition, Revised and Enlarged, to which is added A Treatise on Stairbuilding tamo, 2s, 6d. cloth limp "Will be found ot practical utility in the execution of this difficult branch ot joinery."— Builaer. " Almobt every difficult phase of this somewhat intricate branch of joinery is elucidated by the aid of plates and explanatory letterpress." — Fufniiure Gazette. Timber Mercliaitt'a Companion, THE TIMBER MERCHANTS AND BUILDER'S COM- PANION. Containing New and Copious Tables of the Reduced Weight and Measurement of Deals and Battens, oi all sizes, from One to a Thousand Pieces, and the relative Price that each size bears per Lineal Foot to any fiven Price per Petersburg Standard Hundred ; the Price per Cube Foot of Square Timbei to any given Price per Load of 50 Feet; the proportionate Value of Deals and Battens by the Standard, to Square Timber by the Load ot 50 Feet; the readiest mode of ascertaining the Price of Scantling per Lineal Foot of any size, to any given Figure per Cube Foot, &c. &c. By William Dowsing Fourth Edition, Revised and Corrected. Cr. 8vo, 3s. cl, " Everj'thing is as concise and clear as it can possibly be made. There can be no doubt that every timber merchant and builder ought to possess x^.."— Hull Advertiser. " We are glad to see a fourth edition of these admirable tables, which for correctness and simplicity of arrangement leave nothing to be desired." — Timber Trades Journal, Practical Ti^nher Merchant, THE PRACTICAL TIMBER MERCHANT. Being a Guide for the use of Building Contractors, Surveyors, Builders, &c., comprising useful Tables for all purposes connected with the Timber Trade, Marks of Wood, Essay on the Strength of Timber, Remarks on the Growth of Timber, &c. By W. Richardson. Second Edition. Fcap. 8vo, 3s. 6d. cloth. "This handy manual contains much valuable information for tlie use ol timber merchants, oallders, foresters, and all others connected with the growth, sale, and manufacture of timber."— yournal of Forestry. Backing-Case Makers, Tables for, PACKING-CASE TABLES ; showing the number of Super- ficial Feet in Boxes or Packing-Cases, from six inches square and upwards. By W. Richardson, Timber Broker. Third Edition. Oblong 4to, 3s. 6d. cl, " Invaluable labour-saving tables." — Ironmonsrer. "W^ill save much labour and calculation." — Grocer. fiuperjicial Measurement THE TRADESMAN'S GUIDE TO SUPERFICIAL MEA- SUREMENT. Tables calculated from i to 200 inches in length, by i to 108 inches in breadth. For the use of Architects, Surveyors, Engineers, Timber Merchants, Builaera, &c» By James Hawkings. Fourth Edition. Fcap., 3s. 6d. cloth. " A useful collection of tables to facilitate rapid calculation of surfaces. The exact area of any jurface of which the limits have been ascertained can be instantly determined. The book will be found of the greatest utility to all engaged in building operations." — Scotsman. " These tables will be found of great assistance to all who require to make calculations In supef ficial measurement." — English Mechanic. Forestry, THE ELEMENTS OF FORESTRY. Designed to afford In- formation concerning the Planting and Care of Forest Trees for Ornament or Profit, with Suggestions upon the Creation and Care of Woodlands. By F.B. Hough. Large crown 8vo, los. cloth. Timber Importer's Guide, . THE TIMBER IMPORTER 'S, TIMBER MERCHANT'S, AND BUILDER'S STANDARD GUIDE. By Richard E. Grandy. Compris- ing an Analysis of Deal Standards, Home and Foreign, with Comparative Values and Tabular Arrangements for fixing Net Landed Cost on Baltic and North American Deals, including all intermediate Expenses, Freight Insurance, &c. &c. Together with copious Information ior the P>.etailer and Builder. Third Edition, Revised. i2mo, 2S. cloth limp. " Everything it pretends to be : built up gradually, it leads one from a forest to a treenail and throws in, as a makeweijfht. a host of material concerning bricks, columns, cisterns, &c. '—English Mechanic. 30 CROSBY LOCK WOOD S- SON'S CATALOGfJE. DECORATIVE ARTS, etc. Woods and Marbles (Ifnitation of), SCHOOL OF PAINTING FOR THE IMITATION OF WOODS AND MARBLES, as Taught and Practised by A. R. Van der Burg and P.. Van der Burg, Directors of the Rotterdam Painting Institution. Royal folio, i8^ by i2i in., Illustrated with 24 full-size Coloured Plates; also 12 plain Plates, comprising 154 Figures. Second and Cheaper Edition. Price ^i iis, 6J. List 0/ Plates. I, Various Tools required for Wood Painting 1 Finished Specimen— ig. Mahogany : specimen* — 8,3. Walnut: Preliminary Stages of Graining [ of various Grains and Methods of Manipulation- ■.-:_:,.. J c- : . T — 1, ..„_j r._ , — 20, 21. Mahogany: Earlier Stages and Finished Specimen — 22,23,24. Sienna Marble: Varieties- of Grain, Preliminary Stages and Finished Specimen — 25, 26, 27. juniper Wood : Methods of producing Grain, &c. : Preliminarj- Stages- and Finished Specimen — 2S, 29, 30. Vert de Mer Marble : Varieties of Grain and Methods- of Vr'orking Unfinished and Finished Speci. mens— 31. 32. 3?. Oak: Varieiies of Grain, Tools Employed, and Methods of Manipulation, Pre- liminary Stages and Finished Specimen — 34, 35, 36. Waulsort Marble: Varieties of Grain, Uo- finished and Finished Specimens. and Finished Specimen — 4. Tools used for Marble Painting and Methou of Manipulation — 6. St. Remi Marble: Earlier Operations and Finished Specimen — 7. Methods of Sketching differeni: Grains, Knots, i'c.— S. 9. Ash: Pre- h.ninary Stages and Finished Specimen — 10. Methods of Sketching Marble Grains— 11, la. Breche Marble : Preliminary Stages of Working smd Finished Specimen— 13. Maple: Methods of Producing the different Grains — 14, 15. Bird's- eye Maple: Preliminary Stages and Finished Specimen— 16. Methods of Sketching the dif- ferent Species of White Marble— 17, 18. Whit-e Marble; Preliminary Stages of Process and | "Those who desire to attain skill in the art of painting woods and marbles will find advantage- in consulting this book. . . . Some of the Working Men's Clubs should give their young men- the opportunity to study it."— Builder. " A comprehensive guide to the art. The explanations of the processes, the manipulation and management of the colours, and the beautifiiUy executed plates will not be the ieast valuable to the student who aims at making his work a faithful transcript of n&lure."— Building- Nezus, House JDecoration, ELEMENTARY DECORATION. A Guide to the Simpler Forms of Everyday Art. Together with PRACTICAL HOUSE DECORA- TION. By James W. Facey, V/ith numerous Illustrations. In One Vol., 5$. strongly half- bound House Fainting, Graining, etc, HOUSE PAINTING, GRAINING, MARBLING, AND SIGN PFif/r/iVG, A Practical Manual of. By Ellis A.Davidson. Six:h Editior. With Coloured Plates and Wood Engravings, ismo, 6s. clcvh boards. " A mass of information, of use to the amateur and of value to the practical maji."—£n£-iis/f Mechanic. Decorators, Receipts for, THE DECORATOR'S ASSISTANT : A Modern Guide to De- corative Artists and Amateurs, Painters, Writers, Gilders, &c. Containing upwards of 600 Receipts, Rules and Instructions ; with a variety of Informa- tion for General Work connected with every Class of Interior and Exterior Decorations, &c. Sixth Edition. 152 pp., crown 8vo, is. in wrapper "Full of receipts of value to decorators, painters, gilders, &c. The book contains the gist of larger treatises on colour and technical processes. It would be difficult to meet with a work so full- of varied information on the painter's art."— i>'wi/. Geology and Genesis, THE TWIN RECORDS OF CREATION ; or. Geology ana Genesis: their Perfect Harmony and Wonderful Concord. By George W. Victor le Vaux. Fcap. 8vo, 5s. cloth. " A valuable contribution to the evidences ol Revelation, and disposes very conclusively of the arguments of those who would set God's Works against God s Word. No real diflSculty is shirked, and no sophistry is left unexposed. —The Rock. Geology, RUDIMENTARY TREATISE ON GEOLOGY, PHYSICAL AND HISTORICAL. With especial reference to the British series of Rocks. By R. Tate, F.G.S. With 250 Illustrations. i2mo, 5s. cloth boards. NATURAL SCIENCE, etc. 33 DR. LARDNER'S COURSE OF NATURAL PHILOSOPHY. HANDBOOK OF MECHANICS. Re-wriiten and Enlarged by B. LoEWY, F.R.A.S. Post 8vo, 6s. cloth. "Mr. Loewy has carefully revised the book, and brought It up to modem requirements."— » Nature. HANDBOOK OF HYDROSTATICS &- PNEUMATICS. Enlarged • by B. Loewy, F.R.A.S. Post 8vo, 53, cloth. "For those 'who desire to attain an accurate knowledge of physicaJ science without the pro- found methods of mathematical investigation.' this work is well adapted." — Chejnical News. HANDBOOK OF HEAT. Edited and almost entirely Re-writtec by Benjamin Loewy, F.R.A.S., &c. Post 8vo, 6s. cloth. "The style is always clear and precise, and conveys Instruction without leaving any cloudlress^ or lurking doubts hc)rdnd."—En£-ineerin£^. HANDBOOK OF OPTICS. By Dr. Lardner. Edited by T. O. Harding, B.A. Post 8vo, 5s. cloth. "Written by an able scientific writer and beautifully illustrated.'" — Mecha7ii teehnical class or for the private student."