Digitized by the Internet Archive in 2017 with funding from Getty Research Institute https://archive.org/details/shorttreatiseonsOOIoud TREATISE OH SEVERAL IMPROVEMENTS, RECENTLY MADE IN HOTHOUSES* ADVERTISEMENT. Models as defcribed in the Appendix to this work, are fold at Mr Dalziel’s, Chapel- Street * Bedford-Row , London ; or at Melk Dicksons and Shade’s, Edinburgh ; in whofe nurfery may be feen a hot-houfe altered agfeGably to this Treatife. A SHORT TREATISE ON SEVERAL IMPROVEMENTS, recently made in HOT-HOUSES: BY WHICH FROM FOUR-FIFTHS TO NINE-TENTHS OF THE FUEL COMMONLY USED WILL BE SAVED ; TIME, LABOUR, AND FISK, GREATLY LESSENED ; AND SEVERAL OTHER ADVANTAGES PRODUCED. AND WHICH ARE Applicable to Hot-houfes already erected, or to the Construction of New Hot-houfes. Illustrated, by Nine Large Copperplates. By J. LOUDON, MEMBER OF THE SOCIETY OF ARTS, COMMERCE, &C. STRAND, LONDON : AUTHOR OF OBSERVATIONS ON PLANTING, LANDSCAPE GARDENING, AND EMBANKING, &C. DESIGNER OF RURAL IMPROVEMENTS. — « 9CSOC® — EDINBURGH : PRINTED FOR THE AUTHOR: And SOLD BY ARCHIBALD CONSTABLE AND CO. EDINBURGH J LONGMAN, HURST, REES, AND ORME, LONDON. 00 lb05. Jobn Turnbull, Printer, Edinburgh. Til O Ed . - O . 1 ■ • jtfjmK-i- '.co .... C .Iff I » - . • - ' > . ' \ : ■ i.v 1 •••/ - >■ US. : ' -V ' . «?,:!•.. . -;o ; : .r.il'sfrv: v. iVI , / * .." • T ' ! i ; ' PREFACE. Nearly four months have elapfed fince the improvements to be treated of in the firft part of this work, were executed upon Dickfons’ and Shade’s hothoufe. During this period they have been ex- amined by a great number of refpecd- able gentlemen, who, with fcarcely a fingle exception, exprefled their warmeft appro- bation of the fcheme, and flrong convic- tions of its general utility. Among thefe gentlemen, were fome who have paid particular attention to the fubject, and they are decidedly of opinion, that the improvements here fubmitted, are calculated to be more extenlively ufeful than any thing that has yet appeared. Encouraged ( vi ) / Encouraged thus, to make them as ge- nerally underflood as poffible, the author has caufed to be made models in woody of certain parts which might perhaps uz- zle fome country artizans, who are not accuftomed to work from plans. Thefe may be examined or purchafed at the places mentioned in the advertifement. If required, models can alfo be made of the new plan for growing pines — of the improv- ed peach-houfey and of the new pity which are defcribed and recommended in this work. The attention requifite to fhew and vend thefe models, has rendered it neceffary for the author to deviate from the common mode of bookfelling. CON- CONTENTS. PART I. AN ACCOUNT AND , TREATISE OF SEVERAL ALTERATIONS MADE UPON A HOTHOUSE BELONGING TO MESS. DICKSONS AND SHADE, EDINBURGH. f la s e - Introduction, .... 9 Gen ERA1. DESCRIPTION OF THE HOTHOUSE BE- LONGING TO MESS. DICKSONS AND SHADE, PRE- VIOUSLY TO ITS BEING ALTERED. - - 12 General description of the several altera- tion^ - - - 1 7 Of the furnace and fuel-chamber. Of the furnace and fuel-chamber formerly ufed, - - - - ' " 2i Defcription of the improved furnace and fuel- chamber, - - - - - 23 Of Vlll CONTENTS. Page. Of the smoke-flue, - Of the flue before it was altered, - - 31 Of the improved flue, - 3 2 Of the air-flue, Of the intention of the alterations upon THE FURNACE AND FLUES, - " “ 39 Of the mode of using the improved fur- nace AND FLUES, ----- 54 Of managing the valves in the furnace and afh-pit doors, - - - - - 55 Of the inner roofing, Of its conftrucffion, and the mode of fitting it to the hothoufe, 65 Of the intention of the inner roofing, - 73 Of the mode of ufing the inner roofing, 80 Of the air-pump, or air-bellows, Of the different purpofes for which air is ad- mitted into hothoufes, - - - 83 Of the conftrudtion of the air-pump and bel- low's, ------ 90 Of the intention and mode of ufing the air- pump or bellows, _ - - - 94 Of tfie ventilator, Of ventilation, ----- 99 Of the conftru&ion of the ventilator, - io 7 Of the intention and mode of ufing the venti- lator, - - - - - - 1 1 1 Of CONTENTS, ix Page. Of the advantages resulting from these IMPROVEMENTS, - - - - - Il£ Of the advantage, in the cafe of Dicksons and Shade’s Hothoufe, - - ny On the advantages which will refult in general cafes, - - - - - - 123 Of the expence of making these alterations, WITH REFERENCES TO WORKMEN WHO CAN BE SENT TO EXECUTE THEM UPON HOTHOUSES TO ANY PART OF THE COUNTRY. - - - 1 2 7 PART II. ON OTHER IMPROVEMENTS WHCB MAY BE MADE IN HOTHOUSES. Of the introduction of improvements in HOTHOUSES, - Of additional improvements in the modes of HEATING HOTHOUSES, - Of HEATING HOTHOUSES BY STEAM, AND OF STEAMING IN- GENERAL, - *35 *57 Of x CONTENTS, Page. Of a new plan for growing pine apples s 165 Of an improved pit for growing young pines, RAISING CUCUMBERS, MELONS, iS ’ c . - 17S Of AN IMPROVED PEACH-HOUSE, - - l86 Op ARCHITECTURAL DECORATIONS IN HOTHOUSES, Conclusion, ------ 202 Explanaton of the plates, » 205 Postscript, ------ 244 ERRATA. Page 149, *59> J 95> 200, line 3, dele to the line 5, for from read to 4, before fame read an account of 19, after training read upon 1 7, for panes read frames. Some other errors which do not alter the fenfe, and in particular an erroneous enumeration of the chapters, the reader is intreated to pafs without cenfute. V : u ■ . I * t - > A N ACCOUNT 0 s SEVERAL ALTERATIONS, kfr. INTRODUCTION. It was the original intention of the author not to have printed any thing refpe&ing thefe improvements until he publifhed his treatife on Hothoufes , Hot walls , &c. This treatife was intended to be pretty full — to be printed in quarto, and to contain many new defigns — with an Appendix, containing numerous criticifms upon hothoufes ere&ed in different parts of this ifland. He is however induced to keep back this work at prefent, B partly ( 1 ° ) partly from want of time to fuperintend the prefs, partly from a defire to try the fuc- cefs of feveral other new and equally impor- tant fchemes before he fubmitted them to the public, and partly alfo, that he might enlarge the number of criticifms, by viewing and examining fome hothoufes which he has not yet had an opportunity of feeing, but which he expeds to fee in the enfuing feafon, in the courfe of an intended tour through the ifland. On the other hand, the author has been induced to write this account, from the ad- vice of feveral intelligent gentlemen who conceive highly of its utility, and at the de- lire, and for the benefit of a very confider- able number who have already begun to alter their hothoufes according to this plan ; and in fome degree alfo from a reafon, the detail of which would reded no great ho- nour upon a certain clafs of men. The thing alluded to, however, is juft what the author ( 11 ; author expeded, from the fudden introduc- tion of a plan which hrikes at the root of fome of the mod; important points of ge- neral, and even much approved pradice, in the conftrudion of hothoufes. But in con- fequence of the fuperior nature and advan- tage of his fcheme, he has nothing to fear, and rehs perfedly fatisfied, that in this libe- ral and improving age, thefe alterations will meet with general approbation, and be adopt- ed according to the degree of their real utility — and this too, not the lefs readily, becaufe, at firft, they may be decried, or oppofed, as all the mod: ufeful difcoveries in other branches of fcience or of art have been, by fome interefted, ignorant, and little minded men. B 2 general ( 12 ) GENERAL DESCRIPTION OF THE HOTHOUSE, BE- LONGING TO MESS. DICKSONS AND SHADE, UPON WHICH THE IMPROVEMENTS WERE MADE. The hothoufe upon which thefe alterations were made, was built about three years ago, from apian given by the author, according to the mod: approved and economical mode of building hothoufes at that time. It anfwer- ed the intention very well ; and indeed, from fome particular circumftances to be men- tioned, fully better than mod: hothoufes ; for being of a fmall dze, and the ends being built of folid wall, which is always warmer than glafs, it was heated by the dues with more than common eafe, and this heat, from the fame circumftances, was retained for a more than ordinary length of time. But ( 13 ) But in order to give the reader more clear ideas, it may be neceflary to obferve in the wayofdefcription, that this houfe is twenty- three feet long, fourteen feet broad, ten feet high in the back wall, four and a half feet high in front, (infide meafure ;) that the two ends, back and front, are built of mafon work, and three feet of the hope at the top of the houfe is covered with deal — the reft of the flope with eleven fafhes, glazed with what is called fragment glafs, being old ones formerly ufed for another purpofe, and fit* ted up here for the fake of economy. The furnace, or fire place, was placed at the north-eaft corner, in a mafs of brick- work, four feet broad, four feet deep, and which proje&ed three feet from the wail in the ufual manner. The flue in the infide of the houfe was led firft along the front, and then round at the bottom of the back wall, and entered a fhaft, or chimney, immediately above the furnace. The ( *4 ) The houfe was ufed for forcing flowers, &c. ; and hence the flue furrounded a bark or tan pit, which reached within four feet of the glafs behind, and eighteen inches of it before. From this defcription the reader will be aware, that this hothoufe is very fmall, and confequently unfavourable for {hewing the effedt of the improvements which have been made, on the three following ac- counts : 1. It was fo eafily heated by the com- mon mode. 2. Having no glafs in front, nor in the ends, but only in part of the roof, the heat raifed was longer retained, than happens in the cafe of any fmall hothoufe, having glafs on the ends and front, as well as the roof. 3. A fmall hothoufe, in all cafes, con- fumes ( i5 ) fumes a greater proportion of fuel than a large one, as in dwelling-houfes is well known to be the cafe with final], in com- parifon with large rooms. Under thefe difadvantages, it may appear furprifing to fome, that the author fixed upon this houfe as a fubjefl of improve- ment. It is true, indeed, he could have made the alterations upon many gentlemen’s hotlioufes, with a much greater effefl ; but he judged it better for the public to execute them in fome nurfery, (a nurfery being a kind of public place,) where they might be feen and examined by gentlemen with great - er freedom. And though this hothoufe belonging to MefT. Dickfons and Shade, is far from being the belt in the nurferies about Edinburgh, he preferred it, becaufe (from fome knowledge of moil of the nurfe- ries and nurferymen in Scotland, and that of a more clofe and intimate kind than generally C 16 ) nerally can be the cafe with landed gentle- men,) he is induced to give this company the preference on moft occafions ; and he can, without the leaf! helitation, recommend them to the gentlemen of this country. GENERAL ( 17 ) GENERAL DESCRIPTION OF THE SEVERAL ALTERATIONS. In the following pages they fhall be defcri- bed and treated of, in an order, correfpon- ding in fome degree, with their importance: viz. 1. The furnace and fuel-chamber in which the coal or other fuel is confumed. 2. The Jmoke-flue t which condu&s the G fmoke ( >8 ) l'moke round the houfe, to the {haft or chimney by which it efcapes. 3. The air -flue, which collects heated air around and near the furnace, and conveys it to the oppofite end of the houfe. 4. The inner -roofing, being a coarfe flan- nel curtain let down under the glafs, dur- ing night, to prevent the air of the houfe from coming in contact with the glafs. 5. The air-pump or bellows, intended for pineries and doves, to force or draw in frefh air of moderate temperature, during the winter months. This air can generally be obtained from the back f beds . 6. The ventilator , intended either to put the air of the houfe in motiond uring the day; or at ( 1 9 ) at pjeafure ; and thus to imitate the natural breeze. After thus defcribing and treating of thefe alterations, and the intentions, and ufe of each of them feparately, fome obfervations will be added under the following heads : viz. 1 . On the advantages refulting from thefe alterations. 2. On the expence of making them, with fome hints to gentlemen intending to alter hothoufes according to this plan ; and re- ferences to workmen in Edinburgh who underhand the practical parts of thefe im- provements. 3. On other improvements which may be executed on hothoufes. ( 20 ) Among other things in this chapter, will be fuggefted new plans for pine-hoves, peach-houles, and pits, which the author conceives, will, be conliderable improve- ments. CHAP. ( 21 ) CHAP I. I OF THE FURNACE AND F U E L-C H A M B E R. SECTION I. Of the Furnace and Fuel-chamber formerly ufed. Before the alterations were made, the furnace, as already mentioned, and as is ge- nerally done, was placed in a large mafs of brick work attached to the houfe. Its chamber or fpace for containing the fuel, w T as ( 22 ) was two feet long, eighteen inches wide, and eighteen inches high. The furnace-door, a Angle plate of call iron, ten inches fquare. The floor, or bottom of the fuel-chamber, had five iron bars which formed a grate, fourteen inches long, and ten inches wide; having a dead or folid fpace of four inches on the two fides, and ten inches behind* or in the farther end of the chamber. Thefe dead fpaces were intended for the purpofe of making the fire burn flowly, and lafi: long, agreeably to the principle recom- mended and pra&ifed by Mr Nicol *. The afh-pit was eighteen inches long, and ten inches wide, and without any door. Sect. * See The Forcing Gardener, 3d Edit. pub. 1802. I ( 2 3 ) SECTION II. Defcription of the improved Furnace, and Fuel-chamber* A furnace was made fo far fimilar to Count Rumford’s that it had double doors, but different in all other refpe&s : for, 1. The outer and inner doors were al- moft exa&ly of the fame fize, and con- fequently, the fides were nearly at right angles with the front, which is a very great advantage in fixing it in mafon work. 2. It contained one opening in each of its fides, for the purpofe of communicating with the air flue to be afterwards defcribed, 3- rt ( ( 2 + ) 3. It has a valve in the centre of the outer door: and, 4. It has four nobs or projections at the corners, which are for the purpofe of fixing it in the building. Thefe and the other parts will be belt underftood from plate I. fig. 1. The fize of the furnace door ufed is J, even and a half inches , which is fufficiently large for this houfe, thougn too fmall for general and convenient ufe. A door ten inches fquare, with a valve in it, was alfo got for the afh-pit. See plate I. fig. 2. The mafs of brick work, containing the old furnace and afh-pit, being taken down, the bricks and the five metal bars were referved to be ufed in building up the new furnace. It ( 25 ) It is worthy of remark here, that of all the old materials, the furnace door alone was not re-ufed ; and this, not becaufe it would not anfwer, but merely to try the effeds of one with a valve. But a furnace door with a valve in it, is by no means effentially ne- ceffary, and in general gentlemen who make alterations according to this plan, may very fafely ufe the old furnace door as a door to the new afh-pit, in place of fending for a new one with a valve. A large hole being made in the lower part of the wall of the houfe, the new afh-pit and furnace were built under it, projed- ing fo far into the houfe, as that the outer furnace door, and the door of the afh-pit, were even, or “ flufli” as workmen term it, with the outer face of the wall. The afh-pit was made fourteen inches long, and ten inches wide : and, The old bars were laid above it, form- D ing C 26 ) ing the grate, and chamber for the fuel. The furnace was then properly placed, and the grate built round, (except at the neck of the flue, which was of courfe kept open,) with bricks laid flat, that is brick on bed,” as fhewn plate I. fig. 3. This building was carried up twelve inches, and then arched over in the ufual manner. Over this arch was made another of the fame thicknefs, preferving a vacuity betwixt them of three inches, which va- cuity joins with each fide of the furnace door, in order to communicate with the holes or openings formerly mentioned, and as (hewn in plate I, by figures 3, 4, and 5, which are tranfverfe and vertical fe&ions. In examining thefe two feftions, fome things will be feen which deferve atten- tion. In ( 2 ? ) In figure 3, the contraction of the air vacuity at g and b 1 is made for the purpofe of confining and ftagnating the air, in order that it may be thoroughly heated before it pafles along the air flue into the houfe. The Valve in the furnace door, and alfo the holes in each fide, which communicate im- mediately with the vacuity, are alfo made fmall, in order that alargebody of coolairmay never be admitted at once. For it is a facft, that were the vacuity, valves, and air flue, every where of equal width, the air would pafs rapidly through into the houfe fcarcely heated at all ; unlefs, perhaps, when the fire was very ftrong and the furnace door red. hot. It may be obferved here, that the arch over the air vacuity, can be fupported upon the under one, by making the ends of two or three of the bricks project down and reft upon ( 2S ) upon the top of it, as fhewn in figure 4; or two or three pieces of brick or flone laid carefully upon the under arch, will ferve the fame purpofe. But there is no abfolute necefftty for fuch fupports ; the intention is merely to guard againfl the linking of the upper arch. It is needlefs to add what every mafon or bricklayer knows, that thefe arches can eafily be “ thrown” or built, by filling the fuel- chamber with earth, or by laying in bricks or any fuch loofe materials, which can be taken out as foon as the mortar hardens fo as to leave the arch entire. The arch above the vacuity can eafily be made in the fame manner. In figure 5, the large chambers i and z, and the contraction at the beginning of the ( 2 9 ) the air flue k y are for the purpofe above mentioned. There is no neceffity for thefe chambers being in every cafe fo large as fhewn in the plate; although a proportion fomewhat fimilar, will generally be found preferable. In figure 5 alfo, a fmall recefs will be ob- ferved betwixt the grate and the flue, for the purpofe of preferving a portion of the fuel which fhall bum flowly ; and thus it is pre- fumed live-coals may be had from that re- cefs for twenty-four hours after the fire is kindled. Some may think that a plain dead fpace larger than this recefs would ferve equally well ; but this on examination will appear an ill founded idea ; for if we obferve the dotted line, m n in the plate, it will appear that it could not preferve the coals alive for a fufficient length of time, unlefs the throat of the flue were made much more upright ; which on the other hand would preferve ( 3° ) preferve too much fuel, and very much pre- vent the heat either from palling through it into the air vacuity, or onwards into the fmoke flue. This improvement I did not think of when the furnace at Dickfons and Shade’s hothoufe was built ; but I now fee from the fires then being fometimes totally extinguifh- ed in the mornings, that it will be a benefi* cial