— PaJ>er and Priming- Trades Joiiryial. Lteather Manufacture, THE ART OF LEATHER MANUFACTURE. Being a Practical Handbook, in which the Operations of Tanning, Currying, and Leather Dressing are fully Described, and the Principles of Tanning Ex- plained, and many Recent Processes Introduced ; as also the Methods for the Estimation of Tannin, and a Description of the Arts of Glue Boiling, Gut Dressing, &c. By Alexander Watt. Crown Svo, gs. cloth. "A sound, comprehensive treatise on tanning and Its accessories. It Is an eminently valuat>le production, which redounds to the credit of both author and publishers."— CAewiica/ Bez-iew. INDUSTRIAL AND USEFUL ARTS. 37 Watch Adjust iuff, THE WATCH ADJUSTER'S MANUAL: A Practical Guide for the Watch and Chronometer Adjuster in Making, Springing, Timing and Adjusting for Isochronism, Positions and Temperatures. By C. E. Fritts. 370 pages, with Illustrations, 8vo, i6s. cloth. [jiist publisher.. Horology, A TREATISE ON MODERN HOROLOGY, in Theory and Prac tice. Translated from the French of Claudius Saunier, ex-Director ot the School of Horology at Ma9on, by Julien Tripplin, F.R.A.S., Besanjon Watch Manufacturer, and Edward Rigg, M.A., Assayer in the Royal Mint. With 78 Woodcuts and 22 Coloured Copper Plates, Second Edition. Super- royal Svo, £2 2S. cloth ; £2 los. half-calf. " There Is no horological work in the English language at all to be compared to this produf - tloa of M. Saunier's for clearness and completeness. It is alike good as a guide for the student ard «s a reference for the experienced horologist and skilled workman.'' — Horological Joiit~nal. " The latest, the most complete, and the most reliable of those literary productions to -which continental watchmakers are indebted for the mechanical superioritjr over their English brethren —In fact, the Book of Books, is M. Saunier's 'Treatise.'"— PFatchmaier, jeweller and Silversmith. Watchjnaking. THE IVATCHMAKER'S HANDBOOK. Intended as a V/ork- shop Companion for those engaged in Watchmaking and the Allied Mechani- cal Arts. Translated from the French of Claudius Saunier, and considera- ably enlarged by Julien Tripplin, F.R.A.S., Vice-President of the Horological Institute, and Edward Rigg, M.A., Assayer in the Royal Mint. With numerous Woodcuts and 14 Copper P!ates= Third Edition. Crown 8vo, gs. cloth. " Each part is truly a treatise In Itself. The arrangement is good and the language is clear and concise. It is an admirable guide for the young watchmaker." — Engi^ieering, " It is impossible to speak too highly of its excellence. It fulfils every requirement in a hand. book Intended for the use ot a workman. Should be found in everj^ v.-orkshop."— J^'aiJcA and Clockmaker. " This book contains an immense number of practical details bearing on the daily occupatlcn cf a watchmaker." — Watck77iaker and Metalworker (Chicago), Watches and Timekeepers, A HISTORY OF WATCHES AND OTHER TIMEKEEPERS. By James F. Kendal, M. B.H.Inst, is. 6d. boards ; or 2s. 6rf. cloth gilt. "Mr. Kendal's book, for its size, is the best which hasyet appeared on this subject in the English language." — hidustries. " Open the book where you may, there is interesting matter in it concerning the ingenious devices of the ancient or modern horologer. The subject is treated in a liberal and entertaining spirit, as might be expected of a historian who is a master of the cxaSV—Saitcrday Review. Electrolysis of Gold^ Silver, Copper, etc, ELECTRO-DEPOSITION : A Practical Treatise on the Electrolysis 0/ Gold, Silver, Copper, Nickel, and other Metals and Alloys. With descrip- tions oi Voltaic Batteries, Magneto and Dynamo-Electric Machines, Ther- mopiles, and of the Materials and Processes used in every Department of the Art, and several Chapters on Electro-Metallurgy. By Alexander Watt, Author of " Electro-Metallurgy," &c. Third Edition^Revised. Crown Svo, gs. cloth. "Eminently a book for the practical worker in electro-deposition. It contains practical descriptions of methods, processes and materials as actually pursued and used In the workshop." — Engineer. Electro-Metallurgy, ELECTRO-META LL URG Y ; Practically Treated. By Alexandeh Watt, Author of " Electro-Deposition," &c Tenth Edition, including the most recent Processes. lamo, 4s. cloth boards. "From this book both amateur and artisan may leam everything necessary for the successful prosecution of electroplating."— /*•(?«. Working in Gold. THE JEWELLER'S ASSISTANT IN THE ART OF WORK- ING IN GOLD : A Practical Treatise for Masters and Workmen. Compiled from the Experience of Thirty Years'. Workshop Practice. By George E. Gee, Author of "The Goldsmith's Handbook," &c. Cr. Svo, 7s. 6d, cloth. " This manual of technical education is apparently destined to be a valuable auxiliary to a handicraft which is certainly capable of great improvement."— The 1 imes. " Very useful in the workshop, as the knowledge is practical, having been acquired by loug experience, and all the recipes and directions are guaranteed to be successful." — Jeweller anil Metal-worker, 38 CROSBY LOCK WOOD &• SON'S CATALOGUE. Electroplating, ELECTROPLATING : A Practical Handbook on the Deposi- tlon of Copper, Silvtr, Nickel, Gold, Aluminium, Brass, Platinum, &c. &c. With Descriptions cf the Chemicals, Materials, Batteries, and Dynamo Machines used in the Art. By J.W.Urquhart.C.E. Third Edition. Cr.8vo.5s, " An excellent work, giving the newest information."— ^(jro.'o^iVa/ Journal. Electrotyping, ELECTROTYPING . The Reproduction and Multiplication of Print. ing Surfaces and Works of Art by the Electro-deposition of Metals. By J. W, Urquhart, C.E. Crown 8vo, 5s. cloth. " The book Is thoroughly practical. The reader Is, therefore, conducted through the leading laws of electricity, then through the metals used by electrotypers, the apparatus, and the depositing processes, up to the Snsd preparation of the work." — Art yournai. Goldsmiths^ Worh, THE GOLDSMITH'S HANDBOOK. By George E. Gee, Jeweller, &c. Third Edition, considerably Enlarged. i2mo, 3s. 6d. cl. bds, "A good, sound educator, which will be accepted as an d.uthonty."—Horolo^ical Journal. Silversmiths' Work, THE SILVERSMITH'S HANDBOOK. By George E. Gee, Jeweller, &c. Second Edition, Revised. i2mo, 33. 6d. cloth. " The chief merit of the work is its practical character. . . The workers In the trade -n-iU speedily discover its merits when they sit down to study it."— En^iish Mechanic. *** The above two works together t strongly half'bound, price ys. Sheet Metal Working ^ SHEET METAL WORKER'S INSTRUCTOR : Comprising a Selection of Geometrical Problems and Practical Rules for Describing the Various Patterns Required by Zinc, Sheet-Iron, Copper, and Tin-Plate Workers. By Reuben Henry Warn, Practical Tin-Plate Worker. New Edition, Revised and greatly Enlarged by Joseph G. Horner, A.^SI.I.M.E., Author of " Patitrn Making," &c. Crown 8vo, 254 pages, with 430 Illus- trations, ys. 6d., cloth, [j"sf published. Bread anil Biscuit Baking, THE BREAD AND BISCUIT BAKER'S AND SUGAR- BOILER'S ASSISTANT. Including a large variety of Modern Recipes, By Robert Wells, Practical Baker. Crown 8vo, 2s, cloth. " A large number of wrinkles for the ordinarj' cook, as well as the baker."— 5a^2 Review. Confectionery for Hotels and Bestaiirants, THE PASTRYCOOK AND CONFECTIONER'S GUIDE. For Hotels, Restaurants and the Trade in general, adapted also for Family Use. By Robert Wells. Crown 8vo, 2S. cloth. " We cannot speak too highly of this really excellent work. In these days of keen competition otuf readers cannot do better than purchase this hook."— BaAers' Times. Ornamental Confectionery, ORNAMENTAL CONFECTIONERY : A Guide for Bakers, Confectioners and Pastrycooks ; including a variety of Modern Recipes, and Remarks on Decorative and Coloured Work. With 129 Original Designs. By Robert Wells. Crown 8vo, cloth gilt, 55. "A valuable work, practical, and should be in the hands of every baker and confectioner. The Illustrative designs are alone worth treble the amount charged for the whole ■wotk."—Baiers' Times. Flour Confectionery. THE MODERN FLOUR CONFECTIONER. Wholesale and Retail. Containing a large Collection of Recipes for Cheap Cakes, Biscuits, &c. With Remarks on the Ingredients used in their Manufacture. By R. Wells. Crown 8vo, 2s. cloth. Laundry Work. LA UNDRY MANAGEMENT. A Handbook for Use in Private and Public Laundries, Including Descriptive Accounts of Modern Machinery and Appliances for Laundry Work. Small crown 8vo, is. cloth. " This book should certainly occupy an honoured place on the shelves of all housekeepers woo wish to keep themselves au entrant ol the newest appliances and methods."— T/ie Queen. INDUSTRIAL AND USEFUL ARTS. 39 HANDYBOOKS FOR HANDICRAFTS. By PAUL N. HASLUCK, Editor of " Work" (New Series) ; Author of "Lathework," " Millik-q Machines," &c. Crown 8vo, 144 pages, cloth, price is. each. f^ These Hai^dybooks have been u'ritten to supply inforinatioii for VJokkmeu, Students, and Amateurs in the several Handicrafts, on the actual Practice c/ the Workshop, and are intended to convey in plain language Technical Knov/- LEDGE of the several Crafts. ■ In describing the processes employed, and themanipu- lation of material, workshop terms are used ; workshop practice is fully explained; and the text is freely illustrated with drawings of modern tools, appliances, and processes. THE METAL TURNER'S HANDYBOOK. A Practical Manual for Workers at the Foot-Lathe. With over 100 Illustrations. Price is. " The book will be of service alike to the amateur and the artisan turner. It displays thorough knowledge of the subject." — Scotsman. THE WOOD TURNER'S HANDYBOOK. A Practical Manual for Workers at the Lathe. With over ico Illustrations. Price is. "We recommsnd the book to 3'0L;ng turners and amateurs. A multitude of workmen have Utherto sought in yain for a manual of this special industry." — Mechanical World, THE WATCH JOBBER'S HANDYBOOK. A Practical Manual on Cleaning, Repairing., and Adjusting. With upwards of 100 Illustrations. Price IS. "We strongly advise all young persons connected with the watch trade to acquire and study this Inexpensive work."— ClerkenTuell Chronicle, THE PATTERN MAKER'S HANDYBOOK, A Practical Manual on the Constrnction ol Patterns for Founders, With upwards o£ ic-o Illustrations. Price ts. " A most valuable, if not indispensable, manual for the pattern maker." — Knowledge. THE MECHANICS WORKSHOP HANDYBOOK. A Practical Manual on Mechanical Manipulation, Embracing Information on various Handicraft Processes, with Useful Notes and Miscellaneous Memoranda! Comprising about 200 Subjects, Price is. " A very clever and useful book, ivhini should be found in eveiy workshop ; Emd it should ^rtalnly find a place in all technical schools." — Sattirday Review. THE MODEL ENGINEER'S HANDYBOOK. A Practical Manual on the Construction of Model Steam Engines, With upwards of 100 Illustrations. Price is. " Mr. Hasluck has produced a very good little book." — Builder. THE CLOCK JOBBER'S HANDYBOOK. A Practical Manual on Cleaning, Repairing, and Adjusting, With upwards of 100 Illustrations, Price IS. " It is of inestimable service to those commencing the trsiAs."— Coventry Standard, THE CABINET WORKER'S HANDYBOOK : A Practical Manual on the Tools, Materials, Appliances, and Processes employed in Cabinet Work. With upwards of 100 Illustrations. Price is. " Mr. Hasluck's thoroughgoing little Handybook is amongst the most practical guides we hav« seen for beginners in cabinet-work." — Saturday Review. THE WOODWORKER'S HANDYBOOK OF MANUAL IN^ STRUCTION. Embracing Information on the Tools, Materials, Appliances and Processes employed in Woodworking, With 104 Illustrations. Price is, iJust published, THE MET A L WORKER'S HA ND YBOOK, With upwards of 1 00 Illustrations. [In preparation, *.^* Opinions of the Press. " Written by a man who knows, not only how work ought to be done, but how to do it, anS how to convey his knowledge to others." — Engineering. " Mr. Hasluck writes admirably, and gives complete instructions." — Engineer. "Mr. Hasluck combines the experience 01 a practical teacher with the manipulative skill and scientific knowledge of processes of the trained mechanician, and the manuals are marrels of what can be produced at a popular price." — Schoolmaster. " Helpful to workmen of all ages and degrees of experience." — Daily Chronicle " Practical, sensible, and remarkably cheap." — Jotii nal of Education. *' Concise, clear and practical." — Sattirday Review. 4© CROSBY LOCK WOOD &> SON'S CATALOGUE. COMMERCE, COUNTIN G-HOUSE W ORK, TABLES, eie. Vornmercial French. A NEW BOOK OF COMMERCIAL FRENCH : Grammar- Vocabulary — Correspondence — Commercial Documents — Geograpty — Arithmetic— Lexicon. By P. Carroue, Professor in the City High Scbt ol J.— B. tiay (Paris). Crown &vo, 4s. 6rf. cloth. [/'"^ published. Commercial Education, LESSONS IN COMMERCE. By Professor R. Gambaro. of the Royal High Commercial School at Genoa. Edited and Revised by Jasses Gault, Professor of Commerce and Commercial Law in Kind's CoHese, London. Second Edition, Revised. Crown 8vo, 35. 6rf. cloxh. \J list publishrd. " The publisher? of this work have rendered corisiderable service to the cause of commeicial ©iucation by the opportune production ot this volume. . . . The work is peculiarly accepta''"'le to English readers and an admirable addition to existing class-books. In a phrase, we think the trork attains its object in furnishing a brief account of those laws and customs of British trade -wHh vhich the commercial man interested therein should be familiar." — Chainber of Com7yteyceyournaL " An invaluable guide in the hands of those who are preparing for a commercial career." Counting House. Foreign Commercial Correspofidence* THE FOREIGN COMMERCIAL CORRESPONDENT: Beirg Aids to Commercial Correspondence in Five Languages— English, French, German. Italian, and -Spanish. Bv Conrad E. Baker. Second Edition. Crown 8vo, 3s. 6d. cloth. "Whoever wishes to correspond in all the languages mentioned by Mr. Baker cannot do ' Sisan smay this work, the materials of which are excelient and conveniently arranged. They consist cot of entire speciinen letters but — what are far more useful— short passages, sentences, or phrases expressing the same general idea in various torms." — Athe-ris.-nm. "A careful examination has convinced us that it is unusually complete, v.ell arra»iged, axMS reliable. The book is a thorouglily good one." — Schoolmaster. Accounts for Manufacturers, FACTORY ACCOUNTS: Their Principles and Practice. A Handbook for Accountants and Manufacturers, with Appendices on the No- iiienclature of Machine Details ; the Income Tax Acts ; the Rating of Fac- tories ; Fire and Boiler Insurance; the Factory and Workshop Acts, &c., including also a Glossary of Terms and a large number of Specimen Rulings. By Emile Garcke and J. M. Fells, Fo^iirth Edition, Revised and Ed- laiged. Demy 8vo, 250 pages, 6s. strongly bound. •' A verj'interest.ng description of the requirements of Factoiy Accounts. . . . theprincipl* ef- assimilating the Factoi-y Accounts to the general commercial books is one which we thorongiiJy ^^ee with." — Arccunlants' Journal. " Characterised by extreme thoroughness. There are few owners of factories who -would doi 2erlve great benefit from the perusal of this most admirable work."— Z.oca/ Govem^mntCkront^ie. Modern Metrical Units and Systems, MODERN METROLOGY : A Manual of the Metrical Vntti and Systems of the Present Century. With an Appendix containing a proposed English System. By Lowis D'A. Jackson, A.M. Inst. C.E., Author of " Aid to Survey Practice," &c. Large crown 8vo, 12s. 5;?". cloth. " AVe recommend the work to all interested in the practical reform of our weights and icea- Sites. '—AatKre. The Metric System, and the British Standards, A SERIES OF METRIC TABLES, in u^hkh tke British Stand- ard Measures and Weights are compared ivith those of the Metric System at present in Use on the Continent. By C. H. Dowling, C.E. 8vo, ios. 6d. strongly bouud. "Mr. Bowling's Tables are well put together as a re&dy-reckoner for the conversion of on« ^^em into the other." — Aiher.czutn. Iron Shipbuilders' and Merchants' Weight Tables, IRON-PLATE WEIGHT TABLES: For Iron Shiphuildeti. Engineers, and Iron Merchants. Containing the Calculated Weights of up- wards of 150,000 difierent sizes ot Iron Plates, from i foot by 6 in. by \ in. to 10 feet by 5 feet by i in. Worked out on the basis of 40 ibs. to the sqaarf ■ foot of Iron of i inch in thickness. Carefully compiled and thoroughly Fe vised by H. Burlinson and W. H. Simpson, Oblong 4to, 25s. half-bound "This work will be found of great utility. The authors have had much practical experlei>c« 01 what is weuitin^ in making estimates; and the use of the bork ■will save much time in D'akiog elaborate calculanons."— £«i^/iijA Mechanic. COMMERCE, COUNTING-HOUSE WORK, TABLES, etc. 41 -Chiiilivick's Calculator /or JSutnbers and Weights Combined. THE NUMBER, WEIGHT, AND FRACTIONAL CALCU- LATOR. Containing upwards of 250,000 Separate Calculations, showing at a glance the value at 422 difierent rates, ranging from ri«th of a Penny to 20s, each, or per cwt., and £20 per ton, of any number of articles consecu- tively, from I to 470. — Any number of cwts., qrs., and lbs., from 1 cwt. to 470 cwts. — Any number of tons, cwts., qrs., and lbs., from i to 1,000 tons. By William Chadwick, Public Accountant. Third Edition, Revised and Im- proved. 8vo,i8s., strongly bound for Ofl&ce wear and tear. i^c" Is adapted for the use of Accountants and Auditors, Railway Coinpaniei, 'Canal Companies, Shippers, Shipping Agents, General Carriers! etc. Iron/oundets, /Brassfounders, Metal Merchants, Iron Manufacturers, Ironmongers, Engineers, Machinists, Boilet Makers, Millwrights, Roofing, Bridge and Girder Makers, Colliery Proprietors, etc. Timber Merchants, Builders, Contractors, Architects, Surveyors, .Auctioneers, Valuers, Brokers, Mill Owners and Manufacturers, Mill Furnishers, Merchants, and General Wholesale Tradesmen. Also for the Apportionment oj Mileage Charges for Railway Traffic, " It is as easy of reference for any answer or any number of answers as a dictionary, and the references are even more quickly made. For making up accounts or estimates the book must > prove invaluable to all who have any considerable quantity of calculations involving price and •measure in any combination to do." — Engineer. JbLarben's Cofnpreheiisive Weight Calculator, THE WEIGHT CALCULATOR. Being a Series of Tables apon a New and Comprehensive Flan, exhibiting at One Reference the exact Value of any Weight from i lb. to 15 tons, at 300 Progressive Rates, from irf CO 16S5. per cwt., and containing 186,000 Direct Answers, which, with their Combinations, consisting of a single addition (mostly to be performed at sight), will aSord an aggregate of 10,266,000 Answers ; the whole being calcu' lated and designed to ensure correctness and promote despatch. By Henry Harbek, Accountant. Jrifih Edition, carefully Corrected. Royal Svo, £1 5s. strongly half-bcund. iJust published. " A practical and useful work of reference for men of business generally ; It Is the best of the kind we have seen." — IrGnmo7igcr. "Of priceless value to b'asiness men. It is a necessary book !n all mercantile offices."