addition to the plan. CHAP. ( 31 ) CHAP. II. OF THE SMOKE FLUE. SECTION I. Of the Flue before it was altered . As already mentioned in the general de- fcription, the dire&ion of this flue was round the houfe. It was built, very properly, upon fupports *, and totally detached from the * Mr Nicol always builds his flues upon fupports, for which he deferves credit : the pra&ice is totally un- known in feveral parts of England, and not fufficiently attended to by fome in this country. ( 32 ) the front wall, or any other building, which is alfo an important point to attend to. But though there was ample room to make the flue of confiderable depth, this was negle&ed, which is a very great, but univerfal error. Still, however, the depth of three bricks placed on edge was allowed, that is about fifteen inches, which depth is not always given, for we find even fome planners and others, who though they ge- nerally build their flues of this depth, yet contend that the breadth of two bricks is perfectly fufEcient. SECTION II. Of the improved Flue. This old flue was taken down, and built up five bricks in breadth , — as great a depth as in this cafe, could be accomplifhed. “ Briggs,” I ( 33 ) “ Briggs,” or perpendicular partitions, reaching from the covers till within a brick and a haif of the bottom, were formed by placing bricks acrofs, and joining the two (ides of the flues. The firft of thefe, was placed twenty feet from the furnace, and the reft about ten or twelve feet diftaht from one another, as ftiewn in figure i . plate II. Thefe “ briggs” divide the flue into chambers, or compartments, each of which will naturally be completely filled with fmoke and heat, before any can occupy the next; and, hence the whole flue muft be completely filled, before any can efcape at the chimney top. The flue is made of five bricks breadth in depth, at both ends, and along the front of the houfe, and in this fpace it had three briggs, or partitions, viz. two in the front, and one E in i 34 ) in that end farthefl from the fire. For to have made one in the end where the fire enters* would have had a tendency to make that part of the houfe too warm. The back flue was made of the ordinary depth, with only one projedtion, placed at its termination, immediately before the fmoke afcended into the fhaft or chimney. Had the houfe been large, the whole length of the flue fhould have been made as deep as poffible; and a confiderable depth may gene- rally be obtained, particularly in pine or plant floves, or even in vineries and peach houfes, when thefe are trained under thelloping glafs. But in alrnoft every cafe that may occur, when vines are trained upon the back wall, it will be improper to make the flues deeper than three bricks ; yet even here, the « briggs” fhould be made to reach the fame C 35 ) V fame depth as before, that is, within a brick and a half of the bottom of the flue. Or, the flues in fuch houfes may be made of double width, or as wide as can be con- veniently accomplifhed, and the “ briggs” may be carried up from the bottom, leaving a fmall hole in the foundation of each brigg, of twelve inches long, by four inches wide, or larger, according to the fize of the furnace. Through this hole the fmoke will pafs from chamber to chamber. The air flue, built upon the top of fuch flues as this, need only be its full breadth from the furnace to the firft compartment ; afterwards it may be carried on in a narrow flue, or in an earthen or pi ate- iron pipe, to the end of the houfe. But of the air flue in next fedion. In the middle of the {haft is placed a damper, the intention and mode of uflng which fhall be prefently explained. E 2 CHAP, 1 \ ' ‘ x ( 36 ) CHAP, III, OF THE AIR-FLUE. The vacuity around the fire-place is conti- nued on each fide, and over the top, as well as under the bottom of the fmoke flue, for about four feet in length, as fhewn in plate I. by figures 4 and 6. The two fide and bottom vacuities, are continued no farther, but there unite with the fpace at top, which top fpace is conti- nued on, as an air flue to the oppofite end of the houfe. And there it terminates, allowing the heated air to efcape, as fhewn plate II. fig. 1. The ( 37 ) The top of the fmoke flue ferves for the bottom of the air flue, which is one 4 - 4 brick on edge” in depth, and covered with tyle or pavement fimilar to the fmoke flue. A ftone or brick neatly fitted to the end of the air flue, ferves to clofe it up when requifite. Both the air and fmoke flue, were plafler^ ed in the outfide for the fake of appearance, as the bricks were very coarfe and unfight- ly : but in the infide of the flue, this was, and ought always to be avoided if poflible, as plafler is a non- conductor of heat. But had the bricks been equally neat and beautiful with thofe made in the neighbour- hood of London, no plafler work would have been neceffary : the joints would have been neatly puttied of the fame colour as the brick, and at molt a coat of paint of a brown or cream colour, would have been given . ( 38 ) given. For it is prefumed they have no good tafle who prefer to this flyle, walls and flues covered with white plafter, the raw glare of which when oppofed and inter- fperfed among the delicate green of vegi- tation, has a harfli and unharmonious effect. Having thus endeavoured to defcribe the alterations made upon the furnace and flue, which it is hoped by the afliflance of the plates, will be underftood by the reader, and by intelligent workmen, fome obferva- tions fhall next be added refpe&ing the in- tention of thefe alterations. CHAR ( 39 ) CHAP. TV. OF THE INTENTION OF THE ALTERATIONS UPON THE FURNACE AND FLUES. In the JirJi place, the particular intention of this furnace is to confume or ignite the fuel as quickly as poffible. For this pur- pofe no dead fpace is left on each fide, as in Mr Nicol’s improved furnaces; but on the contrary, the grate occupies the whole breadth of the chamber, in order that no part of the fuel may remain unkindled. At the C 40 ) the fame time a recefs under the throat of the flue is made to preferve fome live-fuel in order to rekindle the fire. Secondly , The depth of the flue is intended to produce a greater mafs of brick work, to be heated at the leafl: expence, which heated mafs will continue longer to give out heat to the hoiife, and thus by making one fire ferve in place of a number, will confe- quently fave much time, and produce a more fteady heat ; an advantage independent of the faving of fuel. In fome cafes breadth may be ufed in place of depth, and then the briggs may be literally divifions, or partitions, each with a hole at bottom, fix or eight inches fquare : or of the dirtienfions given laft chapter. Thirdly, The briggs are intended to heat this mafs more uniformly and effectually, by ftagnating the fmoke. And as the hotteft of that ( 4i > that contained in each compartment, will al- ways rife to the top, fo the coldeft, will in the fame way be forced out under the partitions. What was the coldeft fmoke of the firft com- partment, will be the hotteft of the next ; of courfe it will afcend and prefs out that which is ftill colder, and thus will the fmoke pafs through the feveral compartments un- til it has given out the greater part of the heat which it contains, and at laft, when quite cold, it is forced up the fhaft, or chimney. Befides this very great advantage, thefe briggs, or partitions, are alfo found to in- creafe the draught of the fire. Fourthly , The double furnace-door, and the vacuity around the furnace, are intended to colletft that heat, which in other furnaces is totally loft in the adjoining mafs of mafon work. F Fifthly, ( 42 ) Fifthly , This vacuity is alfo continued around the flue for the diftance of fome feet from the furnace, in order to collect a quantity of heat, which would otherwife, as is generally the cafe, make that end of the houfe confiderably warmer than the other, or oppoflte end. Sixthly , The vacuity, or air flue, conti- nued from thence along the top of the fmoke flue only, is intended to convey the heated air collected as above, to the other end of the houfe: Which part of the houfe being fartheft from the fire, is, in general, too cold ; but by this means it is rendered equally warm with the other. Some may think that when two fires are ufed, one being placed at each end of the houfe, the temperature would be regu- lar, and the heated air would be allow- ed to efcape from the furnace immediately into ( 43 ) into the houfe. But without hating any of the many and great arguments againfl this, it is fufficient to obferve, that according to this new plan, in no cafe whatever, will two fires be neceflary. It will always be found more economical to augment the fize of the furnace, in proportion to that of the houfe to be heated. F 2 CHAP. ( 44 ) CHAP. IV. - OF THE MODE OF USING THIS FURNACE AND THE FLUES. Suppose the fire lighted, and the fuel thrown in, the furnace doors are to be fhut clofe, and alfo the valve in the outer door turned round, fo as not to admit any air. But the afh-pit door, and the damper within the houfe, mu ft be thrown open. As ( 45 ) As foon as the grofler part of the fmoke is diflipated, and the general mafs of fuel becomes nearly red hot, or almoft covered with flames, which, in an ordinary furnace, will generally happen in twenty minutes, or half an hour, after the fire is kindled, — clofe the afh-pit door, open the valve in the outer furnace-door, and fhut the damper. Thefe operations produce the three fol- lowing effects, viz. 1. The fire is preferved ftationary; that is, the fuel is no longer confumed with the fame degree of rapidity. 2. The whole heat generated, is ftagnated in the flue. 3. The cool air entering by the valve, is rarified, partly on the furnace door, but principally in the vacuity around the fur- nace, ( 46 ) nace, and thus is prefled forward into the houfe. The fire being preferved in a good de- gree ftationary, the great heat which is con- tained in the fuel now red hot, does not en- ter the flue to make a violent irregular heat in the houfe, but it heats the air in the va- cuity which furrounds it. This heated air being allowed to pafs into the houfe, is a more fpeedy, effec- tual, and uniform way of heating it; be- caufe it mixes at once with the air al- ready in the houfe, whereas by the com- mon mode, every particle of the air con- tained in the fame, muft come in contact with the flue before the houfe is properly heated. Now, to allow time fufficient for this procefs, the fire muft be kept burning for a very confiderable time, and no fooner is the degree of heat requifite obtained, than the flue, {till as hot as before, and now aid- ed ( 47 ) ed by the fun upon the glafs, raifes the temperature to a height greatly beyond that which was required. This is particularly the cafe, as every gardener knows, during the mornings of the winter and fpring months. The apprentice lad, or in fome cafes the mailer himfelf, comes to the hothoufe, perhaps at feven o’clock in a clear frofly morning, in the end of January; he finds the thermometer Handing ten or fifteen degrees below the proper or required temperature. To remedy this, he with all fpeed puts on as large a fire as pollible — perhaps it is well kindled by eight o’clock, but no heat is yet added to the houfe ; on the contrary, much heat has been efcaping from it, and the thermometer is now fix or eight degrees lower than before. About half pafl nine o’clock, and not always fo foon, the thermometer indicates the proper degree of heat. Though the air be frofly, and the morningflillcold, yet now the fun-beams dart upon ( 48 ) upon the glafs with much vigour ; and about twenty minutes, or half an hour paft ten, the thermometer is ten or twenty degrees higher than the proper medium, and con- tinues to rife with rapidity. At eleven the houfe is at an alarming degree of heat, and no alternative remains for the lad, but to let down the fafties, in order to admit frefti air; for though he had juft before opened the furnace doors, its effects are comparatively much dower. Now it is evident, that no fooner are the falhes thrown down, however little a fpace, than the gravity of the clear “frofty”airof the atmofphere, nifties into the houfe, andforcing out the light heated air, which at any rate has a continual tendency to afcend, occu- pies the houfe in a few feconds. Thus the plants are brought in one moment from the climate of the torrid zone, to that of the polar regions. In ( 49 ) In the mean time, the furnace door being thrown open, the cool air entering and rufh- ing through the flue, makes it as cold in an hour as it was before the fire was put on. And again, perhaps ten or fifteen minutes after the fafhes were opened, the lad per- ceives, (for he is under the neceflity of being always upon the watch,) that the houfe is too cold— inftantly he draws up the fafhes, ftirs up the fire, and fhuts the furnace < door. What is the confequence ? The joint effects of the fun, now more powerful than before, and the fire, which not being fully exhaufted, is eafily rekindled, produce the fame extreme as formerly! The fame remedy is applied, which again is attended with the fame baneful confequences, to ve- getation. This rotation of extremes goes on almoft without interruption, in the pineries and ftoves, every funfhine day, during three quarters of the year, and in vineries peach- G houfes, ( 5 ° ) houfes, &c. during the beginning of the forcing feafon *. The bad confequences which refult from this practice, it may fafely be faid, are in- calculable. The above will no doubt be agreed to by every one lo far ; but perhaps when it is faid, the one extreme is as the torrid, the other as the frigid zone, it will be denied, for it will be faid, the thermometer in the hothoufe, never is feen lo low, as even in the open air. But this, like many other common ideas, arifes from want of due * I had the moft complete opportunity of knowing this, about eight years ago, when I was afliftant to the late Mr Mawer, Planner and Nurseryman, Dalry, near Edinburgh. I faw it happen every day in his own hothoufes, which, as is well known, were at that time, the moft extenfive, and beft conftru&ed in Scotland. Several particulars refpetfting thefe hothoufes, and parti- cularly about the extenfive fteam operations then carried on, will appear in the treatife on Hothoufes. ( 5i ) due confideration of the fubjecl, and from ignorance of the do&rine of heat. For, it is evident that the extremes of heat in the houfe, being fo much more ra- pid than the motion of the mercury in the thermometer; the higheft or lowefl degree of thefe extremes, can never be indicated, owing to the impulfe of the fucceeding ex- treme, counteracting the true indication of the former one. For it is well known, that a thermometer in air takes feveral minutes to indicate the true temperature of the me- dium in which it is placed. Hence, to be fhort, if the real tempera- ture of the extremes in the houfe are as the line A , the temperature indicated by the thermometer will be fomewhat correfpond- ing to the line B, two ( 52 ) two lines very different when obierved fe- parately. It may be fafely faid, that in three mi- nutes after the fafhes are let down, the houfe is of the fame temperature as the at- mofphere: At that temperature, it remains until the thermometer about to indicate it, is checked by heat, fuddenly generated by the fun and the flue. From this fhort ftatement of what really happens, the fickly appearance, and debili- tated habits of hothoufe plants, compared with the frefh robufl luxuriance of thofe reared in the open air, will not appear fur- prifing ; and the frequent failure of crops of fruit will be perfectly accounted for. But the evils recounted can never happen with furnaces and flues, built according to the plan recommended; becaufe, In the firjl place, The temperature of the houfe C 53 ) houfe when heated by fire alone, will be at all times fo uniform as to render great exer- tions to counteract any extreme totally un- neceflary ; and, In the Jecond place, Suppofmg the houfe at the required temperature, and a brifk fire in the furnace at the time, (a cafe by the bye that could feldom or never happen ;) if the valve in the outer furnace door is clofed, and alfo the aperture at the extre- mity of the air-flue, the heated air will be completely flagnated, and the greater part of the heat will be confined in the furnace and the air- flue, to be let into the houfe when wanted. It is true, indeed, that a certain quantity of heat will efcape through the mafon work, notwithftanding thcfe ope- rations; but this will be fmall comparative- ly with what happens in the cafe of com- mon flues, for this particular reafon, that air (in this cafe, the air of the air-flue) is the / the very worft condu&or of heat known : But fuppofing that any thing like an over- heat fhould occur, it can be completely over-balanced at once ; and without chil- ling the plants in the leaft degree, by the air-pump, as will be fhewn in the proper ( 55 ) . . ' J CHAP. V. OF MANAGING THE VALVES IN THE FUR- NACE AND ASH-PIT DOORS. Two or three diredions on this fubjed are thrown into diftind heads for the fake of gardeners, who, it is to be obferved, may be apt to go confiderably wrong, until they have a juft idea of the effeds of the valves ; and ( S6 ) and particularly of the one in the outer furnace door. 1 . If the houfe is filled with heat to the proper degree, the fire extinguifhed, and the flue and furnace quite cold, no evil can arife from having the valves in the afh-pit door, or even the door itfelf open : And the fame may be faid refpefting the damper. 2. If the houfe and flues, &c, be in the fame ftate as above, no great evil can arife from having the furnace door, or its valve, open; becaufe fuch is the ftationary nature of air, (fo to fpeak,) particularly in fuch an intricate, lengthened, and horizontal confine- ment as this, that it will not enter the houfe through the vacuities, and the air-flue. Thefe two cafes apply principally to the fummer months, and are comparatively of little importance. But, 3 - ^ \ ( 57 ) If a ftrong fire is put on in the after- noon or evening, and the afh-pit valve, or the afh-pit door itfelf, be left open during the night, the fire will be foon exhaufled, and the houfe cooled. Care, therefore, muft be taken to keep it fhut at all times through the night, and always through the day, when the fire is in a proper ftate for fhut- ting in the damper. It is proper to notice here, however, that the briggs, for fimilar reafons to thofe given in direction 2d, will prevent the flue from being half fo much cooled, as is the cafe in common furnaces and flues. The valve in the afh-pit door, it may be obferved, is of no eflential ufe ; for the door itfelf can be opened, more or lefs, accord- ing to the frefh air wanted for the fire. This valve is principally neceffary in large houfes, when a fmall quantity of air may be admitted to enter by the furnace, H forcing ( 53 ) forcing an equal quantity of fmoke off, by a fmall opening at the damper, and at the chimney top. This opening is left by not fhutting the damper quite clofe. But thefe operations are unnecelfary in a fmall houfe, and can feldom indeed be done without confiderable lofs of heat. 4. If a ftrong fire is put on in the after- noon, and when the alh-pit and damper are clofed, the valve in the outer furnace door is left fully open ; the houfe will be rendered too hot at the beginning of the night, and too cool before morning; for the air will continue to rufh in until it has nearly cooled the fire place. But it deferves to be remaked as above, in dire&ion 2d, That fuch is the flationary nature of air, and particularly in fuch an intricate lengthened and horizontal confinement as this vacuity, that ( 59 ) that though the valve was left fully open, the houfe would not be greatly cooled *. Obferve, that it is more fafe to* turn it round, fo as to leave an opening about one fourth of the full fize. This will keep a fmall, but uniform current of air entering the houfe during the whole night. 5. In the morning when the fire then put on, is fo far confumed or kindled, as to be in a ftate fit for doling the afh-pit door and the damper, if the temperature of the houfe is much too low, open the valve fully ; but if it is not required to raife the tempe- rature much, then open it one half only. Shut it entirely if the houfe is fufficiently H 2 hot, * Nothing like what fome have experienced, who have placed large plate iron pipes acrofs the chamber, with one end in the houfe, and the other in the open air. See Evelyn’s Account of his Confervatory, in the 10th edition of Kalendarium Hortenfe. S ( 6o ) hot, or open it, and while heated air is ad- mitted, pump in cool air to lower the tem- perature of the houfe. Thefe directions, it is to be feared, will give fome an idea that this furnace and air- flue, are of too intricate a nature for gene- ral practice; but, the contrary may be feen at Dickfons and Shade’s nurfery. And the whole alterations will, wherever they are eventually executed, be found to give much lefs trouble than the common furnace and flues. 6. This may be a proper place to ob- ferve, that, from the experience of the above hothoufe, in January and February laft, in fevere weather, one fire put on in the af- ternoon, twenty or thirty minutes before the men gave over working — was ready for fhutting the afli-pit and damper, and turning the valve one fourth open at that time, * ( 6i ) time, and that this fire ferved until next morning. That a fmall fire put on in the morning, and managed as above directed, (fee direction 5.) lafted till the afternoon. That in mild weather, one fire put on in the afternoon, lafted for twenty-four hours. In that furnace in Dickfons & Shade’s hothoufe, no recefs, as advifed, is made for preferving live-coals to rekindle with, yet when the fire is not too much exhaufted, by throwing in a fhovel full of coals or allies, before the damper is Ihut in, it can be lighted perfedly from the red allies next morning. From the very fmall fize of this furnace, and from the gardener allowing the fuel to be too much confumed before he Ihut in the damper, it was, when firft tried, gene- rally extinguilhed in the morning ; but, by taking care to Ihut in the damper as foon as the grofier fmoke was expelled, it has re- mained in a ftate proper for being re- kindled ( 62 ) kindled for twenty hours, and had it been of fuch a fize as is reprefented in the plate, I fhould fcarcely think the recefs necelfary. Every gardener knows, that in kindling the fire from the allies, the live coals mult be drawn over the grate to the front of the furnace, and the frelh fuel thrown in im- mediately behind them. It may be remarked here, that when a few coals are thrown into the furnace in the evening, immediately before {hutting in the damper, the fire is lighted with un- common eafe next morning. The mere opening of the afh-pit door and the damper, has frequently made it blaze without being ftirred up. This is owing to the prefence of the betuminous part of the coal, which could not be carried off in the form of finoke, becaufe, by fhuttmg m the dampei, l$c. no frelh air was allowed to come in contaft with it. CHAP. ( 63 ) CHAP. VI. OF THE INNER ROOFING. SECTION I. Of its Con/IruBiotiy and the Mode of Fitting it to the Houfe. The inner roofing is fimply a collection of curtains of coarfe woollen cloth, which are made fo as to flide down upon wires, fix or eight inches within the glafs. Thefe ( 6 4 ) Thefe curtains can be drawn up, and le£ down at pleafure, by means of cords and pullies. Each curtain may be made ten or fifteen feet broad, and of fuch a length as will reach from the top down the floDe and upright glafs, to the front wall. Along the one end of each curtain is at- tached a rod of wood about an inch or two inches fquare, and the other end is fixed to the top of the houfe : or, in l'ome cafes, to the bottom of the upright glafs. This is done — either by fimply nailing on the edge of the curtain; or by fixing it previoufly upon a piece of wood, which wood can be fixed up, and may be taken down, along with the curtain ’whenever the inner roof- ing becomes unneceflary. Whatever be the breadth of the curtains, each has along one edge a row of hooks, about two feet afunder, and at the other edge,aftripeof cloth, fix or eight inches broad, is ( 6 S ) is left unfixed at top, and without being- attached to the rod at bottom : which is by way of overlay, to be ufed after the curtains are let down. In the edge of this overlay are fixed rings which are intended, in con- junction with the hooks, to fix and join the curtains together after they are dropped. The overlay, rings, and hooks, &c. will be feen in fig. i. plate III. where a a is the overlay, b b the rings, c c the hooks, d d the cord, and e e the rGd fixed to the end of the curtain. There are too ways of ufing the cords and pullies, which fhall be defcribed. In the firjt way, a row of rings are fixed about eighteen inches afunder, in a line down the centre of the curtain. Through thefe rings a cord is paffed and fixed to the rod of wood at bottom, as is {hewn in plate III. fig. i. The other end of the cord is paffed through a fmall hole in the upper end of the curtain, and (after the I curtain ( 66 ) curtain is fixed) from thence over a pulley to a pin or hook, as fhewn in fig. 2. plate III. During the day, when this curtain is “ tucked” up, it aifumes the form exhibited by the dotted lines in the fame figure, or as more fully fhewn in fig. 6 . plate II. Thus by having the appearance of a cornice, it will be a great ornament to the houfe. When the curtain is put up according to this plan, which is the cheapefl, and will anfwer in mo ft cafes, the trellis, if there is any, muft be kept at leaf! one foot under it, or about eighteen inches from the glafs. This is recommended in order that the leaves of the trees trained on the trellis, may fuller no injury from the folds of the curtain when it is drawing up. Th q fecond mode is exactly upon the fame principle with the practice followed by up- holfterers in hanging window-blinds. The curtain, in this cafe, is rolled upon a fmall ( 6 7 ) fmall round piece of wood, on one end of which is fixed a pulley, and dire&ly under this pulley, upon the back wall, is fixed a rack pulley. A cord is made tight over both the pullies, and by moving this cord upwards or downwards, the curtain is either let down or rolled up. See plate IV. fig. 2 . When either of thefe curtains is placed at the top of the houfe, it will generally roll down upon the wires, (one of which is fixed under each rafter,) with its own weight. But, If either be placed at the bottom of the front glafs, or if the houfe is fo flat that the weight of the curtain will not caufe it to run down, then a cord mull be attached to the centre of the rod of each curtain, and that cord paffed over a pulley, placed either at the top of the houfe, or upon the top of the upright trellis or wire, as at a, in %• 3- P late IV. according as it may hap- I 2 pen, ( 68 ) pen, that the curtain is to be drawn down, from the top, or drawn up from the bot- tom. In general, however, when the curtains are fixed at top, and do not Aide down freely, this operation may be fufficiently accelerated by a fmall rod, fix or eight feet long, with a hook at one end. And, This rod will ferve at the fame time to hook on the overlays of the curtains. For the glafs ends of houfes, a curtain fiiould be made exadlly in the fame form as the end. It may be contrived, either to be drawn up from the bottom, or to roll out- wards from a pole placed upright in the angle next the back wall If of this lafi: form, it fhould have fmall rods run through it in a perpendicular direction, to preferve it exact- ly the fize of the end. Thefe rods will prove uo detriment in rolling the curtain round the pole. In ( *59 ) In this end curtain a flit mull be made immediately oppolite the door, that the operator after he has let down and. fatt- ened all the curtains, may be allowed to pafs out of the houfe. The roof curtains, may either be fixed to the end curtains, by rings and hooks, or when the ends of the houfe are of mafon work no end curtain will be neceflary. The roofing can then be fattened to it, either by common tenter hooks, or by a narrow flip of cloth nailed to the wall by way of overlay. It is almoft needlefs to add, that when two adjoining houfes are feparated only by a glafs divifion, unlefs the one houfe be a ttove, and the other a greenhoufe, or fuch like, an end curtain will not be requifite. In the cafe of a circular houfe, or one containing l ( 7 ° ) containing a number of fides, the curtain muft be fixed at bottom, and fhould be made exactly in the fhape of three or four fafhes. For example, in the cafe of a houfe circular at bafe, and terminating in a point at top, the curtain may cover four fafhes, and may be fomething of the fhape of fig. 3. plate III. y the narrow end of each cur- tain, can eafily be drawn up to the top by a cord, and one or two pullies. In. fuch a curtain as this, fmall jointed rods of wood may be introduced acrofs it, as fhewn in the figure, which will ferve ta ftretch it to the proper width. Rods of this kind, will generally be unneceflary where the curtain is equally wide at both ends. When the curtains are to come down from the top along the flope and to the bot- tom of the front glafs, the wires upon which they Hide in place of being fixed to the front, muft be fixed to an upright rod of wood C 71 ) wood or iron, upon which alfo the wire trellis muft be fixed as fhewn plate IV. %• 3 - When the curtains are fixed at the bot- tom of the upright glafs, in any houfe, a pulley muft be fixed oppofite the centre of each curtain, as at a in fig, 1. plate IV. at the top of the ftandards which fupport the wire for the cords to pafs over which are ufed to draw up the curtains. In a double roofed houfe, that is, a de- tached glafs houle Handing north and fouth, with the roof on each fide wholly of glafs, it will generally be found bell; to fix on the curtain by this laft mode. In different cafes a variety of ways will re- quire to be adopted for fitting up the inner roofing, which are not here mentioned. But it is thought that any perfon of the leaf! ingenuity, and who underftands the hints above in conne&ion with the plates, can never ( 7* ) never be at a lois how to proceed. Should the contrary happen, by fending a defcrip- tion of the cafe to the author, he will en- deavour to give fuch direffions as {hall re- move all difficulty. A number of trifling things which will occur in pradlice are forefeen by the author, but as they will not prove of any confe- quence he avoids mentioning them, left he fhould confute the practical reader. A number of curtains will doubtlefs ap- pear to fome a great inconvenience in a hothoufe, and the trouble of hooking on the overlays will be thought too great for gene- ral practice. But the contrary will be found true; for the curtains will generally be made ten or twelve feet broad, and thus four cur- tains will compofe an inner roofing for al- moft any houfe. In Dickfons’ and Shade’s hothoufe one curtain covers the whole roof- ing, which is twenty-three feet long. Every objection ( 73 ) objection of this kind therefore, appears nugatory. If any think that the danger of the cur- tain taking fire is a powerful objection, they have only to wet it with alum water before putting it up, which as any one may eafily prove by experiment, will very much hin- der it from taking fire, and wholly prevent it from burfting into flames. SECTION II. Of the intention of the Inner Roofing „ **3The ufe of this inner roofing is to prevent the warm air of the houfe from coming in contact with the glafs. An objed by this means completely effeded. The advantages which will refult from this roofing, will be underflood by every K one, ( 74 ) one, when a well-known fad is adduced : viz. That heat pafles more rapidly through glafs, than through any other material. And that on the contrary, through wool or ftagnated air more flowly than through any other body. Thefe fads are fo well known, efpecially the former, that it is needlefs to enlarge up- on them. Any perfon by handing in front of a fire or looking towards the fun, and holding before him a plate of glafs, and a piece of woollen cloth alternately, may thus eafily convince himfelf of their different ca- pacities for conducting heat. It is well known, that heated air always afcends, confequently in hothoufes, as the greateft heat is given out from the front flue, becaufe in general and in all good con- ftruded hordes, it communicates imme- diately with the fire, every particle of air, as foon as it is heated, flies up diredly to the' glals immediately above, and continues rif- ing ( 75 ) mg along the Tallies, until it arrives at the top or highelt part of the houfe ; uniefs it has before this time parted with all its heat : A circumftaace which may jultly be expected to happen, and this more efpecially, if the joints or interflices be- twixt the overlays of the panes are left open, and not puttied up, which is gene- rally negle&ed ; and often molt lludioully avoided from erroneous principles. It is no wonder that under thefe circumltances, and during the winter feafon, fo much difficul- ty Ihould arife, both in railing and keeping a houfe at a given temperature : for, inde- pendent of the interltices betwixt the panes, and the current of air, when the fire begins to decline, palling through and cooling the flue, &c. as mentioned before, the conduc- tive power of the glafs alone mult carry off an inconceivable quantity of heat. It may be obferved here, that all gentle- men who have hothoufes, ought to clofe up th-e interltices betwixt the panes without K 2 delav. ( 76 ) delay, as an immediate faving of fuel. That it is fo, mull be abundantly evident to him who will think for one moment upon the fubjed. It is therefore needlefs to take time to point out the numerous trifling, and falfe reafons, which have been given for oppo- fite ideas ; fuch as the letting off drops of con- denfed fleam — permitting foul air to efcape — preventing the frofl from breaking the glafs, Nor fhall any thing be faid refpeding the fuperiority of the other mode, but merely that it is adopted and recommen- ded by all the principal, and moft enlight- ened gardeners round London, and even by a number in Scotland ; who have uniformly found no evil confequence to refult from the pradice, (as was foundatMr Mawer’s, Dairy, where, from the fleam, it was more likely to prove unfuccefsful than in any cafe,) but on the contrary, many and great advantages in faving fuel, and keeping up the tempera- ture ( 77 ) ture of the houfe. In mofl cafes the panes fhould overlap one another about three fix- teenths of an inch, and the joints betwixt each fhould be clofed with black or red putty. It will appear evident to every one, who fhall conlider the nature of the inner roof- ing adopted, that it will, in a very complete manner, prevent the air of the houfe from being cooled upon the glafs. To prove the advantage of this, it may be thought requiiite to relate the following EXPERIMENT. Though the inner roofing in Dickfons’ and Shade’s hothoufe, is made of canvafs, in place of coarfe flannel, which lafl material muff be vaflly fuperior, yet in very cold weather in the middle of lafl month, (February) the houfe being heated in the afternoon, to the proper degree, the inner roofing was let down, and the fire allowed to go out. Next morning ( 78 ) morning the heat had only abated two or three degrees — no fire was added, but the roofing allowed to remain down all that day, (which proved to be cold and rainy,) no fire was put on that evening, and next morning at feven o’clock, the thermometer was with- in lefs than nineteen degrees of what it flood at when the roofing was let down forty hours before : and ftill it was fifteen degrees above the temperature of the atmofphere. Had the inner roofing been of woollen fluff, in place of linen, feveral: chemifls who have examined the hothoufe, and to whom I mentioned this fact, have no doubt that it would have retained the heat for one week *. Two * Coarfe linen was ufed in place of coarfe flannel, from an idea that in this trial 5 it would come cheaper ; but this is hardly the cafe, and the fuperior nature of woollen cloth, renders it decidedly preferable. ( 79 ) Two or three days after, the houfe was raifed to the fame degree of heat, about the fame hour in the afternoon, and left without putting down the inner roofing, and with- out putting on any more fires, for the fame number of hours as before. And though the weather happened to be better, than in the other experiment, the thermometer in the hothoufe, was found at the end of two nights and one day, to be only five degrees above the temperature of the open air. Thefe fads, which were witnefled by Meff. James and George Dickfon, and alfo by the gardener who had the charge of the hothoufe, Mr John Roger, a very attentive young man, will not appear furprifing to thofe, in any degree acquainted with the dodrine of heat. Sect ( 8o ) SECTION III. Of the Mode of ufing the Inner Roofing. ILittle or nothing requires to be faid un- der this head. The time of ufing it in floves and pine- ries, is during the winter and fpring months, and in vineries and peach-houfes, during the forcing feafon. During thefe periods it ought to be dropped or let down every evening, after fun-fet, and drawn up every morning, at or before lun-rife. In feafons when the curtains are unnecef- fary, they may be taken out of the houfe, and preferved dry until winter ; or if it is found inconvenient to unfix them, they can be rolled up and covered with a piece of oiled canvafs, which will preferve them from that moifiure- » ( 8i ) moifture which ought always to exift in the air of hothoufes. When the curtains of a hothoufe are all let down, though regard muft be had to have few interftices, by more or lefs carefully hooking on the overlays, yet, though l'ome of thefe may occur, no great lofs of heat will arife from them. For the whole air of the houfe being ftagnated, as well as that betwixt the inner roofing and the glafs, the quantity of heated air which will efcape through thefe interftices and come in con- tad: with the glafs, will be very fmall in- deed. It may be thought by fome, that this roofing would anfwer equally well if it was placed over the outfide of the glafs ; but this is a great miftake; for fuppoling it poflible to place it there with fufficient exadnefs, to fix it perfedly fecure againft all winds, and to glaze it againft rains, ftill the heated