— ^A^- fit Id In-depeiident, Marben^s Comjjrehensive Discount €ruide> THE DISCOUNT GUIDE. Comprising several Series of Tables for the use of Merchants, Manufacturers, Ironmongers, and others, by which may be ascertained the esact Profit arising from any mode of using Discounts, _either in the Purchase or Sale of Goods, and the method of either AUering a Kate of Discount or Advancing a Price, so as to produce, by one operation, a sum that will realise any required profit after allowing one or more Discounts : to which are added Tables of Profit or Advance from i| to go per cent.. Tables of Discount from if to 98! per cent., and Tables of Com- mission, &c., from I to 10 per cent. By Henry Harben, Accountant. New Edition, Revised and Corrected, Demy Svo, 544 pp., £1 5s. half-bound, " A book such as this can only be appreciated by business men, to whom the saving of time Bieaas saving of money V/e have the high authority of Professor J. R, Young that the tables throughout the work are constructed upon strictl}' accurate principles. The work Is a model of typographical clearness, and must prove cf great value to merchants, manufacturers, and general traders." — British 1 rade JournaL, Hiew Wages Calculator. TABLES OF WAGES at 54, 52, 50 and 48 Hours per Week. Showing the Amounts of Wages from One-quarter-of-an-hour to Sixty-four hours in each case at Rates of Wages advancing by One Shilling from 4s. to 55s. per week. By Thos. Garbutt, Accountant. Square crown Svo, 6s. half-bound. [Just published. Iron and Metal Trades' Calculator, THE IRON AND METAL TRADES' COMPANION. For expeditiously ascertaining the Value of any Goods bought or sold by Weight, trom IS. per cwt. to 112s. per owt., and from one farthing per pound to one shilling per pound. By Thomas Downie. 396 pp., 9s. leather. " A most useful set of tables ; nothing like them before s^isted."— Building- Nrais. " Although sjiedally adapted to the iron and metal trades, the tables will be found nseful In every other business In which cjsrchandise Is bougrht and sold by weieht." — Rail-wa^ Ntisis. 42 CROSBY LOCK WOOD &> SON'S CATALOGUE. "DIRECT CALCULATOR S," By M. B. COTSWORTH, of Holgate, York. QUICKEST AND MOST ACCURATE MEANS OF CALCULATION KNOWN. ENSURE ACCURACY and SPEED WITH EASE, SAVE TIME and MONEY. Accounts may be charged out or checked by these means in about one third he time required by ordinary methods of calculation. These unrivalled " Calculators " have very clear and original contrivances for instantly finding the exact answer, by its fixed position, without even sighting the top or side of the page. They are varied in arrange- ment to suit the special need of each particular trade. All the leading firms now use Calculators, even where they employ experts. N.B.— Indicator letters in brackets should be quoted. *' RAILWAY 6- TRADERS' CALCULATOR " (R. & T.) los. 6d. Including Scale of Charges for Small Parcels by Merchandise Trains. " Direct Calculator "—the only Calculator published giving exact charge for Cwts., Qrs. and Lbs., together. " Calculating Tables" for every id. rate to loos. per ton. " Wages Calculator." " Percentage Rates." " Grain, Flour, Ale, &c., Weight Calculators." " DIRECT CALCULATOR (I R) " including all the above except " Calculating Tables." 7s. ''DIRECT CALCULATOR (A)" by ^d., 2.5. each opening, ^act pence to 40s. per ton. 5s. "DIRECT CALCULATOR (B) " by id., 4s. each opening, exact pence to 40s. per ton. 4s. 6d. "DIRECT CALCULATOR (C) " by id. (with Cwts. and Qrs. to nearest farthing), to 40s. per ton. 4s. 6d. "DIRECT CALCULATOR (Ds) " by id. gradations. (Single Tons to 50 Tons, then by fifties to 1,000 Tons, v,-ith Cwts. values below in exact pence payable, fractions oi^d. and upwards being counted as id. 6s. 6d. "DIRECT CALCULATOR (D) " has from 1,000 to 10,000 Tons in addition to the (Ds) Calculator, ys. 6d. "DIRECT CALCULATOR (Es) " by id. gradations. (As (D) to 1,000 Tons, with Cwts. and Qrs. values shown separately to the nearest farthing). 5s. 6d. *' DIRECT CALCULATOR (E) " has from 1,000 to 10,000 Tons in addition to the (Es) Calculator. 6s. 6d. ''DIRECT CALCULATOR (F) " by id., 25. each opening, exact pence to 40s. per ton. 4s. 6d. " DIRECT CALCULATOR (G) " by id., is. each opening ; 6 in. by 9 in. Nearest \d. Indexed (G I) 3s. 6rf. 2S. 6d. " DIRECT CALCULATOR (H) " by i^., is. each opening ; 6 in. by 9 in. To exact pence. Indexed (H I) 3s. 6d. 2s. 6d. "DIRECT CALCULATOR {Yi)'' Showing Values of Tons, Cwts. and Qrs. in even pence (fractions of id. as id.), for the Retail Coal Trade. 4s. 6tf. " RAILWA Y AND TIMBER TRADES MEASURER AND CAL- CULATOR (T)" (as prepared for the Railway Companies). The only book published giving true content of unequal sided and round timber by eight-hs of an inch, quarter girth, Weights from Cubic Feet— Standards, Superficial Feet, and Stone to Weights— Running Feet from lengths of Deals— Standard Multipliers — Timber Measures — Customs Regulations, ikc. 3s. 6d. AGRICULTURE, FARMING, GARDENING, etc. 43 AGRICULTURE, F ARMING, G ARDENING, etc. Dr. Freain's New Edition of ^^ The Standard Treatise on Agriculture.'^ THE COMPLETE GRAZIER, and FARMER'S and CATTLE- BREEDER'S ASSISTANT: A Compendium ol Husbandry. Originally Written by William Youatt. Thirteenth Edition, entirely Re-written, considerably Enlarged, and brought up to the Present Requirements of Agricultural Practice, by William Fream, LL.D., Steven Lecturer in the University of Edinburgh, Author of "The Elements of Agriculture," &c. Royal 8vo, 1,100 pp., with over 450 Illustrations. £1 lis. 6d. strongly and handsomely bound. Extract from Publishers' Advertisement. " A treatise that made its original appearance in tlie first decade of the century, and that enters Bpon Its Thirteenth Edition before the centurj' has run its course, has undoubtedly established its positioii as a work of permanent value. . . The phenomenal progress of the last dozen years in the Practise and Science of Farming has rendered it necessarj^ however, that the volume should be re-written, .... and for this undertaking the publishers were fortunate enough to secure the services of Dr. FREAM, whose high attainments in all matters pertaining to agriculture have been so emphatically recognised by the highest professional and official authorities. In carrying out his editorial duties, Dr. FREA.M has been favoured with valuable contributions by Prof. J. Wortley Axe, Mr. E. Brown, Dr. Bernard Dyer, Mr. w. j. Malden, Mr. R. H. Rew» Prof. Sheldon, Mr. J. Sinclair. Mr. Sanders Spencer, and others. " As regards the illustrations of the work, no pains have been spared to make them as repre- sentative and characteristic as possible, so as to be practically useful' to the Farmer and Grazier." Summary of Contents. Book I. On the Varieties, Breed- ing, P^EARiNG, Fattening, and Management of Cattle. Book II. On the Economy and Man- agement OF THE Dairy. Book III. On the Breeding, Rear- ing, and Management of Horses. Book VII. On the Breeding, Rear- ing, and Management of Poultry, Book VIII. On Farm Offices and Implements of Husbandry. Book IX. On the Culture and Man- agement of Grass Lands. Book X, On the Cultivation and Book IV. On the Breedi^ng, Rear- ' Application of Grasses, Pulse, AND Roots. Book XI. On Manures and their Application toGrass Land&Crops Book XII. Monthly Calendars or iNG, AND Fattening of Sheep. Book V. On the Breeding, Rearing, AND Fattening of Swine. Book VI. On the Diseases of Live Stock. i Farmwork. *^* Opinions of the Press on the New Edition, " Dr. Fream is to be congratulated on the successful attempt he has made to give us a work which will at once become the standard classic of the farm practice of the country. We believe that it will be found that it has no compeer among the many works at present in existence. . ." . The illustrations are admirable, while the frontispiece, which represents the well-known bull, New Year's Gift, bred by the Queen, is a v.'ork of art."— TVze Times. " The book must be recognised as occupying the proud position of the most exhaustive work of reference in the English language on the subject with which it deals." — AthenaiiTn. " The most comprehensive guide to modern farm practice that exists in the English language to-day. . . . The book is one that ought to be on every farm and in the library of every land- owner."