air of th.e houfe coming in contad with the ( 82 ) glafs, would give out fo much of the heat, as that the vacuity betwixt the cloth and the glafs in the out fide of the houfe, would be warmer than the general air in the houfe. It is not affirmed, however, that canvafs placed upon the outfide of glafs roofs, as Dr Anderfon recommends, is of no ufe : On the contrary, they have always been found of confiderable advantage. Canvafs covers for hothoufes occur in two or three places in England, and at the late Mr Mawer’s, Dairy, they were fuccefsfully ufed to pro- tect a greenhoufe. The author never heard of any hothoufes where an inner roofing fuch as he has made is in ufe, CHAP. OF THE AIR-PUMP, OR AIR-EELLOWS. SECTION I. Of the different purpofes for which Air is admitted into Hothoufes. A.ir is, or at leaft ought, to be admitted into hothoufes, for one of the three follow- ing purpofes, and frequently for all of them together. L 2 I. For ( 8 4 ) 1. For the purpofe of ventilating the houfe; that is, carrying off all the air in the houfe, and afterwards palling through it in a current, until the falhes opened are Ihut, and then the houfe is left full of new or frelh air. 2. In order to mix with the air of the houfe, that it may prove more congenial to the plants; and, 3. In order to mix with the air of the houfe, merely for the purpofe of lowering its temperature, when it is too warm. Thefe three objects being very different, it is plain, that feparate modes of accomplifh- ing them ought to be adopted. No difference however of any kind, takes place in practice; but on the contrary, whatever be the ob- je6t or purpofe, the falhes are opened or let down, without any farther thought or trou- ble. ( 85 ) ble. It is true, indeed, that in mild weather, or when the temperature of the houfe is very- high, more fafhes are let down, than when it is very cold, which is fo far good, although in faff this difference ferves little purpofe. But afide from this, the confequence of indif- criminately letting down the fafhes, what- ever may be the purpofe for which air is wanted, is this, that ventilation with the air of the atmofphere, though it fhould be in the coldeft winter day, is unavoidably produced, the houfe is fuddenly deprived of all the heated air which it contained, and not only filled with that of the atmofphere, but fanned or blown upon by a current of it, palling rapidly through among the plants. This mull neceffarily carry off much heat, chill vegetation, and bring on difeafes. To remedy this evil, it feems requifite to confider the three different purpofes for which air is admitted. The ( 86 ) The common mode of opening or letting down the fafhes, mull undoubtedly be the molt complete way of promoting ventila- tion with the air of the atmofphere ; and in mild weather, when this can be adopted, furely nothing can equal it. Refpefting this purpofe, therefore, which is the firffc mentioned, nothing further requires to be faid at prefent. The two other purpofes are accompliihed by the fame operations, and we have only to conlider, which is the beft mode of ad- mitting frefh air into a hothoufe, for the purpofe of being mixed with that which it already contains. Air is an elaflic, or compreffible body, and it is well known, that any houle or velfel filled with it, in any of its ordinary hates of expan- sion, is capable of containing double or triple the quantity of the fame temperature ; con- iequentty of containing a greater proportion hill ( 8y ) dill if the air to be forced into the houfe or vellel, is hotter than that which is con- tained in it, and a leffer proportion if the air to be forced into the houfe or veffel, is colder than that which it contains. The great ufe to be derived from a know- ledge of thefe fads in hothoufes, are evi- dently thefe: 1. The air of the houfe may be con- denfed or cooled to any temperature, not under that of the atmofphere, without al- lowing any of this heated air, now in the houfe to efcape. t 2 . The operator has it in his power to enlarge, in a double degree, this medium of refpiration (ah) for the vegetables, by forc- ing into the houfe, once a day or fo, double the quantity of air which the houfe ufually contains. ( S8 ) contains. This may be called, “ charging the houfe.” 3. It is in the power of the operator to admit a much greater quantity of frefh air, than is the cafe in ordinary hothoufes ; when it often happens, that for feveral days toge- ther, and frequently for more than a week at a time, none of the fafhes can be let down or opened. 4. That this frefh air can be admitted without chilling the plants in any degree. In proceeding to act upon thefe princi- ples, it occurred to the author, that as the atmofphere is often extremely cold in the winter feafon, there might frequently be a degree of difficulty in performing the ope- rations, and fome rifk of chilling the plants, if the air was forced into the houfe imme- diately from without, (though it is proper to ( 89 ) to notice here, that there is not one tenth part of the danger, which occurs by the common mode;) it would be an advantage, if the air to be forced into the houfe were of a moderate temperature, at leaf! two or three degrees above the freezing point. Now, as moft ftoves have, and indeed re- quire, a back fhed for covering the furnace, and for containing fuel and other materials, and as the air in thefe fheds is always tem- perate, it feems beft calculated for being forced into the houfe. From thefe obfervations, it is prefumed, the reader will fee the importance of the objedt in view, and alfo, that it is fo far a convenient and practicable plan. It re- mains only for the author to point out a machine, which may be ufed for the pur- pofe of forcing additional air into a houfe already full of this fluid. The moft econo- mical and fimple mode of doing this, ( 9 ° ) that occurs to him, is by uling an air- pump, or bellows, the form and conftruc- tion of which fhall be the fubjed of next fedion. SECTION II. Of the conJlruEtion 6f the Air-Pump and Bellows. The pump and bellows, though different in conftrudion, ferve exadly the fame pur- pofe. The pump was ufed in Dickfons’ and Shade’s hothoufe. It is fimply a fquare tube or long box of wood, open at one end and ( 9t ) and clofed at the other. (As will eafily be feen by viewing plate II. fig. 4. ; where the whole machine is reprefented with one of the fides taken off.) In this tube the board a (plate II. fig. 4.) Was ufed as a pifton or fucker. In this pifton will be feen a valve, which in prei- fing it up (by the handle) from b towards c opens and lets frefh air into the volume of the pump. In drawing down the handle, the preffure of the air in the tube or volume of the pump, clofes the valve at a in the pifton, and forces open the valve d , near the other end of the pump, through which the frefh air paffes into the houfe. This pump was placed in the top of the roof, and in the centre of the houfe, (as there happened to be no back-fhed to that hot- houfe.) A fhade or cover was fufpended over the upper end of it, to keep out the rain; and the under end, from w T hich the M 2 handle t 9 2 ) handle e proceeds, was fufpended in the houfe. This pump anlwered the purpofe of drawing in frefh air completely, but as the fafhes were very old, ill fitted to the rafters, and not glazed in the interfaces *, it was impoffible to “ charge” the houfe as men- tioned laft fe&ion, with double its ufual contents of air. It ferves to {hew, however, that a pump may very eafily be conftrudt- ed fo as to draw in frefh air, and this is all which was intended in making it. Since placing that pump, it has occured to the author, that in the cafe of ftoves and pineries. * The reader may afk, why this operation was not done? It is anfwered, becaufe the overlays of “ fragment glafs” are fo numerous and fo large, (each fragment pro- jecting an inch and often more over the next) that it would have too much darkened the houfe. ( 93 ) pineries, which have adjoining fheds, the beft way would be to have a kind of bellows fomething of the kind reprefented by fig. 6. plate II. placed in the fhed immediately behind the back wall of the houfe, and which could be eafily worked by a man moving up and down the lever a. The air would thus proceed along the tube and enter the hothoufe immediately under the top of the roof ; when defcending it would diffufe itfelf with the air which it al- ready contained. The top, underpart, and tube or nozle of this bellows, could be made of wood, and the fides of leather. And as from the width of the tube or nozle, no great degree of flrength would be requifite, and alfo little or no iron work neceffary, the whole expence of this machifre would be very trifling. Nor will the working of thefe bellows be laborious, as the air will not be nearly fo much ( 94 ) much comprefled in palling through the wide wooden tube, as through the fmali nozle of thofe ufed in fmithys, &c. SECTION III. Of the intention and mode of ujing the Bellows t or the Air-Pump . It is not propofed to introduce this im- provement univerfally into green-houfes, or peach-houfes, or into any glafshoufe of the fame nature; but principally, into pineries and fuch plant ftoves, as are heated by mak- ing fires during the whole winter feafon. It is thought by the author, that in houfes of this kind, two advantages will re- fult ( S5 ) fult from the air-pump or bellows, which deferve the ferious attention of all thofe who poflefs fuch hothoufes, and who wifh to fee their exotics, green, healthy, and luxu- riant. The firft advantage, though confiderable, is not fuppofed to be the greateft, — it is the faving of fuel. The fecond, is the advantage which will refult to the plants, or exotics, not only by giving them more frequently frefh air, to refpire in ; but, by greatly increaling its elafticity, and by introducing it in fuch a mild gradual manner, and of fuch a mode- rate temperature as will not chill the plants. For thefe beneficial purpofes, the gardener fhould, in ev ry day, which from its cool- nefs, will not admit of the houfe being ventilated with the open air, (and this will be ( 96 ) be the cafe nine days out of ten, in the winter months) prefs or force in a quantity of frefh air, with the bellows, having for- merly raifed the houfe fix or eight degrees above the medium heat, proper for the plants during the day. It is necelfary to repeat, that in pumping in this air, he fhould not only have a view to bring dowm the temperature of the houfe to the proper medium, and give frefh air to the plants ; but he fhould alfo have an eye to “ charging the houfe,” that is, filling it with double the quantity of air, which it natu- rally contains. The advantages of which, in promoting the vegetable refpiration, will be very evident, at once, to chemifts and botanifls, and it is prefumed will foon be feen by practical operators. In many hothoufes, which have not the interftices betwixt the glafs puttied, this lafl ufe of the air bellows will be fruflrated ; and even ( 97 ) even in the mofl exafl houfes it is not fup- pofed that they will remain “ charged” in the way mentioned for many hours toge- ther ; yet if we fuppofe them to remain more or lefs fo, for five hours every day, this will certainly prove of fuch advantage, as am- ply to compenfate for the trouble. In connexion with this plan, and for the purpofe of ventilating the houfe with air of moderate temperature, a long leather pipe could be got, with one extre- mity of fuch a fize, as to fit the end of the bellows tube, where it enters the houfe ; and with the other extremity, exactly fimilar to the rofe of a garden watering pot. This pipe being fixed on, and one per- fon working the bellows in the fhed, ano- ther in the hothoufe, might guide the ex- treme end of the pipe to any part of the houfe, or to any particular plant, which in ( 98 ) a more efpecial manner required ventila- tion, or a lhower of frefh air. Regard mult always be had that the air in the back fhed be of a proper or moderate temperature before this operation is com- menced. This can be accomplilhed, by keep- ing all its doors and windows clofe, by open- ing the furnace door, and by (hutting the extremity of the air-flue in the houfe ; but cautions of this kind are unneceflary to moft gardeners ; for they are generally fpeaking, a very attentive and intelligent clafs of men. It (hall only be further ob- ferved, for the fatisfa&ion of fome, that \ many gardeners and nurfery-men, who are in the pra&ice of railing young exotics and even green-houfe plants, ufe the common bellows as a ventilator, for the purpofe now mentioned. CHAP. ( 99 ) CHAP. IV. OF THE VENTILATOR. SECTION I. Of Ventilation . Ventilation, and giving frejlo air, have been generally confounded together in idea, and in practice unavoidably performed at the fame time. It has been already (hewn, however, that there is a wide difference be- N 2 twixt ( 1Q0 ) twixt adding frefh air to the houfe, and put- ting that air which it already contains, in motion. To accomplifh this laft purpofe, that is, to put the heated air contained in hothoufes in conflant motion, is the intention of the ventilator to be recommended. In hothoufes nature has been imitat- ed, more or lefs perfectly in mod things. Heat is produced from the furnaces and flues. Light is admitted through the glafs; rain is fupplied from the fyringe, or the wa- teringpot j dew, is raifed by pouring watei upon the flues, or, by fleam apparatus ; and frefh air is admitted at pleafure. But what makes up the want of thofe refrefh- ing and genial breezes, which fan and invigorate real nature. Surely that ponde- rous volume of frigid air, which peihaps, for an hour or two every day, invades the ful- try C 101 ) tty hothoufe, and as a rapid current rufhes through among the tender plants, can never have the fame falutary efFed as a breeze of a warm temperature. As well indeed might we fuppofe, that in Jamaica, a breeze from Iceland would prove genial to the fugar cane or the pine apple. It is granted, that, in the fummer months, the open air of this country will prove more refrefhing, than any mode of ventilation which we can fubftitute : and green-houfe plants may perhaps be moft advantageoufy ventilated bv the free admillion of the */ open air, for nine months in the year. But in nature, there is no fuch thing as vegeta- bles living, for three months in the year, without enjoying the breeze, as is general- ly the cafe with all green-houfe plants; and it is Bill more unnatural to think, that hove exotics which are deprived of this be- nefit for nearly nine months, can be equal- ly vigorous, as if they enjoyed what is na- tural to them during that time. By ( 102 ) \ l By carefully comparing vegetables in the open air, with thofe in hothoufes, or fuch as are in fheltered, with thofe in expofed fituations, it will appear, that the effe&s of the breeze are strength : which in herbaceous vegetables, is fhewn by “ bufhinefs that is, a broad firm like appearance, and numerous furface roots; and in trees is fhewn by bulk of timber, increafe and vigour of lateral fhoots, and flrength of furface roots. We fee in nature, that trees and plants in the fame foil and climate, and enjoying alike every other advantage, if they do not equally enjoy the breeze, if the one is in a fheltered or pent up, and the other in an open windy expofure, thofe of the former fitua- tion are tall, weak, unable to fupport them- felves, and unfightly, * while thofe in the latter * Unfightly only when viewed as fingle obje£ls, and as fpecimens of the particular kind of plant or tree. For no- thing ( >°3 ) latter circumftances are healthy, robuft and luxuriant. Now, this difference in effed, is totally independent of all other caufes; and hence, in hothoufes, fuppofing the natural foil, climate and fituation f , exadly imitat- ed, thing is farther from the author’s intention, than to fay, that in wooded dells or foreft fcenery, tall flender trees, fickly branches, or decayed trunks, contrafted, and fome- times grouped with others having huge trunks and ex- tended arms, have not a fine effect. As well might he transfer the idea to the human fpecies, and with not only that all mankind were of the fame height and thicknefs, “ Made in one mould, call in one frame but of the fame condition, age, colour, and /ex. •f Situation is a thing by no means properly attended to in the culture of exotics. It is certainly ridiculous to think, that the uniform Hope of a bark pit, or a green- houfe flage, which expofes alike to the fun, every plant which they contain, can anfwer equally well for plants and trees which grow on the fides of mountains, in low rich vallies, in thick woods, in fhady glens, rocky cre- vices, and on the fides of dark caverns. ( I0 4 ) ed, yet there cannot be a doubt, and we fee it in fa£t, that the want of the breeze is a material deficiency. In the very belt managed hothoufes, we obferve the plants tall, fickly, and unable to fupport themfelves. And one proof that this is owing to a deficiency of wind or breeze, is, that we fee the tailed: and molt flender green-houfe plants, when expofed to the open air for a few weeks in fummer, as they ufually are, be- come broad and bufhy, and in general firm, and have their Items greatly increafed in thicknefs, with a numerous addition to their roots: — this every gardener knows. The fame thing may be very evidently feen alfo by comparing peach houfes, which are “ forced,” or brought into a vegetating date early in the fpring, and thofe which are forced later, or left nearly to the natu- ral influence of the feafon. It will occur to the recollection of every one, who has been accuflomed ( 10 5 ) accuffomed to obferve them in both ffates, that the ihoots of the latter are always much the thickeft and moil luxuriant. Moil men confound the effects of the breeze, with the effects of light and frefli air. Light is that which produces colour in vegetables. Air is the medium in which they refpire, and on which in a confiderable degree they live. The motion of air, or what is called wind, by a mechanical effedt upon the whole plant, produces not fo much rapid growth, as vigorous buihy flioots : and in trees by the fame means it produces timber. Trees which are planted very thick, or in fuch fheltered fituations as not to be put in motion by the wind, are uniformly fo tall and flender, as to be good for no ufe in the arts. The fame thing happens with thofe trees and ill rubs, which naturally attach them- felves to fixed bodies, (fuch as walls, trunks of trees, life.) as the ivy, honey fuckle, LV. O and ( io6 ) and with any fpecies of tree, when it is artifU cially fix;ed, fuch as fruit trees trained upon walls, or efpaliers, new planted trees fixed to pofts, &c. Thefe cannot be put in motion by the wind, and of courfe, we always find that the diameter of their trunks and branches, makes little or no increafe. As the wind feems of fuch confequence to vegetation in real nature, the imitation of it in hothoufes mufl be of very confides able importance. It has already been Bated, that in favour- able circumftances, that is, in the fummer feafon, when the weather is of a tempera- ture not greatly below that of the houfe ; the ventilation produced by opening the fafhes, and admitting a free current of open air, is heft. But the intention of the ventilator is to put the