— Afar-^ Lane Express. " In point of exhaustiveness and accuracy the work wiU certainly hold a pre-eminent and unique position among books dealing -nnth scientific agricultural practice. It is, in fact, an agri- cultural library of itself."- No;-th British Agnnilturist. " A compendium of authoritative and well-ordered knowledge on every conceivable branch the work of the live stock farmer ; probably without an equal in this or any other countrj-." Yorkshire Post, British Farm Live Stock, FARM LIVE STOCK OF GREAT BRITAIN. By Robert Wallace, F.L.S., F.R.S.E., &c., Professor of Agriculture and Rural Eco- nomy in the University of Edinburgh. Third Edition, thoroughly Revised and considerably Enlarged. With over 120 Phototypes of Prize Stock. Demy 8vo, 384 pp., with 79 Plates and Maps, 12s, 6d, cloth. _A really complete work on the history, breeds, and m.anagement of the farm stock of Great Britain, and one which is likely to find its way to the shelves of everj- country gentleman's library." — The Times. " The latest edition of ' Farm Live Stock of Great Britain ' is a production to be proud of, and Its Issue not the least of the services which its author has rendered to agricultural science." Scottish Farmer, - " The book is very attractive . . . and we can scarcely imagine the existence of a farmer who would not like to have a copy of this beautiful •vioxV.:'>—Mark Lane Express. " A work which v^ill long be regarded as a standard authority whenever a concise history and - description of the breeds of live stock in the British Isles is required. '—EelVs Weekly Messenger 44 CROSBY LOCKWOOD &• SON'S CATALOGUE. Dairy Farttiiiig» BRITISH DAIRYING. A Handy Volume on the Work of the Dairy-Farm. For the Use of Technical Instruction Classes, Students in Agricultural Colleges, and the Working Dairy-Farmer. By Prof.J.P. Sheldon, late Special Commissioner of the Canadian Government, Author of " Dairy Farming," &c. With numerous Illustrations. Crown 8vo, 25. 6d. cloth. " We confidently recommend it as a text-book on dairj- farming." — Agricultural Gazette. " Probably the best half-crown manual on dairy work that has yet been produced."— A'ijr/A British Agriculturist. " It is the soundest little work we have yet seen on the subject."— 7"^e Tiiyics, Dairy Manual, MILK, CHEESE AND BUTTER: A Practical Handbook on their Properties and the Processes of their Production, including a Chapter on Cream and the Methods of its Separation from Milk, By John Oliver, late Principal of the Western Dairy Institute, Berkeley. With Coloured Plates and 200 Illusts. Crown Svo, 7S.6d. cloth, IJust published. "All exhaustive and masterly prcduction. It maj' be cordially recommended to all students and practitioners of dairy science.'' — A'.B. Agriculturist. " We strong 1}' recommend this very comprehensive and carefully- written book to dairj--farmers -and students of dairying. It is a distinct acquisition to the library of the agriculturist."— ^i^»-icwA iural Gazette. Agricultural Facts and Figures, NOTE-BOOK OF AGRICULTURAL FACTS AND FIGURES FOR FARMERS AND FARM STUDENTS. By Primrose McConnell, B.Sc. Fifth Edition. Royal same, roan, gilt edges, with band, 4s. " Literallj' teems with information, and we can cordially recommend It to cJl connected ^th -agriculture."— A^iM-^A British A£rriculturist. Small Farming, SYSTEMATIC SMALL FARMING; or, The Lessons of my Fa7in. Being an Introduction to Modern Farm Practice for Small Farmers. By R. Scott Burn. With numerous Illustrations, crown SvOj 6s. cioth. "This Is the completest book of Its class we have seen, and one which every amateur fanncf Trill read with pleasure and accept as a guide. "—Fie/o?. Modem Farming, OUTLINES OF MODERN FARMING. By R. Scott Burn. Soils, Manures, and Crops— Farming and Farming Economy— Cattle, Sheep, and Horses — Management of Dairy, Pigs, and Poultry — Utilisation of Town-Sewage, Irrigation, &c. Sisth Edition. In One Vol., 1.250 pp., baif^ bound, profusely Illustrated, i2S, " The aim of the author has been to make his work at once comprehensive and trustworthy and he has succeeded to a degree which entitles him to much credit." — Mornins Advertiser, Agricultural Engineering, FARM ENGINEERING, THE COMPLETE TEXT-BOOK OF, Comprising Draining and Embanking; Irrigation and Water Supply ; Farm Roads, Fences, and Gates ; Farm Buildings ; Barn Implements and Ma- chines ; Field Implements and ^Machines; Agricultural Surveying, &c. By Prof. John Scott, 1,150 pages, half-bound, with over 600 Illustrations, izs, " Written with great care, as well as with knowledge and ability. The author hsis done his ^-ork well ; we have found him a very trustworthy guide wherever we have tested his statements. ^^e volume wU be of great value to agricultural students," — Mark Lane Exitress, Agricultural Text-Book, THE FIELDS OF GREAT BRITAIN : A Text-Book of Agriculture, adapted to the Syllabus of the Science and Art Department. For Elementary and Advanced Students. By Hugh Clements (Board of Trade). Second Edition, Revised, with Additions. iSmo, zs. 6d. cloth "A most comprehensive volume, giving a mass of information." — Agricultural Eccnomtst. "It is a long time since we have seen a book which has pleased us more, or which contalnj • stjch a vast and useful fund of knowledge." — Educational lirnes. Tables for Faj'nierSf etc, TABLES, MEMORANDA, AND CALCULATED RESULTS for Farmers, Graziers, Agricultural Students, Surveyors, Land Agents, Auc- tioneers, etc. With a New System of Farm Book-keeping, By Sidney Fran- cis. Third Edition, Revised. 272 pp., waistcoat-pocket size, is. 6d. leather. "Weighing less than i oz., and occupying no more space than a match box, It contains a mass of facts and calculations which has never before, in such handy form, been obtainable. Every operation on the farm is dealt with. The work may be taken as thoroughly accurate, the whole • of the tables having been revised by Dr. Fream. We cordially recommend it." — Bcirs H'eekly ■ Messenetr AGRICULTURE, FARMING. GARDENING, etc. 45 Artificial 3Ianures (Hid Foods, FERTILISERS AND FEEDING STUFFS: Their Proper- ties and Uses. A Handbook for the Practical Farmer. By Bernard Dver, D.Sc. (Lond.) With the Text of the Fertilisers and Feeding Stuffs Act of 1893, the Regulations and Forms of the Board of Agriculture and Notes on the'Act by A. J, David, B.A., LL.M., of the Inner Temple, Barrister-at-Law. Crown 8vo, 120 pages, is. cloth. [Jtist published. " An excellent shilling's worth. Dr. Dyer has done farmers good service in placing at their dis- posal so much useful information in so intelligible a form." — The Times. The Management of Bees, BEES FOR PLEASURE AND PROFIT: A Guide to the Manipulation of Bees, the Production of Honey, and the General Manage- ment of the Apiary. By G. Gordon Samson. Crown Svo, is. cloth, " The intending bee-keeper will find exactly the kind of information required to enable him to make a successful start with his hives. The author is a thoroughly competent teacher, and his book may be commended." — Mor7iing Post. Farm and Estate Book-keeping, BOOK-KEEPING FOR FARMERS & ESTATE OWNERS. A Practical Treatise, presenting, in three Plans, a System adapted for all Classes of Farms, By Johnson M.Woodman, Chartered Accountant. Second Edition, Revised. Crown Svo, 3s. 6d. cloth boards ; or 2s. 6d. cloth limp. " The volume is a capital study of a most important subject." — A^ric^iliur-al Gazette. The young farmer, land agent, and surveyor will find Mr. Woodman's treatise more than repay its cost and stwAy.'—Binldnis- News. Farm Account Book, WOODMAN'S YEARLY FARM ACCOUNT BOOK. Giving a Weekly Labour Account and Diary, and showing the Income and Expen- diture under each Department of Crops, Live Stock, Dairy, &c. &c. With Valuation, Profit and Loss Account, and Balance Sheet at the end of the Year. By Johnson M. Woodman. Chartered Accountant, Author of" Book- keeping for Farmers." Folio, 7s. 6d. half bound. Iculture "Contains every requisite form for keeping farm accounts readily and accurately." A^r-i- Early Fruits, Flowers, and Vegetables, THE FORCING GARDEN ; or, How to Grow Early Fruits, Flowers, and Vegetables. With Plans and Estimates for Building Glass* houses, Pits, and Frames. B^. Samuel Wood. Crown Svo, 3s. 6d. cloth. " A good book, and fairly fills a place that was in some degree vacant. The book is written with great care, and contains a great deal of valuable teaching. ' ' — Garderiers' Magazine. Good Gardening, A PLAIN GUIDE TO GOOD GARDENING ; or, How to Grow Vegetables, Fruits, and Flowers. By S. Wood. Fourth Edition, with con- siderable Additions, &c., and numerous Illustrations. Crown Svo, 3s. 6d. cl, "A very good book, and one to be highly recommended as a practical guide. The practical directions are excellent." — Athenczu'tn. " May be recommended to young gardeners, cottagers, and specially to amateurs, for the plain, simple, and trustworthy information it gives on common matters too often neglecter'."— Gardenen' Chronicle, Gainful Gardening, MULTUM-IN-PARVO GARDENING; or, How to make One Acre of Land produce £620 a-year by the Cultivation of Fruits and Vegetables ; also. How to Grow Flowers in Three Glass Houses, so as to realise £176 per annum clear Profit. By Samuel Wood, Author of "Good Gardening," &c. Fifth and Cheaper Edition, Revised, with Additions, Crown Svo, is. sewed. "We are bound to recommend it as not only suited to the case of the amateur and gentleman's gardener, but to the market grower." — Gardeners' Magazine, Gardening for Ladies, THE LADIES' MULTUM-IN-PARVO FLOWER GARDEN, and Amateurs' Complete Guide. With Illusts. By S. Wood. Cr.Svo, 3s. 6d. cl. Seceipts for Gardeners, GARDEN RECEIPTS. Edited by Charles W. Quin. i2mo, IS. 6d. cloth limp. Market Gardening, MARKET AND KITCHEN GARDENING. By Contributors to "The Garden." Compiled by C. W. Shaw, late Editor of "Gardening Illustrated." i2mo 3s. 6d. cloth boards. 46 CROSBY LOCK WOOD 6- SON'S CATALOGUE. AUCTIONEERING, VALUING, LAND SURVEYING ESTATE AGENCY, etc. Auctioneer's Assistant. THE APPRAISER., A UCTIONEER, BROKER, HOUSE AND ESTATE AGENT AND VALUER'S POCKET ASSISTANT, for theValua- tion for Purchase, Sale, or Renewal of Leases, Annuities and Reversions, and of property generally; with Prices for Inventories, &c. By John Wheeler, Valuer, &c. Sixth Edition, Re-written and greatly extended by C. Norris, Surveyor, Valuer, &c. Royal 32mo, 5s. cloth. " A neat and concise book of reference, containing: an admirable and clearly-arranged list ol prices for inventories, and a very practical guide to detemiine the value of {umituTe.&c."—SUxndard, " Contains a large quantity of varied and useful information as to the valuation for purchase, sale, or renewal of leases, annuities and reversions, and of property generally, with prices foi Inventories, and a guide to determine the value of interior fittings and other effects.'' — Builder. A uctioneering, AUCTIONEERS: THEIR DUTIES AND LIABILITIES. A Manual of Instruction and Counsel for the Young Auctioneer. By Robert Squibbs, Auctioneer, Second Edition, Revised and partly Re-written, Demy 8vo, I2S. 6d. cloth, *** Opinions of the Press. " The standard text-book on the topics of which it treats."— A thettcButn. " The work is one of general excellent character, and gives much information in a compeo- dious and satisfactory iotm."—Btnlder. " May be recommended as giving a great deal of information on the law relating to auctioneers, in a very readable form." — LaTv Jo7irnal. " Auctioneers may be congratulated on having so pleashig a writer to minister to their special Iiee(iS."-~Solicieors' Joiimal. "Every auctioneer ought to possess a copy of this excellent ■fiQx)g.:'— Ironmonger . " Of great value to the profession. . . . We readily welcome this book from the fact that It treats the subject in a manner somewhat new to the profession.'' — Estates Gazette. Inwood's Estate Tables, TABLES FOR THE PURCHASING OF ESTATES, Freehold, Copyhold, or Leasehold; Annuities, A dvowsons, etc., and for the Renewing of Leases held under Cathedral Churches, Colleges, or other Corporate bodies for Terms of Years certain, and for Lives : also for Valuing Reversionary Estates, Deterred Annuities, Next Presentations, &c. ; together with Smart's Five Tables of Compound Interest, and an Extension of the same to Lower and Intermediate Rates. By W. Inwood. 24th Edition, with considerable Additions, and new and valuable Tables of Logarithms for the more Difl5cnlt Computations of the Interest of Money, Discount, Annuities, &c. , by M. Fbdob Thoman, of the Scciete Credit Mobilier ot Pans. Crown 8vc, Ss. cloth. "Those interested in the purchase and sale of estates, and in the adjustment of compensatloa cases, as well as in transactions in annuities, life insurances, &c., will find the present edlHon o# eminent service. ' '—Engineering. " ' Inwood's Tables ' still mamtain a most enviable reputation. The new Issue has been enriched by arge additional contributions by M. Fedor Thoman, whose carefully arranged Tables caonot fail to be of the utmost utility." — Minifig Journal, Agricultural Valuer's Assistant, THE AGRICULTURAL VALUER'S ASSISTANT. A Prac tical Handbook on the Valuation of Landed Estates ; including Rules and Data for Measuring and Estimating the Contents, Weights, and Values of Agricultural Produce and Timber, and the Values of Feeding Stuffs, Manures, and Labour ; with Forms of Tenant-Right-Valuations, Lists of Local Agricultural Customs, Scales of Compensation under the Agricultural Holdings Act, &c. &c. By Tom Bright, Agricultural Surveyor. Second Edition, much Enlarged. Crown 8vo, 5s. cloth. ■ ' Full of tables and examples in connection with the valuation of tenant-right, estates, laboni. contents, and weights of timber, and farm produce of all kinds."— yigriculiural Gazette. " An eminently practical handbook, full of practical tables and data of undoubted interest and value to surveyors and auctioneers in preparing valuations of all kinds."— Farw^r. Plantations and Underwoods, POLE PLANTATIONS AND UNDERWOODS: A Practical Handbook on Estimating the Cost of Forming, Renovating, Improving, and Grubbing Plantations and Underwoods, their Valuation for Purposes ol Transfer, Rental, Sale, or Assessment. By Tom Bright, Author of •'The AgriculturalValue: s Assistant." &c. Crown Svo, 3s, &d, cloth. " To valuers, foresters and zigents it will be a welcome aid." — North British Agriculturist. "Well Ccilculated to assist the valuer in the discharge of his duties, and of undoubted lnt«»e«i and use both to surveyors cind auctioneers In Dreparing valuations of all kinds." — Kent Heboid. AUCTIONEERING, VALUING, LAND SURVEYING, etc. 47 Hudson's Land yaluer's Jt*ocicet-Book, THE LAND VALUER'S BEST ASSISTANT: Being Tables on a very much Improved Plan, for Calculating the Value of Estates. With Tables for reducing Scotch, Irish, and Provincial Customary Acres to Statute Measure. &c. By R. Hudson, C.E. New Edition. Royal 32mo. 4s. leather. " Of incalculable value to the country gentleman and professional m3Ln:'—Far>fiers' Jotirnal, Bwart's Land Improver^s Pocket-Book, THE LAND IMPROVER'S POCKET-BOOK OF FORMULA, TABLES, and MEMORANDA required in any Computation relating to the Permanent Improvement of Landed Property. By John Ewart, Surveyor. Second Edition. Royal 32mo, 4s. leather. Complete Agricultural Surveyor's JPocket-Book, THE LAND VALUER'S AND LAND IMPROVER'S COM- PLETE POCKET-BOOK. Being of the above Two Works bound together. Leather, with strap, ys. 6d. Mouse Property^ HANDBOOK OF HOUSE PROPERTY. A Popular and Practi- cal Guide to the Purchase, Mortgage, Tenancy, and Compulsorv Sale of Houses and Land, including the Law of Dilapidations and Fixtures ; with Examples of all kinds of Valuations, Useful Information on Building, and Suggestive Elucidations of Fine Art. By E. L. Tarbuck, Architect and Surveyor. Fifth Edition, Enlarged. lamo, 5s. cloth. " The advice Is thoroughly practical."— Z-a;?^ y' inspectors. The work is replete with Information."— Z(7ca/ Government Journal. MODERN JOURNALISM. A Handbook of Instruction and Counsel for the Young Journalist, By John B. Mackie, Fellow of the Insti- tute of Journalists. Crown 8vo, 2s. cloth. {Just published. ' This invaluable guide to journalism is work which all aspirants to a journalistic career will read with advantage." — Journalist. Private Bill Legislation and Provisional Orders, HANDBOOK FOR THE USE OF SOLICITORS AND EN- GINEERS Engaged in Promoting Private Acts of Parliament and Provi- sional Orders, for the Authorization of Railways, Tramways, Gas and Water Works, &c. By L. Livingston Macassey, of the Middle Temple, Barrister- at-Law, M.Inst.C.E. Svo, 25s. cloth. Law of Patents, PATENTS FOR INVENTIONS, AND HOW TO PROCURE THEM. Compiled for the Use of Inventors, Patentees and others. By G. G. M. Hardingham, Assoc. Mem.Inst.C.E., &c. Demy Svo, is, 6d. cloih. Labour Disputes, CONCILIATION AND ARBITRATION IN LABOUR DIS- PUTES : A Historical Sketch and Brief Statement of the Present Position of the Question at Home and Abroad. By J. S. Jeans, Author of "England's Supremacy," &c. Crown Svo, 200 pp., 2S, 6d. cloth. [Just published, " Mr. Jeans is well qualified to write on this subject, both by his previous books and by his practical experience as an arbitrator."— r/fe Times, 48 CROSBY LOCKWOOD S' SON'S CATALOGUE. A Complete Epitome of the Laws of this Country, EVERY MAN'S OIVN LAWYER: A Handy-Book of the Principles of Law and Equity. With A CONCISE DICTIONARY OF LEGAL TERMS. By A Barrister. Thirty-third Edition, carefully Revised, and including New Acts of Parliament ot 1S95. Ccmorising the Summary jurisdiction {Married Women.) Act, 1895 (giving to Ma-^istrates largely increased powers for the Protection of ill-used Wives), as well as- new enactments comprised in the Factory and Woikshop Act, 1S95 ; Law of Distress Amendment Act, 1895; Corrupt and Illegal Practices Act, 1895 r Local Government Act, 1894 (establishing District and Parish Councils); Finance Act, 1894 (imposing the New Death Duties) ; Prevention of Cruelty to Children Act, 1894; Married Women's Property Act, 1803; Betting and Loans (Infants) Act, 1892; with many other Acts of recent years. Crown 8vo, 750 pp., price 6s. M. (saved at every consultation!) strongly bound in cloth. [Just published, *** The Book will be found to comprise (amongst other matter)— The Rights and Wrongs of individuals— Landlord and Tenant— Vendors AND Purchasers— Leases and Mortgages— principal and Agent— Partnership AND companies— Masters, Servants, and workmen— Contracts and agreements —borrowers, Lenders, and Sureties— Sale and Purchase of Goods-Cheques, Bills, and notes-Bills of Sale— Bankruptcy- Railway and Shipping Law- Life, Fire, and ivLarine Insurance— accident and Fidelity' Insurance— Criminal Law— Parliamentary- Elections— County Councils— District Councils— Parish Councils— municipal Corporations — Libel and Slander— public Health and Nuisances— Copyright, Patents, Trade Marks— Husband and wife— Divorce— Infancy— custody of Children — Trustees and Executors- Clergy, Church- wardens, ETC.