heated air of the houfe in motion, fo ( I0 7 ) fo as to produce a breeze of warm air at pleafure. SECTION II. Of the Conjlru&ioh of the Ventilator . ILJnfortunately the author has not been able to get a ventilator conftru&ed in time for this publication ; he fhall here, how- ever, give fome ideas refpe£ling the forma- tion of one which he hopes will lead others to think on the fubjedl, and perhaps to in- vent a better one than he has any idea of at prefent. It need not be thought from this, however, that there is any great diffi- culty in contriving the parts of fuch a ma- chine, The author is perfectly aware of a O 2 mode ( 108 ) mode which would anfwer ; though he has deferred fome weeks giving orders for conftruding it, in the daily expedition of feeing Mr Andrew Meikle, of Preftonkirk, a fmgularly ingenious mechanic, whom he believes well qualified to give him fome ufeful hints, if not to invent one in all re- fpe&s better. At any rate, no time fhall be loft in producing to the public a proper machine for the ventilation of hothoufes. In the mean time, in order to lead others to the invention of fuch a machine, the fol- lowing thoughts are communicated. One kind of machine which the author thinks will aiftwer, is to be compofed of two parts. The firjl part is a fmall box of ma- chinery, about one foot fquare, nearly upon the / ( 10 9 ) the fame principle as the patent malting jack. ♦ The fecond part is a fan, three feet in diameter, fomewhat firnilar to that of a common winnowing machine. This is intended to be fufpended to the firft part, and thus the whole machine will be finilhed. It is propofed to be hung from the raf- ters, and to change its place once or twice a day, by this means varying the wind or breeze, in fuch a way as that none of the exotics might be injured from too great a current, or fuffer from a deficiency of breeze. This fan was to be fo contrived, as that by fome fmall alterations it could agitate the air, more or lefs violently at pleafure. There ( ) There is another machine which the au- thor is apt to think would anfwer fully bet- ter than the former. This one is propofed to be made upon a fimilar principle to the com- mon roafting jack, viz. to ad by the defend- ing weight as the power. The whole ma- chine is fuppofed to be contained in a box, not more than two feet broad, four or fix feet high, and three or four feet long. It is intended to be placed upon fmali wheels, for the conveniency of pufhing it along the paths of the hothoufe. The wind is fup- pofed to proceed from the top of this machine, through a tube in a horizontal diredion; and this tube, by a particular contrivance in the machine, is intended to turn continually round, fo as to diffufe the wind on every fide. In ufing it, its fituation is fuppofed to be changed as before, once or twice a day. It is thought that both thefe machines would ( III ) would require to be wound up by a key, once every ten or twelve hours. Other kinds have been thought of, fome of them to move by a fmall wind-mill, or fan, placed without the hothoufe, &c.- y but it appears probable, that either or both of thofe above mentioned, will be found to fucceed. section m. Of the intention and mode of ufing the Ventilator. f ]F rom what has been already obferved, little •more requires to be faid upon the fubjedl. A few hints however lhall be given, as they may may lead gardeners into a proper train of thinking on the iubjedt of air in general. As in nature, wind prevails principally during the day, and that especially in the time of funfhine ; fo in hothoui.es the ufe of the ventilator mull be confined almoft folely to the day. i . Becaufe in the winter feafon, and efpe- cially in green-houfes, where no inner roof- ing is ufed, putting the ah of the horde in rapid motion, during the night, might have fome little tendency to caufe it to give out heat : And, 2 . It is found, that the growth of vegeta- bles, which takes place principally during the night, is moil rapid when they remain at red, and in a modi atmofphere. It will readily occur to the gardener, that as the wind varies m the open air, blowing from different quarters, and in different de-. grees. t i*3 ) grees of flrength, fo ought it to be varied ill the hothoufe. This he will be enabled to accomplifh from the nature of the ventilator, which may be moved to different parts of the houfe, and fo change the quarter or di- rection of the wind ; — and which may be made to move flower or falter, and fo change its force. Nature muft alfo be imitated in refpeCt to the moifture of the air during wind. We generally find the air clear during a fmart breeze; It is a perfeCt calm in foggy or thick hazy weather, when the atmofphere is loaded with moifture, or during the fall of rain. Thefe and feveral other parts of the eco- nomy of nature which might be mention- ed are not to be followed merely at iuch times as the operator may clioofe, for this might often be counteracting nature. We P muft ( H4 ) muft never attempt to produce a dull thick foggy atmofphere in the hothoufe in a clear funfhine day. During the winter feafon, on the other hand, he muft withhold frefh water or dew from the exotics though it fhould rain hard in the open air. For this the natural climate of the different hothoufe plants muft be his guide, as well as the totally oppofite conditions of the plants themfelves : — thofe in the open air being at this feafon in a dor- mant ftate — thofe in the hothoufe being now, and at all feafons, in a growing, and confequently much more tender condition. But befides this general way of imitating nature, a careful gardener will confider the effects of wind not merely in producing firm bufhy plants and robuft timber trees, but alfo in carrying oft fogs, and damps, which in certain fituations and circumftances, tend to bring on putrefaction or decompofition and other difeafes in vegetables. This will teach him C ns ) him, that when any thing of this kind hap- pens with any plant, or in any part of the hothoufe, a more than ordinary ventilation is requilite. By a careful attention to the natural breeze, many other things refpeding the imitation of wind will occur, which fhall not be entered into at prefent. From a proper ftudy of nature alfo, the fafeft and moft complete mode of managing heat, rain, dew, fcfr. may be learned by thofe who fhall carefully obferve and refled; upon her beautiful economy. But a more full confideration of this, as well as the general fubjed, mud be left for the treatife on hothoufes. P 3 CHAP ( ) CHAP. IX. ON THE ADVANTAGES RESULTING FROM THESE ALTERATIONS. Having now defcribed the alterations which were made upon this hothoufe, and and alfo fhortly treated of the nature of thefe alterations ; in taking notice of the advantages which refult from them, it feems requifite to coniider the fubjed un- der two different heads : viz. ( * U7 ) 1 . The advantages which have refulted in this particular cafe; and, 2. The advantages which will refult in general. SECTION I. Of the advantages which have refulted from thefe alterations in the hothoufe belonging to Mejf Dickfons and Shade . The peculiar and uncommon * circum- ftances which rendered this hothoufe unfa- vourable * It is very uncommon to find fuch a fmall hothoufe with not only the back •wally but the ends and front of mafon work, and even part of the Hope upon which the fafiies are placed covered with deals. See page 1 2. ( 2 1 8 ) vourable for fhewing the effect of the al- terations have been already noticed. The effects which have been produced however, {hall be inferted without the leaf! deviation from truth. Should the leaf!; degree of dubiety arife in the mind of the reader, he has only to examine the hothoufe referred to, himfelf, and enquire of the particulars at Meff. James or George Dickfon, or the lad who manages the houfe : or though he fhould be at fuch a diftance as to render this difficult or inconvenient, he may em- ploy fome perfon in Edinburgh to vifit the hothoufe, and make thefe enquiries in his room The firft and mofl linking effedt of thefe alterations, was the leffening of labour; for. Formerly * This is inferted principally for the fake of thofe in England who may purchafe this work. The utility oi ihe alterations are already pretty generally known in Scotland. I ( "9 ) formerly the fire had to be ftirred up, and frefh fuel put on feveral times a day, and alfo every night at eight o’clock; and the fuel chamber being then large, there was a continual danger of railing the houfe to too high a temperature. This kept the lad (John Roger) perpetually employed about the hothoufe. After the alterations were made, in the fevere weather of the end of December and the beginning of January, it was never found necelfary to go to the fire above four times a day: viz. The firlt time in the morning to put on fuel, the fecond time in about half an hour afterwards to open the valve in the furnace door, the third time in the afternoon to put on another fire, and the fourth time about half an hour af- terwards to fhut the valve, which commonly happened to be at the time of leaving off work. At ( 120 ) At prefent, (end of February) it is only neceffary to go twice a day to the fire place ; for one fire ferves during twenty four hours. The fecond principal effedf, was the fay- ing of fuel. Formerly (in the beginning of December) one barrow load and a half, in twelve hours* and in very cold weather, more was necel- fary. After the alterations were made (in De- cember and January as before) a barrow load ferved more than fifty hours : at prefent (Feb- ruary) a barrow load ferves fixty-two hours. This appears a faving of more than three fourths of fuel ; but when the difference of temperature of the atmofphere, and alfo the difference of temperature produced in the houfe, are taken into account, it appears, that a faving of four-fifths of fuel is effe&ed. The ( I 2 * ) The next advantage is, the having of time. Formerly one lad was conftantly employ- ed in attending to this hove and the green- houfe, and frequently he required aflift- ance. In the courfe of occaiionally calling to fee the hothoufe, the author has frequently not found any perfon at hand, and Mr Dickfon has informed him, that ever fmce the alte- rations were made, the keeper has been every day more or lefs employed, in diftant parts of the nurfery. The fourth advantage was the lelfening of rifle. Before the alterations were made home accidents were conftantly happening, with thofe plants which were neareft the furnace. Two or three yards of the flue, indeed, was always left without any plants, as they were in continual danger of being fcorched. On the other hand, thofe plants kept at the oppoftte end of the houfe, were Q. in i C 122 ) in continual danger of being too much cooled. At prefent the houfe is equally warm throughout, as is fully known by a ther- mometer which is kept at each end, and in the middle. The front flue is uniformly hot throughout with pots of plants from one end to the other, which never fuftain the leaft damage. The next advantage is the fuperior health of the plants, which is the natural efFedt of a more fceady climate and more frefh air. Some may think, that fufficient time has not elapfed to judge in this matter. And there may be fome truth in this, as it is not yet two months fince the alterations were made. But, fo confpicuous has been the fuperiori- ty of the vegetation during this laft period, that it has aflonifhed every one who ha§ feen it. Sect. C 1 23 ) SECTION II. On the advantages which will refult from thefe improvements in general cafes . To know this, it is only neceffary to af- certain what relation the hothoufe belong- ing to MefT. Dickfons and Shade, has to the generality of hothoufes. It is prefumed, that none who have feen this hothoufe, or confidered the defcription given of its hate previoufly to making the alterations, will deny, that it was in a dou- ble degree better calculated for faving fuel, than hothoufes in general. This being granted, it is plain that the faving of fuel muft in general be more than ( 124 ) than double what happened in this cafe. So that in all large hothoufes, * it may with perfect fafety be afferted, that a having of more than nine-tenths of fuel will be effect- ed . And this the author will undertake to do in any hothoufe, either in England or Scotland, containing above a thoufand cu- bic yards of air, which is the cafe with many vineries and pine ftoves f. It is in a great meafure unneceffary to add any thing to what has already been faid, refpeding % Becaufe as the dimenfions of the houfe increafe, the proportion of fuel faved, will increafe alfo. f The author will make one fingle exception, which is the pine Hove at Woodlands, Surrey, eredted by Mr David Stewart. At the lame time, though he is perfectly fatisfied he could not fave nine-tenths of the fuel ufed in that houfe, yet he is fully convinced, that by the ad- dition of the inner roofing, the faving would be very confiderable ( 125 ) refpeding the other beneficial confequences which will arife. The laving of time and labour is a pecuniary advantage, which in an extenfive range of hothoufes, will no doubt amount to a tolerable fum yearly. But the certain benefits arifing from the fu- perior health of the plants, and the fecurity from extremes, or rifk of any kind, are greater than can well be imagined. What are the fenfations of a botanifl on entering a ftove, where all the plants are of a confiderable indeed. And he is further of opinion, that by fimplifying the whole, according to his plan, time and labour would be greatly leflened, not to fay any thing about original expences, or the health of the plants. That hothoufe is, if I recoiled!, upwards of feventy feet long, and eighteen feet broad, and is wholly cover- ed and furrounded with glafs, During the winter and fpring months, a vaft quantity of heat muft efcape thro’ fuch a large furface of glafs, which the inner roofing would undoubtedly in a great degree prevent. ( 126 ) a pale yellow colour — where they are all drawn up into unfightly forms — where even the leaves and flowers do not afliime their true natural fhape, and where they all bear marks of difeafes ? How different muff his feelings be on en- tering one, where all is health and luxuri- ance, where the trees or fhrubby forts are each afluming their natural form, where the plants are tufted and bufhy, and where the natural colours and minute parts of each individual are ftrongly marked. Is there any difference betwixt the flate of a gentleman who poflefles a number of vineries, peachhoufes, and pineftoves, and yet is in continual fear of an accident which may deftroy all the fruit, — and ano- ther gentleman who in all human proba- bility is fure of a good crop ? CHAP. ( 127 ) CHAP. X. ON THE EXPENCE OF MAKING THESE ALTERATIONS. 3Perhaps none of the leaft advantages of thefe improvements is the eafe and economy with which they may be executed ; either in the cafe of altering an old, or already built hothoufe, or in ere&ing one wholly new. The ( 128 ) The expence of altering one already built muft depend a good deal upon the ftate of the flue ; as, in fome cafes it may require to be wholly taken down and rebuilt, and in others the covers only taken off, the fides heightened, and the u briggs” put in — adding the air-flue, never of greater length, than from the fire place to the other extremity of the houfe. As formerly mentioned, one fire place to a houfe, will in all cafes be fufficient. The furnace may be made upon a larger or fmaller fcale, agreeable to the propor- tions of the plan given in plate I. But one fimilar to that in the plate will fuffice for all hothoufes containing not more than a thoufand or twelve hundred cubic yards of air ; and indeed for moft hothoufes. The price of fuch a furnace is juft L2. : io. It may be had at the Edinburgh Foundry, or at Mr Dalziel’s, (Cabinet Maker,) Chapel-Street, London, on en- quiring ( 129 ) quiring for Loudon’s Improved Hothoufe Fur- nace, which words are printed upon the door of the furnace. The improved afh-pit door, made according to the figure given in plate I. and the grate, are had along the above furnace, and are included in with the price. The alterations made upon the flues and furnace in Dickfons’ and Shade’s hothoufe, were executed by workmen belonging to Mr Gilchrist, Builder , Head of Leith Walk , Edinburgh ; whom the author can fafely re- commend to gentlemen for the execution of fuch improvements, and for building in general. Mr G. can fend workmen to alter furnaces and flues to any part of the coun- try ; and when gentlemen have not an in- telligent mechanic in their neighbourhood, who can work from drawings, or from the plates, given at the end of thefe flieets, this will be found the fafefi and moft economi- cal mode of procedure. R The ( *3° ) The expence of the inner roofing is the fame both in the cafe of altering old, and making new hothonfes. The coarfe flannel can be had from E. ^Collier & Co. Lawn Market , oppofite Bank- Street , at fixteen or eighteen pence a yard, the fluff being twenty- feven inches wide. This company have had proper directions for wetting the flannel with alum, to pre- vent its taking fire. The pullies, rings, &c. are to be had from Mr James M‘Lean, Ironmonger , High- Street. Mr James Philip, "Joiner , Broughton , un- derfcands the mode of fixing up the inner roofing, and of determining the proper fhape and dimenfions of the curtains which compofe it, to any form of hothoufe. Mr !’