— Game La.w3 and Sporting- Innkeepers— horses and Dogs— Taxes and death duties— forms of Agreements, Wills, Codicils, Notices, etc. tS" The object of this work is to enable those who consult it to help them- selves to the law; and thereby to dispense, as far as possible, with professional assistance and advice. There are many wrongs and grievances which persons sub- mit to from time to time through not knowing how or where to apply for redress ; and many persons have as great a dread of a lawyer's office as of a lion's den. With this book at hand it is believed thatma.ny a Six-and-Eightpence may be saved ; many a wrong redressed ; many a right reclaimed; many a law suit avoided ; and many an evil abated. The work has established itself as the standard legal adviser of all classes, and has also made a reputation for itself as a useful book of reference for lawyers residing at a distance from law libraries, who are glad to have at hand a work embodying recent decisions and enactments, •** Opinions of the Press, "The amount of information squaezed into this volume is wonderful." — iaa/ youniat (Feb. 8, 189 ,. "A complete code of English Law, written in plain language, which all can understand. Should be in the hands of every business man, and all who wish to abolish lav/yers' bills. . , '■*^ukly Times, "A complete digest of the most useful facts which constitute English \-a.\v."— Globe. "Admirably done, admirably arranged, and admirably cheap.'' — Leeds Mercury. " A concise, cheap and complete epitome of the English law. So plainly written that he who runs mav read, and he who reads may understand." — Figaro. " The ' Concise Dictionary ' adds considerably to its value. — Westminster Gazette. " A complete epitome of the law ; thoroughly intelligible to non-professional readers." Bei:'s Life, Legal Guide for Pawnbrokers, THE LAW OF LOANS AND PLEDGES. With Statutes and a Digest of Cases. By H. C. Folkard, Esq., Barrister-at-Law. Fcap. 8vo, 3s. 6d. cloth. The Law of Contracts, LABOUR CONTRACTS : A Popular Handbook on the Law of Contracts for Works and Services. By D. Gibbons. Fourth Edition, with Appendix of Statutes by T. F. Uttley, Solicitor. Fcap. 8vo, 3^. 6d. clotb. The Factory Acts. SUMMARY OF THE FACTORY AND WORKSHOP ACTS (1878-1891). For the Use of Manufacturers and Managers. By Emile Garcke and J. M. Fells. (Reprinted nrom " Factory Accounts.") Crown 8vo, 6d. sewed. OQDBN, SMALE AND CO. LIMITBD, PRINTERS, GREAT SAFPBON HTLL. E C. WEALE'S SERIES SCIENTIFIC AND TECHNICAL WORKS. "It is not too much to say that no books have ever proved more popular with or more useful to young engineers and others than the excellent treatises comprised in Weale's Series." — Engineer. ^ H^ta Classt&& list. PAGE CIVIL ENGINEERING AND SURVEYING 2 MINING AND METALLURGY .... 3 MECHANICAL ENGINEERING .... 4 NAVIGATION, SHIPBUILDING, ETC. . 5 PAGE ARCHITECTURE AND BUILDING . . 6 INDUSTRIAL AND USEFUL ARTS. . 9 AGRICULTURE, GARDENING, ETC. . 10 MATHEMATICS, ARITHMETIC, ETC. . 12 BOOKS OF REFERENCE AND MISCELLANEOUS VOLUMES . . 14 CROSBY LOCKWOOD AND SON, 7, STATIONERS' HALL COURT, LONDON, E.G. 1897. 2 weale's scientific and technical series. CIVIL ENGINEERING & SURVEYING. Civil Engineering. By Henry Law, M. Inst. C.E. Including a Treatise on Hydraulic Engineerixg by G. R. Burnell, M.I. C.E. Seventh Edition, revised, with Large Additions by D. K. Cl.'lrk, M.I. C.E. . . . 6/6 Pioneer Engineering : A Treatise on the Engineering Operations connected with the Settlement of Waste Lands in New Countries. By Edward Dobson, A. I. C.E. With numerous Plates. Second Edition ... ... 4/6 Iron Bridges of Moderate Span : Their Construction and Erection. By Hamilton W. Pendred. With 40 Illustrations 2/0 Iron (Application of) to the Construction of Bridges, Roofs, and other ISTorks. By Francis Campin, C.E. Fourth Edition ...... 2/6 Constructional Iron and Steel ISTork, as applied to Public, Private, and Domestic Buildings. By Francis Campin, C.E 3/6 Tubular and other Iron Girder Bridges. Describing the Britannia and Conway Tubular Bridges. By G. Drysdalk Dempsey, C.E. Fourth Edition 2/0 Materials and Construction : a Theoretical and Practical Treatise on the Strains, Designing, and Erec tion of Works of Construction. By Francis Campin, C.E. . 3/0 Sanitary Y/ork in the Smaller Towns and in Villages. By Charles Slagg, Assoc. M. Inst. C.E. Second Edition . . 3/0 Roads and Streets (The Construction of). In Two Parts : I. The Art of Constructing Common Roads, by H. Law, C.E., Revised by D. K. Clark, C.E. ; II. Recent Practice : In- cluding Pavements of Wood, Asphalte, etc. By D. K. Clark, C.E. 4/6 Gas ^STorks (The Construction of), And the Manufacture and Distribution of Coal Gas. By S. Hughes, C.E. Re- wrirten by William Richards, C.E. Eighth Edition . . 5/6 "Water "Works For the Supply of Cities and Towns. With a Description of the Principal Geological Formations of England as influencing Supplies of Water. By Samuel Hughes, F.G.S., C.E. Enlarged Edition . . . . 4/0 The PoTsrer of ISTater, As applied to drive Flour Mills, and to give motion to Turbines and other Hj-drostatic Ena;ines. By Joseph Glynn, F.R.S. New Edition . 2/0 ISTells and ^Well-Sinking. By John Geo. Swindrll, A.R.I.B.A., and G. R. Burnell, C.E. Revised Edition. With a New Appendix on the Qualities of Water. Illustrated 2/0 The Drainage of Lands, To-wns, and Buildings. By G. D. Demi'Sey, C.E. Revised, with large Additions on Recent Practice, by D. K. Clark, M.I.CE. Second Eition, corrected . 4/6 Embanking Lands from the Sea. With Pariiculars of actual Embankments, S:c. By John Wiggins . 2/0 The Blasting and Quarrying of Stone, For Building and other Purposes. With Remarks on the Blowing up of Bridges. By Gen. Sir J. Eurgovne, K.C.B 1/6 Foundations and Concrete Works. With Practic.'il Remarks on Footings, Planking, Sand, Concrete. B^ton, Pile-driving, Caissons, and Cofferdams. By E. Dobson, M.R.I.B.A. Seventh Edition • • • 1 /6 WEALES SCIENTIFIC AND TECHNICAL SERIES. 3 Pneumatics, Including Acoustics and the Phenomena of Wind Currents, for the Use of Beginners. By Charles Tomlinson, F.R.S. Fourth Edition . 1/6 Land and Engineering Surveying. For Students and Practical Use. By T. Baker, C.E. Fifteenth Edition, revised and corrected by J. R. Young, formerly Professor of Mathematics, Belfast College. Illustrated with Plates and Diagrams . . . 2/0 Mensuration and Measuring. For Students and Practical Use. With the jNIensuration and T,evelling of Land for the purposes of Modern Engineering. By T. Baker, C.E. New Edition by E. Nugent, C.E, ... .... 1 /6 MINING AND METALLURGY. Mineralogy, Rudiments of. By A. Ramsay, F.G.S. Third Edition, revised and enlarged. Woodcuts and Plates . . . . . . . .3/6 Goal and Goal Mining, A Rudimentary Treatise on. By the late Sir Warington W. Smyth, F.R.S. Seventh Edition, revised and enlarged 3/6 Metallurgy of Iron. Containing Methods of Assay, Analyses ©f Iron Ores, Processes of Manu- facture of Iron and Steel, &c. By H. Bauerman, F.G.S. With numerous Illustrations. Sixth Edition, revised and enlarged . . . -5/0 The Mineral Surveyor and Valuer's Gomplete Guide. By W. Lintern. Third Edition, with an Appendix on Magnetic and Angular Surveying 3/6 Slate and Slate Quarrying: Scientific, Practical, and Commercial. By D. C. Davies, F.G.S. With numerous Illustrations and Folding Plates. Third Edition . . 3/0 A First Book of Mining and Quarrying, with the Sciences connected therewith, for Primary Schools and Self In- struction. By J. H. Collins, F.G.S. Second Edition . . .1/6 Subterraneous Surveying, with and without the Magnetic Needle. By T. Fenwick and T. Baker, C.E. Illustrated 2/6 Mining Tools. Manual of. By William Morgans, Lecturer on Practical Mining at the Bristol School of Mines 2/6 Mining Tools, Atlas of Engravings to Illustrate the above, containing 235 Illustrations of Mining Tools, drawn to Scale. 4to. ........ 4/6 Physical Geology, Partly based on Major-General Portlock's " Rudiments of Geology." By Ralph Tate, A.L.S., &c. Woodcuts 2/0 Historical Geology, Partly based on Major-General Portlock's " Rudiments." By Ralph Tate, A.L.S., &c. Woodcuts 2/6 Geology, Physical and Historical. Consisting of " Physical Geology," which sets forth the Leading Principles of the Science ; and " Historical Geology--," which treats of the Mineral and Organic Conditions of the Earth at each successive epoch. By Ralph Tate, F.G.S 4/6 Electro-Metallurgy, Practically Treated. By Alexander Watt. Ninth Edition, enlarged and revised, including the most Recent Processes .... 3/6 WEALES SCIENTIFIC AND TECHNICAL SERIES. MECHANICAL ENGINEERING. The Y/orkman's Manual of Engineering Drawing. By John Maxton, Instructor in Engineering Dra'AJng, Royal Naval College, Greenwich. Seventh Edition. 300 Plates and Diagrams . 3/6 Fuels : Solid, Liquid, and Gaseous. Their Analysis and Valuation. For the Use of Chemists and Engineers. By H. J. Phillips, F.C.S., formerly Analytical and Consulting Chemist to the Great Eastern Railway. Second Edition, Revised . . . 2/0 Fuel, Its Combustion and Economy. Consisting of an Abridgment of " A Treatise on the Combustion of Coal and the Prevention of Smoke." By C. W. Williams, A.I.C.E. With Exten- sive Additions by D. K. Clark, M. Inst. CE. Third Edition . 3/6 The Boilermaker's Assistant in Drawing, Templating, and Calculating Boiler Work, &c. By J. Court- ney, Practical Boilermaker. Edited by D. K. Clark, C.E. . 2/0 The Boiler-Maker's Ready Reckoner, with Examples of Practical Geometry and Templating for the Use of Platers, Smiths, and Riveters. By John Courtney. Edited by D. K. Clark, M.I. C.E. Second Edition, revised, with Additions . . 4-/0 %* T^ last two IVorks in One Volume, half-bound, entitled " The Boiler- maker's Ready-Reckoner and Assistant." By J. Courtney and D. K. Clark. Price 7s. Steam Boilers : Their Construction and Management. By R. Armstrong, C. E. Illustrated 1/6 Steam and Machinery Management. A Guide to the Arrangement and Economical Management of Machinery. By M. Powis Bale, M. Inst. M.E 2/6 Steam and the Steam Engine, Stationary and Portable. Being an Extension of the Treatise dn the Steam Engine of Mr. J. Sewell. By D, K. Clark, C.E. Third Edition 3/6 The Steam Engine, A Treatise on the Mathematical Theory of, with Rules and Examples for Practical Men. By T. Bakkr, C.E 1/6 The Steam Engine. By Dr. Lardner. Illustrated . .1/6 LocomotiYe Engines, By G. D. Dempsey, C.E. With large Additions treating of the J.Iodern Locomotive, by D. K. Clark, M. Inst. C.E. . . . . , 3/0 LocomotiYe Bngine-Driving. A Practical Manual for Engineers in charge of Locomot-ive Engines. By Michael Reynolds. Eighth Edition. 3^-. 6d. limp ; cloth boards 4/6 Stationary Engine-Driving. A Practical Manual for Engineers in charge of Stationary Engines. By Michael Reynolds. Fourth Edition. 3J. 6^7V« ds. WEALES SCIEJ^TiFIG AND TECHNICAL SERIES. INDUSTRIAL AND USEFUL ARTS. Cements, Pastes, Glues, and Gums. A Practical Guide to the Manufacture and Application of the various Agglutinants required for Workshop, Laboratory, or Office Use. Wiih upwards of 900 Recipes and Formulic. By H. C. Standage . . 2/0 Clocks and Watches, and Bells, A Rudimentary Treatise on._ By Sir Edmund Beckett, Q.C. (Lord Grimthorpe). Seventh Edition . 4/6 The Goldsmith's Handbook. Containing full Instructions in the Art of Alloying, l^relting, Reducing, Colouring, Collecting and Refining, Recovery of Waste, Solders, Enamels, &c., &c. By George E. Gee. Third Edition, enlarged . . . 3/0 The Silversmith's Handbook, On the same plan as the Goldsmith's Handbook. By George E. Gee. Second Edition, Revised 3/0 ■*^* The last tzvo IVgrks, in One handsome Vol. , half-hound, "js. The Hall-Marking of Jewellery. Comprising an account of all the different Assay Towns of the United Kingdom; with the Stamps and Laws relating to the Standards and Hall- ]\Iarks at the various Assay Offices. By George E. Gee . . 3/0 Practical Organ Building. By W. E. Dickson, M.A. Second Edition, Revised, with Additions 2/6 Coach-Building : A Practical Treatise. By James W. Burgess. With 57 Illustrations 2/6 The Brass Founder's Manual: Instructions for Modelling, Pattern Making, Moulding. Turning, &c. By W. Graham 2/0 The Sheet-Metal Ifforker's Guide. A Practical Handbook for Tinsmiths, Coppersmiths, Zincworkers, &c., with 46 Diagrams. By W. J. E. Crane. Second Edition, revised . 1 /6 SeiBffing Machinery: Its Construction, History, &c. With full Technical Directions for Adjust- ing, &c. By J. W. Urquhart, C.E 2/0 Gas Fitting : A Practical Handbook. By John Black. Second Edition, Enlarged. With 130 Illustrations . . 2/6 Construction of Door Locks. From the Papers of A. C. HohBS. Edited by Charles Tomlinson, F.R.S. With a Note upon Iron Safes by Robert Mallet. Illustrated . 2/6 The Model Liccomotiire Engineer, Fireman, and Engine-Boy. Comprising an Historical Notice of the Pioneer Locomotive Engines and their Inventors. By Michael Reynolds. Second Edition. With numerous Illustrations, and Portrait of George Stephenson . . 3 6 The Art of Lietter Painting made Easy. By J. G. Bauenoch. With 12 full-page Engravings of Examples . "J jQ The Art of Boot and Shoemaking. Including Measurement, Last-fitting, Cutting-out, Closing and Making. By John Bedford Lend. With numerous Illustrations. Third Edition 2/0 Mechanical Dentistry : A Practical Treatise on the Construction of the Various Kinds of Artificial Dentures. By Charles Hunter. Third Edition, revised . .3/0 l^ood Engraving: A Practical and Easy Introduction to the Art. By W. N. Brown . 1 /6 Laundry Management. A Handbook for Use in Private and Public Laundries. Including Accounts of Modern Machinery and Appliances. By the Editor of " The Laundry Journal." With numerous Illustrations. Second Edition . , 2/0 10 weale's scientific and technical series. AGRICULTURE, GARDENING, ETC. Draining and Embanking: A Practical Treatise. By Prof. John Scott. With 68 Illustrations "1 /Q Irrigation and ISTater Supply: A Practical Treatise on Water Meadows, Sewage Irrigation, Warping, &c.; on the Construction of Wells, Ponds, Reservoirs, &c. By Prof. John Scott. With 34 Illustrations 1 /Q Farm Roads, Fences, and Gates: A Practical Treatise on the Roads, Tramways, and Waterways of the Farm; the Principles of Enclosures: and the different kinds of Fences, Gates, and Stiles. By Prof. John Scott. With 75 Illustrations . 1 /6 Farm Buildings : A Practical Treatise on the Buildings necessary for various kinds of Farms, their Arrangement and Construction, with Plans and Estimates. By Prof. John Scott. With 105 Illustrations 2/0 Barn Imjplements a.nd Machines : Treating of the Application of Power and Machines used in the Threshing- barn, Stockyard, Dairy, &c. By Prof. J. Scott. With 123 Illustrations. 2/0 Field Implements and Machines: With Principles and Details of Construction and Points of Excellence, their Management, &c. By Prof. John Scott. With 138 Illustrations 2/0 Agricultural Surveying: A Treatise on Land Surveying, Levelling, and Setting-out ; with Directions for Valuing Estates. By Prof. J. Scott. With 62 Illustrations . 1 /6 Farm Engineering. By Professor John Scott. Comprising the above Seven Volumes in One, 1,150 pages, and over 600 Illustrations. Half-bound . . . 12/0 Outlines of Farm Management. Treating of the General Work of the Farm ; Stock ; Contract Work ; Labour, &c. By R. Scott Burn ... ... 2/6 Outlines of L Animal Physics, Plandbook of. By DiONVSius Lardner, D.C.L. With 520 Illustrations. In One Vol. (732 pages), cloth boards 7/6 *^(.* Sold also in Tzvo Parts, as folloivs: — Animal Physics. By Dr. Lardner. Parti., Chapters I.— VII. 4/0 Animal Physics. By Dr. Lardner. Part II., Chapters VIII.— XVIII. 3/0 BRADBURY, AGNEW, & CO. LD,, PKINTEKS, LONDON AND TONBRIDGE. ADVERTISEMENTS. IV 1897 EDITION. The Best Legal Adviser for the Man of Business. ALWAYS KEPT UP TO DATE. Just PuUished, '^50 closely -printed pages, Crown 8vo, comprising about 4:^000 Statements of the Law . 34th EDITION. Price 6s. 8d. ; post free (Saved at Every Consultation ! !). EVERY MAN'S OWN LAWYER A Ha7idy Book of the Frificipks of Law and Equity, By a barrister. Thirty-fourth Edition (1897), Carefully Revised, including the Locomotives on Highways Act, 1896, the Truck Act, 1896, the Light Railways Act, 1896, and other New Acts of 1896. TO WHICH IS ADDED A CONCISE DICTIONARY OF LEGAL TERMS. OPINIONS OF THE PRESS. "This popular law book certainly never before presented so thorough and COMPLETE AN EPITOME OF THE LAWS OF ENGLAND." — Lloyd's NcWS. "A complete digest of the most useful facts which constitute English LAWS."— (?/^3d., e of :.c. ius- SUGA t "A . ^* J . ious prlcessesrand many practical hints~which will be of gVeat value to those in charge of them." — South American Journal. BEARINGS AND LUBRICATIONS. Crown 8vo, 220 pages, 78 illustrations. Price 3s. 6d., cloth. "Mr. Wallis-Tayler's book is one which may be studied with advantage and profit by both the machinery owner and attendant. . .... The hints the book contains may be the means of saving a good deal of time and trouble witb machinery." — The Machinery Market. London: Wm. RIDER & SON, Ltd., 14, Bartholomew Close, E.G. BOSTON COLLEGE ADVERTISEMEN' 1 1|| ||1|1 1|1|| || |||||| |||| Ml llll llll III III IIIHI HH HH HI I 3 9031 01449611 1 THE H0SL1 FOUPRY aqd ENBIKEEKINI} Co., Ltl, INCORPORATED WITH PONTIFEX & WOOD, Ltd. m' m-llis-Tayler,A.J Author Refrigerating & Ice-Makirij Title Machinery M St Pipe Adoj REF 34 BOSTON COLLEGE LIBRARY UNIVERSITY HEIGHTS CHESTNUT HILL, MASS. Books may be kept for two weeks and may be renewed for the same period, unless reserved. Two cents a day is charged for each book kept overtime. If you cannot find what you want, ask the Librarian who will be glad to help you. The borrower is responsible for books drawn on his card and for all fines accruing on the same.