. is alio qualified to conftruCt the air-pump or bellows, and the author can recommend him for any tiling eife, either in the way of hothoufes, or in his profef- fioit ( T 3* ) fi on in general, with the greatefl certainty that he will give much fatisfacfion to thole who may favour him with their employ- ment. Having noticed this much refpe&ing the expence of each of thefe improvements fe- parately, fome remarks fhall be added re- fpedting the general expence. In the cafe of Dickfons’ and Shade’s hot- houfe, where, from the novelty of the plan, fome blunders were made by the workmen ; and where, from the inner roofing being ere&ed in four different ways, before fixing on the prefent mode, the amount muff be much more than what can generally hap- pen. Notwithstanding, however, the whole expence of alteration did not amount to twenty pounds. The author conceives, that from fifteen to thirty pounds, will generally fufhce for R 2 altering ( »3* ) altering any ordinary fized liothoufe in Scotland. In England the additional ex- pence will be very trifling. The entire expence of ereding a new hothoufe, according to this plan, will not be more than half the above fum, or perhaps eight or ten per cent, added to the whole expence of the houfe. In the courfe of giving diredions for ex- ecuting thefe alterations upon hothoufes, the author has found Mr James Gould, Builder, Muithill, near Crieff, in Stirlingfliire, a very ingenious and intelligent perfon. Mr Gould has for fome time pafl been in the pradice of building hothoufes in the ordinary way. He has now had fuch direc- tions from the author, and has given fuch clear proofs, that he underflands the nature of the alterations, that he can warmly recom- mend him to fuch gentlemen of the furround- ing country, as may be pleafed to adopt any part of his plan. The ( *33 ) The author is forry he cannot now refer the gentlemen in England to workmen in London and York, who could execute the improvements in the fame way, as thofe he has juft recommended in Scotland. In a few weeks however, the author expects to have this in his power ; and he fhall take care, that the names and addrefs of fuch artizans as he may fix upon, fhall be public- ly advertifed, for the benefit of all thofe who may wifh to make the alterations, with no trouble and little rilk of blunders. In the mean time, any gentleman who may wifh to alter his hothoufe immedi- ately, and with his own workmen, if he finds any difficulty, by fending to the au- thor a general fketch, or defcription * of the prefent * This can be done in very few words as follows : Length — breadth — height of front glafs — height of back wall— two furnaces, one in each end, placed behind, •.he back wall. The flue of one, is led round the houfe, immediately ( 134 ) prefent ftate of the houfe propofed to be al- tered, fuch directions, plans, or models fhall be fent, as are fuitable to the cafe, and as will be clearly underftood. The author’s mode of conftru&ing the fire-place and flue, is fo plain as to be underftood by the Ample ft mafon or bricklayer. CHAP, Immediately within the ends and front glafs, the other makes feveral courfes in the back wall. Such a defcrip- tion as this is amply fufficient. ( !35 ) CHAP. XI. ON OTHER IMPROVEMENTS WHICH MAY BE MADE IN HOTHOUSES, SECTION I. Of the Introduction of Improvements in Hot - houfes . That the conftrudtion of hothoufes, is very imperfectly underftood, among thofe who are generally employed to erect them, will appear very evident, to any who fhall invef- tigate the fubjedt in a very flight manner. Kof ( 13*5 ) Nor will this appear furpriiing, when we conlider the very recent date in which they have become general in gentlemens gardens. It is prefumed, that there were few’ green- houfes in England before Mr Evelyn eredted his Confervatory, at ********, near London. Now the very fame general form has uniformly been followed, till within, thefe two or three years. Not indeed ex- actly the fame conftruction, for certain iron u pipes” which Mr E. ingenioufly, but ra- ther unfuccefsfully introduced for the pur- pofe of fupplying heated air, have been re- jected ; and this evidently without that en- quiry into their intended ufe, which was due to every fcheme devifed by that great man. The hrft hove eredted in Scotland, was that which belonged to the late Mr James Justice *, at Crighton, near Edinburgh, and * A great enthufiaft in gardening, particularly in tht? culture of flowers. ( 137 ) and if we obferve the plan of this hothoule, &s given in Juftice’s Britifh Gardener, we fhall obferve little or no difference between it, and the mod; improved conftru&ion of pine ftoves at the prefent day. With refpedt to books on hothoufes, there has never yet been publifhed any thing in the way of enquiry into the principles of their conftrudtion and general management. Mr Evelyn in defcribing his confervatory, gives two or three hints refpedting the pro- perties and management of air, which are deferving of attention, But in the feveral books of deligns, which have been publifh- ed, and are to be had at Mr Taylor’s archi- tectural library, Holborn, London, not a word is added refpe'Cting the principles, or even the properties of the defigns recom- mended. Indeed thefe defigns are imprac- ticable, and fuch as could not anfwer the purpofes of horticulture. The natural confe- S quence ( 138 ) quence which has ever followed hothoufes, deligned by mere houfe architects . ' ; • i I The plans given and recommended by Mr Abercrombie, Mr Speechly, and feveral others, anfwer better; but, they contain no deviation from general practice ; nor do we find that thefe men have ever thought or written upon the principles of their con- it ruCtion. The fame obfervations will apply to the deiigns recently publilhed, by Mr Walter Nicol in his Forcing Gardener *. It is pro- per to remark,however, that thefe deiigns, tho’ exaCtly upon the principle with thofe men- tioned above, are perhaps, upon the whole, better adapted for the purpofes of forcing. At any rate they are preferable to any thing that has hitherto appeared in this country. The * By Creech, Edinburgh 1802. ( '39 ) The public are greatly indebted to Dr Anderson, for the many ingenious hints contained in the account of his patent houfe, * and this fingle volume is certainly of more importance, than all the other de-? figns or books upon the fubjedt which have yet appeared. But though in fome of the warmeft counties in England, the Dodtor’s hothoufe may, perhaps fucceed for a year or two after the houfe is eredted, it is the humble opinion of the author, that it will never come into general ufe. In different parts of the ifland, there are, and have long been, peculiarities in the conflrudtion of fome hothoufes, which, had they been underftood and attended to by planners, would, long ere now, have made a material difference in the conftrudlion of hothoufes, S 2 At * JPublilhed by R. Cumming, Holborn, 1803. ( HQ ) At Abercairnie, near Crieff, in Stirling- Ihire, heated air introduced by the furnaces and flues, has long been ufed in a peach- houfe. And though the conftrudion by which this is effeded, is extremely imper- fed: *, yet the end is anfwered in a confi- derable degree, and a tolerable faving of fu- el is produced. The author has been told by a gentleman (Mr L**, Hammerfmith) in whom, he can place the utmoft confidence, that heated air was introduced into a hothoufe in the neighbourhood of Manchefter, near forty years ago ; and as it is probable there may be fome other cafes in England, which has not yet come under the author’s eye, it is likely, * Imperfeft, but not fo completely erroneous, as at Archerneid, Eaft Lothian, where heated air was lately brought from the furnaces in a vacuity immediately un ) It is probable, however, that the bed way, when a row of cottages can be com- manded, is to place the glafs upon the wall only, forming one fuch houfe as A which could be eafily heated by the air from the fires, 13c. But in fmall gardens in towns, or in mere plots, or court yards, it may often be agreeable to have a green-houfe or vinery upon the top of a houfe or liable, where to place glafs upon its fides would ferve no purpofe. The roof alone mull be covered. It may be remarked here, that there can hardly be a cafe fuppofed, either in a town or village, where the hothoufe could not be warmed by part of the air collected around either the kitchen fire-place of the houfe to which it belonged, or round fome other adjoining fire-places. This the author confiders of confiderable importance to many ( I 57 ) many in London, who have, or who may intend to build hothoufes. section in. Of heating hothoufes by Steam , and of Steaming in general. IPerhaps the operation of {learning hot- houfes, by boilers was no where carried on more extenfively than at Dairy, by the late Mr Mawer, a well known Planner and Nurferyman ; as the author was for a con- iiderable time his draughtfman and general affiftant, he had every opportunity of ob- ferving the whole procefs, from the eredion of the boilers in 1794, to the death of Mr Mawer in 1798. It ( ’58 ) It is not the intention of this feclion to treat fully on the fubjed, but merely to hate the general refult ; becaufe many per- fons more fond of fpeculation than well grounded in fcience, think that fleam may be ufed with immenfe advantage in hot- houfes. At Dairy we had five very large boilers, which fleamed two pineries, two peach- houfes, and tvco vineries ; we tried boilers of a variety of forms, and various modes of fup- plying them with water. We alfo tried cop- per, tinned , and white iron pipes for conduct- ing the fleam to the houfe. We tried alfo to heat the houfe by filling it with vapour from the pipes, and alfo by making the va- pour pafs through it, and thus heating it by the heat emitted from the pipe alone. In the pineries, we had alfo fleam pipes in the barkbed, the vapour of which we could either allow to be fpent among the bark, or to difperfe itfelf through the the ( >59 ) air of the houfe — we tried alfo a great variety of other ways, and made a great number of experiments both as to its effeds and as to the expence attending it, (fome of which experiments were fent to the Board of Agriculture.) But the refult of the whole, although never confefled nor made public, was, that u Steaming by boilers is not only un-° necejfary , but an immenfe expence Steaming by boilers is totally unneceflary ; becaufe as every gardener knows, a hothoufe can be fufficiently filled with fleam at all times, by pouring water upon the flues or even upon the floor. If it is unrtecedhry, it is evident the whole expence of the apparatus, which is con- fiderable, and the trouble and rifk, which are enormous, mull be all thrown away. The author therefore is clearly of opinion, that it is the mofl abfurd thing imaginable, to ered boilers for fupplying hothoufes with v fleam. ( 160 ) fleam. If any kind of implement or uten- lil were even to become necefiary a car- ron plate, with edges one inch in height of any covenient fize, may be placed upon the hotted part of the flue, and filled with water. A vafe or any utenfil, clofe fhut at top, and with a very fmall hole about half an inch from its bottom, may be placed upon it, which will thus keep the plate condantly covered with water, and at the lame time allow none to run over. A plate of this kind containing fix fuperficial feet, and placed upon the hotted part of the due, will produce abundance of deam, for a very large houfe — and when deam was not want- ed, it would be in no danger of being rent by the heat, as boilers continually are. Steaming of hothoufes, whether accom- piifhed by boilers, carron plates, or what is certainly better, mere watering in the houfe, is of great importance when properly done i and ( ) and equally dangerous when done at an im- proper feafon and in a wrong manner. It mud be confidered, that when the houfe is fufficiently filled with fleam, the greater part of the heated air is driven out — and that as foon as the fleam condenfes, which it does in a very rapid manner, the fpace which it occupied is replaced with cool air from without. Steaming therefore in winter, in cold wea- ther, and particularly in the night time, mufl be very dangerous; for it is evidently next to impoffible to keep up the houfe to a proper temperature in thefe cafes. In moifl weather, and in the winter fea- fon, fleaming is alfo very dangerous for bring- ing on the “ damp” as every gardener knows. At all times it has a tendency to dirty the glafs and rot the -wooden work. But on the other hand it is mofl excellently adapted for deflroying and preventing infedts ; par- ticularly the redfpider; and like the dew in ^ the ( 162 ) the open air, it is admirably calculated to promote vegetation in every dage from the bud to the fwelling of the fruits or feeds. The air in hothoufes fhould never be more charged with fleam, than the open air, ap- pears to be charged with dew in the even- ings. Nature affords the bed examples and indru&ions for {learning. i To procure a flow conflant fleam, may be thought by fome a matter of difficulty, as it is not obtained by pouring water upon the flues, which may be very proper fome- times, but by watering the more cool parts of the houfe, as the floor, paflages, 1$c. or by giving the whole plants and houfe a gen- tle fliower with the feringe. No rules can be given equal to what every one may learn by attentively obferving the dews and evening fhowers in the fpring and fummer months. And indeed a careful at- tention to the date of vegetables in foggy, clear, blowy, and rainy weather, are of great ( 1 63 ) great importance in directing our practice in the hothoufe ; every operation performed in which fhould be in imitation of the more perfect economy of nature. It is eafy to conceive, that if a hothoufe were infedted with infedts, they might be eradicated by {teaming it two or three times with fome liquid, the fleam of which would prove deleterious ; or by placing in it retorts charged with fome deleterious matter, to be heated by lamps, which would foon fill the air wit.* a noxious gas ti.at would de troy all the infedts without the leaft degree of trou- ble in fhifting the plants. This fcheme would probably fave a vaft deal of labour and ex- pence. It is needlefs to obferve that a degree of caution would be neceffary in entering the hothoufe after this operation. The fafhes ought to be let down, or pufhed u , and the doors thrown open to admit a free current- of air before any perfon ventured in ; and X 2 even ( 1 64 ) even afterwards a brifk fire fhould be light- ed and the houfe well watered in order that a firong fleam might carry off every remain- ing noxious effluvise. At Dairy we never had occafion to try this experiment, for excepting a few of the fcaly infe&s (coccus) we never had any other. The coccus is completely eradicate ed with foap finds and fulphur. Confiant fteaming rots the blofioms of ftrawberries, injures fucculents, as Cactus, Aloe, &c. and deftroys the arcfma or flavour of fruits, when too much ufed at, or near, their ripe ftate. A mode of ufing fleam will be detailed in next fe&ion, which the author conceives will be very advantageous. SECT. ( 16S ) SECTION IV. Of a new plan for growing Pine Apples . Of all the different kinds of hothoufes which are made in this country, pine- ffoves are the moil expenfive, both to eredfc at firft and manage afterwards. There are three things which have ren- dered them more expenlive, when firft made, viz. i. More furnaces, and a greater length, or more windings of flue are required than in other hothoufes, in order to produce the higher ( 166 ) higher degree of heat requifite for maturing the pine apple. 2. The expence of the pit for the bark in which the plants are “ plunged” or in- fer ted. 3. The expence of paved paffages around the houfe. The great expence which is incurred in the future management of the pine-ltoves, is owing to the following caufes : 1. Attendance being neceflary through- out the whole year, and conftant fires being requifite during three-fourths of it. Thefe 0 two things may be greatly lefiened, but can never be fully removed. 2. The expence of the renewal of the bark in the pit ; and, 3. The ( i6 7 ) 3. The continual expence attending the operation of renewals, and of turning over the bark when it cools, fo as to regenerate fermentation, and thus produce a frefh heat. The original and after expence of the bark, and a confiderable part of the expence of attendance in general, the author hopes will be effeded by the following plan, which will anfwer either for altering ftoves already built, or for ereding new ftoves, or pine pits. 1 . The general form of the hothoufe is of no confequence as to this fcheme. But whatever that may be, an inner roofing, i$c. are fuppofed to be ufed, and the furnace built as formerly direded. 2. Convey the flue throughout the houfe, as is reprefented in plate V. fig. 1. where a reprefents ( «68 ) reprefents the furnace, above which is the fhaft or chimney. The air-flue muft be continued upon the top of the flue from the furnace to b , where it muft terminate in an opening, which may be clofed or Shut by a “ dove-tail” iron Cover, or regifter valve to be afterwards de- fcribed: a fimilar opening muft be made at the other end of the houfe, as at c , of the fame fize, and with a cover fitted to it in the fame manner. The fmoke-flue need not be made above two bricks breadth in depth, but of consider- able width, fay two feet. Tyle covers of a Suitable fize, muft be had, or ftone covers will anfwer better where they can be econo- mically procured. The flue being thus finifhed, a large air- chamber of the breadth and length of the houfe, is to be formed around and above it, by flooring the whole houfe with pavement, or large tiles placed upon Supports^ as Shewn in ( i6g ) in fig. 2. plate VI. By this figure it will alfo appear, that the firft turn of the flue, upon which alone the air -flue is made, has its foundation fo much lower than the reft. The houfe being wholly paved, a paffage muft next be marked off, through the mid- dle of the houfe, above the openings which communicate with the air-flue, as fliewn in fig. 2 . plate V. This paffage forms the houfe into two beds or pits for the plants, viz. A and B. In each of thefe above the pavement may be laid broken bricks, flones, or (in England) flints, four or fix inches diameter, for fix or eight inches depth, above thefe may be laid two inches of rough gravel, — over that one inch of coarfe fand, and afterwards the foil for the plants. See thefe fliewn in plate VI. fig 2 . % The intention of thefe rough flones is to preferve an air-vacuity betwixt the earth in Y which ( 17 ° ) which the plants are placed, and the heated pavement. And the great advantage of having it formed in this way, is, that thefe Hones and gravel, Isc. will preferve the heat a much longer time, and completely prevent any danger of over-heating the roots of the pines. This will be guarded againft with abfolute certainty, by the cur- rent of air which will enter by holes made at equal diflances, in the paffage wall, as at f f ft plate VI. fig. i . and being rarified among thefe ftones will pafs off into the houfe by the upright tubes g g g, &c. in fig. 2. plate V. Thefe holes and tubes have each covers or Hoppers, neatly fitted to them, the ufe of which will appear afterwards. Water may alfo be poured in at thefe holes, in the paffage parapet, or by the tubes g g 7 which will raife a moift natural heat, (fo congenial to vegetation,) and will pafs out of the |ybes as fleam. In this way a moift heat, ( '7i ) equally falutary with that of bark, leaves, or dung, may be had, without the lead ride of producing thofe dangerous extremes to which thefe fermentable materials are liable; and without any of the trouble of renewing them, or of drifting the plants in order to dir up or augment the 44 bark bed." When the water is poured into the ruble done vacuity under the plants, by fhutting all the holes in the parapet, and alfo putting on the covers of the tubes, the deam gene- rated would afeend through the gravel and fand into the plant-bed : And there it will be condenfed among the earth and the roots of the plants, which would prove very beneficial. Even when no fire is ufed by pouring in wa- ter in this way, (although the precaution of fhutting the hole and tubes w T ere not taken,) it would prove or great advantage to the plants, by producing a mold 44 natural” heat in the foil. Y 2 The. \ ( 172 ) The tubes could be left open at pleafure, and then the water poured in would fill the houfe with fleam. Or when the houfe was too warm they could be fhut, and then the heat would be retained, &c. So that inde- pendent of the moifl and uniform heat pro- duced in the bed by thofe tubes, and by the vacuity, the temperature of the air of the houfe could alfo be raifed or lowered at pleafure. There are alfo openings in the paffage which communicate with the large cham- ber that furround all the flues, by opening which the whole heated air can be admit- ted into the houfe at once * Any perfon capable of refleding upon the * ^ is almoic needlefs to add, that by pouring in wa- ter in thefe openings, the air given out from this large chamber will aifo be moilL ( i73 ) the fubjeft, will perceive, that from this large air-chamber, and the large mafs of mafon work, which will be continually hot, three confequences will follow of the utmoft importance: viz. 1. During the feafon when fires are ufed the temperature of the houfe can be raifed at pleafure. 2. There can be no danger of overheat- ing the houfe. 3. During the feafon fires are ufed, fleam could be produced in the greateft abun- dance, by pouring w T ater into the air-flue by the openings k k into the paflage. But fhould it be found that ' thefe advan- tages will be produced, and the author has little dcubt but they will, there are others which will alio refult from the fcheme. The ( > 7 + ) The plants which are intended to come into fruit, in thefe hothoufes may be planted at proper diitances among the earth, without being potted. And as for fome time after they were planted, the fpaces betwixt them would be very wide, pine plants in pots might be plunged there, until the plants intended to remain and produce fruit, grew fo large as to cover the furface. Thofe in pots might then be removed to hotbeds or pits, where they would remain until they were required to replace any which might have fruited, &c. This method of placing plants in pots among thefe planted in the bed, will be un- derftood by the following diagram, where o reprefents the plants in pots, x thofe planted in the bed. C *75 ) oxoxoxoxoxoxox xoxoxoxoxoxoxo oxoxoxoxoxoxox xoxoxoxoxoxoxo oxoxoxoxoxoxox About lix or eight months before the plants were intended to come into fruit, thofe in pots fhould be removed, and then the others would remain thus, x x x x x x x x x x x x x x x x x xx x x x x x x x X X X X X x Some gardeners will produce as an ob- jection to this mode of “ plunging out the plants” in the bed, that “ hereby they are prevented from coming into fruit fo foon as when grown in pots.” But the experience of feveral gardeners in England proves, that Vhis \$ owing to the plants being put into an improper (176 ) improper foil— that is, a foil too rich, and deficient in fand. But even in a rich foil, fuch as one compofed wholly of rotted leaves, many gardeners know that if when fruit is lpeedily defired, the plants have their roots cut round fix inches from the ftem or centre of the plant, they never fail to “ fhew” fruit foon after. Another advantage, and one of no fmall confequence for the health and beauty of the plants, and the flavour and magnitude of the fruit is, that by ufing earth, in place of bark, the plants may eafily be placed on a Hope correiponding to that of the glafs, which will bring them all equally near the light. By having a paflage in the centre of the hothoule only, in place of one around it, as fhewn fig. 2. plate V. and fig. 2. plate VI. nearly one third more pines can be grown in an ordinary fized houfe. It ( J 77 ) This plan for a pine-hove, the author conceives will coft much lefs when eredied, and prove afterwards more economical than any in prefent ufe. While at the fame time he thinks it will produce a lar- ger quantity of better flavoured fruit. Befldes thefe advantages there are feveral others which the author thinks would at- tend this mode ; but thefe, and fome mi- nute particulars refpedting it, he fhall omit at prefent, until he finds an opportunity of putting the plan in practice. Fie cannot however, avoid giving it as his opinion, that if pits or hotbeds were uniformly con- flrudled according to this mode, though in fome cafes it would perhaps be a little more expenfive at firfi, yet it would fiicceed much better, produce healthier plants, larger and better flavoured fruit, — do away all riik and danger from extremes of heat or cold, and fave much labour, time, and expence. 2 Sect, ( 178 ) SECTION V. Of an improved pit for growing young Tines , Cucumbers , Melons , &c. or for forcing fruits or flowers. preferring in view the principles o the pine-hove, recommended in the preceding Se&ion, the author prefumes that a pit for growing young pines, raifing cucumbers, melons, for blowing early flowers, or for any fuch purpofe, may be made, as fupe- rior to thofe in common ufe, as it is fup- pofed the pine-dove will be. A ( *79 ) A plan and alfo fe&ions of this kind of pit are given in plate VII. which are rendered clear by the letter prefs explanations. It is fuppofed a hundred feet long, and is divided into four compartments, all of which are heated by one furnace. Thefe diviflons can be kept at the fame, or of dif- ferent degrees of heat, by means of the heated air collected around and near the furnace. It will be feen in fig. i . plate VII. that two flues proceed from the fame furnace, and enter immediately into two different diviflons of the pit. The heated air collected around the fur- nace and flues, in thefe two diviflons may be allowed to efcape into any one of the four apartments of the pit. This is accomplifhed by keeping all the different regifters flmt, except the one in the diviflon in which tlje air is to be ad- mitted : or, the heated air may be perrnit- Z 2 ted ( i8o ) ted to enter into two, three, or the whole of the divifions at pleafure, by properly opening and fnutting the valves. The intention of the two flues which proceed from the furnace, is in cafe it fhould feem requifite to heat only one half of the pit at a time, or to produce an early and late crop of melons and cucumbers. When one half of the pit only is to be heated, one of the dues muft be flopped by bricks or clay, and the air regiflers in the cold half cf the pit kept conflantly fhut, in order that the whole of the heat- ed air generated, may be conveyed to the heated divifions. When one half of the pit is to be raifed much hotter than the other, as may often happen in the cafe of forcing different plants, or growing different exotics, one half the throat of the due which leads to the half to be lead heated, can be built up, which ( i8i ) which will permit only one half the quan- tity of fmoke and heat to enter it. By means of the air-flue and the two fmoke-flues, the four diviiions of the pit may very eafily be kept of four different temperatures. For example, fuppofe that three-fourths of the fmoke enters one flue, and only one-fourth the other, (from its being half clofed ;) it follows, that the heat of two- divifions of the pit, muft be as three, and that of the other two as one; and the fame may be faid of the heated air in the flues. Now, fuppofe all the heated air generated by three-fourths of the fmoke allowed to pafs into one of the hotteft apartments, and all the heated air gene- rated by one-fourth of the fmoke, let off into one of the coldefl: apartments; it follows, that there will be four different temperatures in the pit. The flrft in the diagram ( *82 ) diagram below A , fuppofed equal to one ; A, will be equal to two ; C to three, and D to four. A i B 2 C3 D 4 Pvofes and Cucumbers Straw- Pine Ap- and Afparagus. berries. pies. Melons. And thus in a pit fo conftructed will one furnace ferve for forcing afparagus, ftraw- berries, rofes, pine apples, cucumbers, and melons as in the above diagram. It is almoft needlefs to mention here, what mult be underftood from the im- proved pine-ftove, and from the plate, that each of thefe apartments is fupplied with fleam and heated air from the tubes. The holes for pouring in the water which is to ( 1 83 ) to produce this fleam, are {hewn in fig. 2. Thefe holes are alfo intended occafionally to admit air, to be rarified in the vacuity, but this muft be done with caution, parti- cularly in the winter months. The tubes which ferve for occafionally admitting all the heated air contained in the lower chamber, are alfo feen in the plate. The inner roofing propofed for this kind of pit, is fomewhat different from that ufed in large hothoufes. It is fimply a roll of woolen cloth, as fhewnfig. 7. plate VII. It is the breadth of three fafnes, and has a fmall round rod of wood, fixed to each end, on either of which it can be rolled up. Wires as before, are fixed under each raf- ter forit to Aide down upon. In the even- ing, when the inner roofing is to be ufed, a afh i s opened at one end, and a curtain in- troduced at the top of the pit, and laid upon the wires, and allowed to roll down, the operator holding the rod of one end m ( *84 ) in his hand. When it has rolled out, he fixes the two ends of the rod in the iron hooks fhewn by a, plate VII. fig. 6. he then intro- duces another curtain, and lets it down in fame way. Thus with almoft no trouble the whole may be made quite clofe and tight. In the morning when this roofing is to be removed, the operator goes to the top and rolls up the curtains, one by one. He may then either take them out of the pit, and lay them in a dry died, or in the win- ter feafon, allow them to remain in the pit, as fhewn by the dotted lines in fig. 6. No overlay is required in thefe cur- tains, as the one can eafily be made to projed over the other. But two or three fmall rods fhould be fixed to each curtain, parallel to the end rods, which when they are rolled down, will preferve them ftretch- ed out to the proper breadth. It is the opinion of the author, that this plan of a pit is perfedly pradicable, and he thinks the dvantages which it wiilproduce m ( 1 8s ) in faving much time, labour, and expence afterwards, and in maturing crops of fruits or early flowers, are of much importance to gentlemen who indulge in thefe things. He is certain, that in many places of Scot- land, by fubftituting pits of this kind, in place of long ranges of ugly dung hotbeds, the manure faved, if judicioufly formed into compofc heaps with peat, (as was long ago praflifed in Ayrfhire, and recently with great fuccefs by Lord Meadowbank,) would be no imconfiderable profit to fe- veral proprietors, and by poducing more corn or butcher meat, of fome advantage to the nation in general *. Sect. * For this purpofe no gentleman in the neighbourhood of peat or mofs, ought to allow a fingle cartfull of liable dung to be made into hotbeds. Nor indeed to be ufed in any way whatever, until it has changed or decompofcd a proper proportion of peat into manure. Gardeners may no doubt cry out for manure to the garden, but let them be told, that they can have this in equal abundance from the (f Meadowbank middens .” They will have no occaGon to A a ( 1 86 ) SECTION VI. Of an improved Peach-houfe. What has been fubmitted in the two pre- ceding fedions, though founded upon fads, may be confidered as in a certain degree, theoretical. The plan to be recommended here, as an improved mode of growing peaches, is founded upon experience. Every one knows that thele trees are al- ways “ trained” upon a wall or trellis. The pradice complain on other accounts, as he will foon find his labour greatly lefiened by the kind of pits recommended, which he may make of any dimenfions, or raife to any temperature, to fuit his purpofe. ( 1 87 1 pra&ice of training trees upon- walls or efpa- liers, in the open air, originated from a deficiency in our climate. By training and faftening the branches, the trees were preferved from violent winds, and when this was done on walls, the additional heat produced by the reflection of the fun was confiderable. Some may be difpofed to add as another advantage of training, that the branches and fruit are thereby uniform- ly expofed to the fun. But this is not true, for only one fide of the tree and fruit is fully expofed ; and, as this is completely unnatural to all trees *, it cannot be any benefit, but undoubtedly an injury. It is certain, that in fituations much expofed to the wind, fruit is never fo much fhaken..from efpaliers, as from ftand- A a 2 ard * Ivy, and one or two others excepted •, and here It takes place only with the fleam and leaves, the fruit being fmall and in a ccrymhis , is expofed alike on all Tides. ( 138 ) ard fruit trees : And it is equally certain, that peaches, nedarines, and apricots, can- not be matured in the open air of our ifland, unlefs trained upon walls. But it may be feen by any one who fball attend to the fubjed, and it can be proven from known fads in the vegetable economy, that in gardens tolerably fheltered, all fruit trees, at lead apples, pears, and cherries, always produce the greated quantity, and the bed favoured fruit, when left to adiime their natural diape; with no more pruning than what is necelfary to admit the fun and air among their branches. It mud follow from this fad, as well as from what has been al- ready alluded to, — the general economy * of vegetables,- — that peaches, nedarines, and other tender forts of fruit trees, could we plant them in a fuitable climate, mud prof- per ♦ * See the chapter on ventilation and giving air, and alio Mr Knight’s late experiments recorded in the Phil. Tranfaftions. C 189 ) per much better when, left to aflume their na- tural fhape, than when bound or faftened. One principal intention of placing vege- tables in glafs houfes is, that they may enjoy their natural climate, and why they are not alfo allowed to enjoy their natural freedom, can only be accounted for, by adverting to the deficiency of obfervation and reflection, in thofe men who generally have the direc- tion of gentlemen in matters of this kind *. When * It is tirefome to obferve the errors that men fall into, and the immenfe labour, difficulty and uncertainty, with which they think or reafon upon any fubjeCt, when they do not advert to nature. I think I may venture to fay, that there are few arts or fciences, and but few topics in each of them, but what we have a precedent for, in nature. And could men at their flrffc outfet in any fubjeCt, look boldly through the opinions, or works, of thofe who have gone before them, to nature herfelf, there can be no doubt that their ideas would be wonderfully enlarged, and that they would receive more light upon the fubjeCt by a few hours reflection, than thofe who may have devoted a whole life time to the trial of experiments, which, though fome of them might agree, with — yet the greater part were perhaps at variance with her laws. C 1 o° ) When the late Mr John Mawer of Dairy, defigned his own hothoufes, it happened from a particular circumftance in forming them into a range, that two large fpaceswere left betwixt the pine-ftoves and the narrow peach-houfes. As thefe fpaces were more eaf ly connected with the peach-houfes than with the pine-ftoves, it was thought they could be moft economically occupied a9 part of the former. But as there was no back wall in thefe fpaces, there was no way of growing the trees except as ftandards. Standard peaches therefore were planted two trees in each fpace which grew rapidly. To compare them minutely with the trees planned againft the walls, in the other part of the houfe is needlefs. It ftiall only be" obferved, that at Mr Mawer’s death, both the wall and ftandard trees had been fix years planted ; the former were pruned and otherwife treated in the ufual mode, and bore ordinary crops of fruit, fome years, few, m ( 19 * ) in others a confiderable quantity. The lat- ter never had one twig cut from them, and every year bore a double proportion of more beautiful, larger fized, and better fla- voured fruit, than thofe of the others. A double crop of fruit, and much lefs ex- pence of management (for training and pru- ning are tedious and expenfive operations) are certainly advantages which deferve fe- rious attention, whatever may be the cir- xupjftances which produce the overplus. But w T hen the caufe afligned for this fad agrees fo well w T ith what happens in ftand- ard and efpalier apples, and with the ge- neral economy of nature, it ought (and it cannot fail,) to convince every one capa- ble of reflecting on the fubjed, of the great fuperiority of the plan recommended* And confequently, that peaches, nedarines, when grown under glafs, fhould not be train- ed either upon the walls, trellis, or efpaliers ; but fhould be planted as ftandards, and left to ( l 9* ) to adume their natural ftiape and modes of growth. Suppofing this granted, fome hints fhall now be fubjoined refpecting the form of a houfe mod proper for this purpofe. The fil'd thing requifite is, that the houfe fhall be glafs on all fides, in order to admit light to every fide of the trees. That this may be bed effected it follows, that it fhould be made of an oblong form, and placed fouth and north ; and that the trees fhould be planted along the middle of the houfe. The next thing is, that the fide or upright glades diould be made as high as podible, in order that the trees may not be cramped or comprefied. This naturally reminds us, that the houfe diould be of a condderable height, at lead twelve or fourteen feet. In order that no ground in the houfe be lod, it feems preferable to plant dwarf-trees that ( *93 ) that they may fill the houfe with branches, regularly from the ground to the roof. No vines fiiould be planted againft the rafters in this houfe, but they may be plant- ed near the columns, and trained around them to their tops, where they may be left in a great meafure to themfelves, and in the progrefs of their growth they will hang down obliquely, and ftretch acrofs among the branches of the trees, form- ing curious and diverfified feftoons of grapes and peaches, and producing more fruit than if neatly trained in ftraight lines, upon a wall or trellis. I cannot avoid mentioning here, my utter difapprobation of the common mode of train- ing vines, by fixing all their fhoots in ftraight lines ; it is juft as unnatural as it would be, if a gardener were to infer t a plant of ivy in a park. B b and I 194 ) and endeavour to train it up as a iingle tree. A Angle glance at a vine plant, not to men- tion what we know of its habits when in a wild hate, will ihe v that nature never intend- ed it to grow in a ftraight diredlion Every gentleman in Scotland, (for in England it is better known,) ought to caufe his vines be trained crooked, or in a ferpentine direflion. This will make them fpring at, and fend out fhoots, from every eye, and produce double crops of fruit every year. See 'Forfyth on fruit trees. The plan for a peach houfe given in plate VIII. may be placed either with one end againft a wall, or made a detached houfe (as in the plates,'' in any part of a gar- den, or orchard. In this laft cafe the fur- nace can be concealed under ground, and the fhaft or chimney either carried up in a final! plate iron column, as in the plate, or ( l 9 5 ) or in a flue under ground, to the garden wall, or fome concealed fpot. It may be worth while to remark, that when the flue is carried under ground, a vacuity muft be formed around it, in order to prevent the bad effects of the damp or moifture of the ground, from retarding the draught of the fire. But though this particular form be re- commended as the bell conffrudtion of a peach-houfe upon the principle contended for, yet houfes may be made much in the ordinary way, and the trees grown as flan- dards with an effect, it is prefumed (and in- deed it is certain, as the peach-houfes at Dai- ry, where the ftandards fucceeded fo well, were placed againfl a wall, and were alfo greatly fliaded by the pine-ftoves) — much fuperior to the common mode of training a trellis. The principal thing to be attended to in this ( 19 6 ) this cafe is, to make the upright glafs of confiderable height, and the houfe not of great breadth. A fedion of fuch a houfe is given in plate IX. fig. 4. ; vines are fhewn trained upon a trellis placed againft the back wall. A plan agreeable to this fedion, is eafily contrived. It may farther be obferved, that ftandard peaches may be grown in the ordinary kind of peach -houfes ; or, indeed in any kind of hothoufe, by planting dwarfs, and as they grow up direding their branches in fuch a way as they may not come much in contad with the glafs. A thing more or lefs neceflary in every conftrudion of a houfe for growing ftandards, and which even requires to be done when trees are train- ed upon a trellis. A fedion of a houfe alter- ed in this way is given plate IX. fig. 5. Sect. ( *97 ) SECTION VI. Of architectural decorations in hothoufes . In Archite&ure which, is intended to pleafe the appearance of folidity and flrength are eflentially requifite. For this purpole it is a rule with architects, that openings be made a- bove one another, and that every folid appear of fufficient magnitude to fupport the fuper- incumbent parts of the edifice. When open- ings are very numerous in one part of a building, and when another part adjoining feen at the fame time, contains very few, it never ( 1 9 8 ) never fails to difpleafe. If the heavy part be uppermoft, it appears to crufh down that which is below ; and, if the light and open part be uppermoft, it appears difpropor- tionate to the reft and trifling. Hence it is that mafon work can feldom be allowed to appear in the elevation of hothoufes ; and thus old fafhioned greenhoufes, with ftone columns, and a ftone parapet above, gene- rally, if not always, look heavy and difplea- ling. Old greenhoufes with wooden columns and a dated roof, as well as modern glafs- houfes,when the back wall againft which they are built appears above them, look exceeding- ly ill. Cuftom cannot reconcile us to this effect, tho’ we are certain that no part of the wall bears any weight upon the glafs. Even the ftone coping when feen projecting over the glafs, is exceedingly ugly. The modern mode of carrying up fummerhoufes above jhothoufes, as at Preftonhall in Scotland, and Heythrope ( -199 ) Heythrope in England, in the opinion of the author at lead, have a very bad effect in fcenery ; behdes their incongruity when confidered as overlooking the kitchen gar- den, which certainly like the kitchen itfelf is not an object intended for beauty. Mafon work in hothoufes difpleafes alfo in another point of view. Every one knows that their ufe is to grow vegetables, and none are fo ignorant, as not to be aware, that plenty of light is elfentially requihte to produce fruit and flowers in perfection. Slate roofs then, thick ftone columns, or dead walls, tend to exclude this fluid, and of courfe to fruftrate the end in view. * : . • Thus it appears, that in hothou r es, every thing in the elevation which has a heavy appearance, or tends to exclude the light, in fome degree fruftrates their utility, dif- pieafes the eye, and confequently ought to be avoided. ( 200 ) F or this purpofe a good general rule may be, i* To let no mafon work be feen above the level of any part of the glafs. 2. That the whole of the roof be glafs ; and* 3. That the wooden workmanfhip be made as light as poUible. And it may be obferved, that this effed will be mod: perfed, when they are totally unconneded with any wall or done building, but merely raifed upon a level furface, built on all lides with glafs, and roofed with the fame material. Circular columns, are inadmiffible in the fidesof hothoufes ; becaufe they are unfuitable for fafhes or panes to Aide in, and becaufe they throw more fhadow than fquare ones. In all cafes fquare pillars are bed ; where they require to be broad, they may be paint- ed ( 201 ) ed green and covered with virgin’s bower. Paliflora or forne fuch fhrub. When fo nar- co vv as ot properly to admit of being covered with folia e, t;eymay be painted the general colour of the wood work, which in all cafes ought to be a v ello wifh white or cream colour. In hothoufes erected merely for the purpofe of utility, fuch as vineries, peach-houfes, &c. the workmanfmp fhould be plain, neat, and fubffantial ; in thofe defigned for ornamental produ&ions, fuch as the greenhoufe, exotic ftove, & c. elegance fhould be added. The mouldings, &c may be more numerous, and delicate, and every thing elfe in a correfpon- dency. The colour of the walls and flues fhould be brown or of oaker yellowy the ftage in the greenhoufe, and all the infide wmrk, except the roof and fldes, will have the beft effect in one of thefe colours, particularly under brown. The rafters, pillars, and trails, in the infide of ornamental hothoufes fhould G c always ( 202 ) always be covered with exotics Many beautiful fpecies of which are fuitablc for this purpofe, fuch as the Pafiflora, Morin- da, Jafmine, &c. Externally, they Ihould be painted of a cream colour, or yellowilh white. CONCLUSION. Three objects have been kept in view in the foregoing pages : The firft of them was to give fuch a de- fcription of the alterations made upon Dicksons’ and Shade’s hothoufe, as would enable practical men, to make the lame im- provements, ( 203 ) . provements upon others, or to build new hothoufes agreeable to this plan. The fecond objed was to give a fhort trea- tife upon the nature and effeds ot thefe improvements, that ingenious gentlemen might underhand the principles upon which they operate : And, The third objed was to fugged: improve- ments of another kind in hothoufes, — and thofe chiefly in the conflrudion of pine- ries, peach-houfes, and pits. With refped to the firfh objed the author obferves with much pleafure, that he has every reafon to believe, the improvements which he has made, will become general. In regard to the fecond and laft, he will be happy if any thing which he has written fhall contribute to enlarge the ideas of hot- houfe builders and gardeners; and hence ei- ther ( 204 ) ther diredtly or indire&ly, to the advance- ment of the art, and the benefit of gentle- men, who indulge in this amufing and ra- tional luxury. i EXPLANATION OF THE PLATES . , • - , -- ■ •' • : -» --- •«*- — * i - * o \ i \ k a EXPLANATION OF THE P L A T E S. \ PLATE I. Fig. i. London s improved Hothoufe Furnace . .The opening in each fide, which com- municates with the air vacuity. b The inner furnace door— 9 inches fquare. c Valve in the outer furnace door for admitting cool air to be heated upon the ( 208 ) the inner furnace door, and in the va- cuity around the fuel-chamber, &c. d Handle, which opens, {huts, and faftens, both doors at once. e e u Nobbs,” which are for the purpofe of fixing the furnace more fecurely in ma- fon work * Fig, * There is a beautiful variety through all nature, ■ythich a perfon of a contemplative mind is ever admiring. This variety in the animal as well as in the vegetable kingdom, is mightily fupported by contrails or pppofitions. The meadow walk at Edinburgh, is fhadowed by a row of {lately beeches, and though thofe trees when planted at regular diftances are all very much of a fhape, yet each of thefe, are fo different from one another, that a perfon might fpend in' a moll agreeable manner, a very long time in obferving their feveral forms and varied hues of green. In walking along the promenade and examining each tree, how much is the beauty of the whole heighten- ed, when near one end of the row, there fuddenly appears an old {battered trunk with its branches greatly fcathed, and ( 209 ) • Fig, ii. AJh-pit door to Loudon's Hothoufe Furnace. a The valve. b The handle. c Part of the frame on which the door is hinged, turned inwards and hooked at the extremities in order that it may be fixed more fecurely in the mafon work. Fig. i and curtailed.- 1 have already faid that during the time the alterations were making upon Dickfons and Shade’s hothoufe, I had been much amufed with variety of opinions,— by hearing the work- men relate what fome planners and others, purpofed as improvements. When the alterations were pro- ven to be of importance, and had in fome mea- fure attra£ted public attention, the author was again amufed by reports of what fome would call a worfe kind. But what a fund of entertainement did he partake of, when after thefe varied efforts to Jkath or ( 210 ) Fig. hi. G; ound plan of toe Fuel-chamber , Air-vacuity , and part of the Flue. a The fuel-chamber. b Furnace door. c Recefs for preferving live feul. d d Bottom of fmoke-flue. h h Vacuity around the fuel-chamber, and part of the flue communicating alfo with the furnace door. Fig. hlajl, a “ landfcape gardener” who happened to be get- ting fome common furnaces made, pleafed with the one recommended and fold at the foundry, quietly copied (as the Edinburgh Foundry people told me,) one part of it af- ter another, until at laft he produced a furnace almoft an exadf copy of that in the plate. This perfon affords like the. decaying trunk, a ftrong contrail to the reft of his profef- fion — and like it muft ftrikingly affedl the attentive ob- ferver, or moral painter. ( 211 ) Fig. iv. Vertical fediion of the fuel-chamber , fuppofing it finifhef and cut through in the direction a....b , fig* 3- a The afh-pit. b Bars of the furnace grate. c Upright rife of the flue above the recefs, for prefervingthe live coals, fee fig. 5. d Throat of the fmoke-flue. e Arch over the fuel-chamber. f Air vacuity. g A brick feen projecting down in order to fupport the upper arch. h Mafs of bricks around the whole, being part of the wall of the hothoufe, as may be feen by the dotted line a b, in fig. 3. D d 2 Fig. ( 2> 2 ) Fig. v. Longitudinal feciion of the furnace , and part of the f mole-fine, fuppofing them finifhed and cut dozen in the direction of e...f fig. 3. a Space betwixt the outer and inner furnace doors, in which the hole that communi- cates with the air vacuity is feen. b Fuel-chamber. c Fvecefs for live-fuel. d Grate. e Afh-pit. f f Handles of furnace and afh-pit door. i and g Vacuity for heated air under the u recefs” and part of the fmoke-flue. h h Smoke-flue, five bricks breadth in depth, x Air-vacuity above the fuel-chamber. k Contraction of this vacuity, immediately before the air-hue commences, / l The air-hue. 0 0 Sole ( 213 ) 0 o Sole of the furnace and flue. p p Supports of the flue. q Bottom of the fmoke-flue r Covers of ditto, which ferve alfo for the bottom of the air-flue. f Covers of the air-flue. Fig. vi. Section of the fmoke-flue and air-chamher [un- rounding it , fuppofing them flnijhed and cut through in the direction Jhewn by the dotted line c....d , in figures 3. and 5. a The fmoke-flue. b The air vacuity and flue. The fcale fljews the form and the dimenfions of the bricks fuppofed to be ufed in building the furnace , flues , &c. s Is the end of a common brick. 2 The edge of ditto. 3 The face or breadth of ditto. 4 The ( 214 ) 4 The end of a common flooring or pave- ment tyle. 5 The furface of ditto. 6 The fide and the front of a large tyle cover, fuppofed made on purpofe for co- vering that part of the air-flue, which from being continued on each fide of the fmoke-flue, is broader than the other parts. Where the air-flue is continued abo\e the fmoke-flue only, common tyles, as No. 5. will anfwer. In Scotland pavement will generally be had as conveniently as tyle of this flze. In England the tyle covers, will be moft economical. T LATE Tx. I. ( 215 ) PLATE II. Fig. i. Longitudinal feciion of the fmoke and air flue as eredled in Dickfons ' and Shade's bothoufc floewing principally , A A 7 ^ he “ briggs” or partitions in the fmoke-flue. B B The air-flue. a Sole of the flue, being bricks laid flat. b Supports of the flues (being bricks fet on edge.) c Sole of the flue being ordinary tyle covers. d End of the fmoke-flue being bricks on edge. e Cover of the fmoke-flue. f Intended to {hew heated air coming out of the air-flu?. Here, however it would be ( 2,6 ) be better to fix one of the regiflers defcrib- ed in plate VI, as they would anfw-r better for regulating the quantity of heated air admitted into the houfe. Fig. ii. Section of the j, 'moke-flue , and air-flue, fuppofing them, cut acrofs at the dotted line in fig, 3. plate I a The foie. b The fupports, c The fmoke-flue. d The air-flue. Fig. iii. A flection intended to fhew the manner in which the hriggs , or partitions , are formed in wide flues; and alfo how the heated air may be conducted in an earthen pipe in certain circumjlances. See pages 34 and 35 - a Sedion of the earthen pipe. b Briggs ( 2I 7 ) b Brigg or partition, c Hole under it for the fmoke to pafs through. d Supports of the flue. The covers and foie of this flue are fuppofed to be made of large brick or flone pavement. Fig. iv. View of the air pump ufed in Dickfons and Shade's hothoufe. a The pifton or fucker, with its valve for drawing in cool air. d The valve for allowing this air to enter the houfe. f One of the fides of the pump taken off, in order to fhew its internal ftrudure. e Handle of the pump. E e Fig. ( 218 ) Fig 5. Longitudinal fection of a broad fh allow flue , / ’hewing the bejl way of conjl rubbling the partitions . a The brigg or partition which comes down to the level of the foie of the flue. b A recefs, made in order that the fmoke may pafs under the partition. c Air-flue. d Pipes for conducting the heated air. e Supports of the whole. f /Smoke- -flue. I Fig. 6 . Seclion or end oj part of a hothoufe fuppofed to ' he altered according to the new plan, and having the air bellows. a The handle of the bellows. b The tube which leads the air to the houfe. c The C 2I 9 ) c The termination of this tube where the air enters the houfe. d Section of the inner roofing. i The wire upon which the curtains which compofe it roll down. f The cord by which they are fattened. g The ufual mode of coping the walls of hothoufes. PLATE E e 2 ^ 220 ) PLATE III. Fig. i. A view of one whole curtain , and part of a fecund mounted with rings , &c< according to the firjl mode of fixing up the inner roofing. a a The overlay. b h Rings fixed to the edge of the overlay. c c Hooks on which the rings are put when the curtains are let down in order to keep them clofe. d d Cord Tl.E. ¥ f //> 7 7)¥ J*' £/u/f A . £////> ( 22 ' ) d d Cord for pulling up and letting down, the curtains. e e Rod fixed to the lower end of the curtain. f f End of the curtain to be fixed to the top of the hothoufe. Fig. ii. Section or end view of a hothoufe [hewing the appearance which this firjl kind of curtain will have when let down. a The curtain the rings of which are feen. b The cord which ferves for drawing it up. c The wire upon which it is fupported. d The hook upon which the cord of the cur- tain is fixed. e Dotted lines (hewing the appearance which the curtain will have when tucked up, as more clearly fnewn fig. 6. plate III. f /Back w r all coped with (lone in the ufual manner. ( 222 ) Fig. hi. Form of curtain fuitable for compojing an in- ner roofing to a circular houfe. a b c The three pieces which compofe the curtain. d d The overlay with the rings, EsV. as be- fore. e e e Jointed rods which are for the purpofe of firetching the curtain to the proper breadth when it is drawn up. /'Ring at the top of curtain, to which is fixed the cord ufed for drawing it up. This kind of curtain being fuppofed to be placed at the bottom of the upright glafs. g The rings and cord for drawing down and tucking up the curtain, which pafs through a hole at the bottom, and not at the top, as in fig. i . Ftg. ( 223 ) Fig. 4. A fection J, hewing the appearance this lajl cur- tain will have when tucked or folded up. a The bottom of the front glafs or front- wall. b The curtain folded as it remains upon the front parapet at the bottom of the upright elafs until it is drawn ud. O x • c The wire upon which it is drawn up. e A pully, over which is put the cord ufed to draw up and let down the curtain. /The cord which is palled over the pully. ( 224 ) PLATE IV. Fig. i. A view of part of a houfe with the inner roof- ing put up , according to the mode oj fix- ing thg curtains upon rollers . a a Coping of the wall. b b Rafters of the houfe. c Lower curtain which is firft rolled down. d d Upper curtains which are afterwards let down, and which overlay the others — without the afliftance of rings, hooks, &c. as in the firft kind. e End curtain which is rolled outwards, & c. f Rack pullies for letting dowui or rolling up the curtains— fixed only at one end of each walk g Level I I C 225 ) Fig, n. Shews the manner in which the cord is paffecL round the pully on the end of the roller , and the rack fully upon the wall. This kind of curtain ought to roll down from above as fhewn at e , fig. 3 ; and not from below, as in this figure. If from the defcription in Chap. VI. Se£h 1 . and thefe two figures, this mode of fixing the inner roofing fhould appear intricate, which it may do to fome who are not ac- quainted with thefe things, the author can only refer to the model, which none can be at a lofs to underftand. Fig. hi. Se&ion of a vinery fuppofed to be built according to the propofcd plan. — A vinery of this kind is at prefent con/lrucling at Smith’s , Efq: Leith Walk , under the author's direction. A The front flue, made broad and fhallow, fuited to this fituation. Ff b The \ ( 226 ) B The back flue deep and narrow agreeable to its fltuation. c Partition feen in this flue. d Dotted lines fhewing where the air bellows is placed. e End of the curtain. /’Rack pully. g End of the rod of wood which is attached to the curtain. h Wire upon which it Aides down. 1 Trellis on which the vines are trained. k k Upright rods of wood or iron, each being one inch broad, and f of an inch thick, to fupport the wire trellis, and the wire upon which the curtain Aides ; thefe rods are fix- ed to a ftone or board at bottom, and join- ed together at the top. They are alfo fixed to the rafters at the top, but this only be- twixt each curtain, for otherways thefe fixtures would interrupt the rolling down of the curtain. In this way they only in- terrupt the hooking on the overlay which , ( 227 ) can be prevented by making a flit in it, oppodte to the fixture. I A final! piece of iron under each rafter which ferves to fix the trellis and wires to the back wall. m Upright rafter, placed upon the front parapet. n The doping rafters, o Mode of coping by lead and date, by which are joined the roofs of the hot- houfe and backfhed, approven of by the author, as more ornamental and durable. p Water fpout continued along the front of the ouie. q Dotted lines in the back wall, (hewing how the chimney is carried up. Ff 2 PLATE ( 225 ) PLATE V. THrs PLATE AND PLATE VI. CONTAINS PLANS AND SECTIONS OF A PINE STOVE UPON A NEW PRINCIPLE, Fig. i. The ground or foundation plan of the ‘walls and fues. A Back wall. B Front wall, C End walls. D Flues. E Back fhed. a Furnace. c Termination of the fide vacuity. h Termination of the top vacuity or air-flue. Fig, &.1T. * V I ( 229 ) Fig. ii. Surface plan fuppofing the houfe cut over by the line a....b , in plate VI. fig. 2. A and B Two pine pits. a...b PafTage through the centre of the houfe. D A vine introduced from behind intended to cover the back wail. Vines may alfo be introduced at the two front corners to run up the fafhes. g g Air or fleam tubes. K K Regifters or valves for admitting heated air either from the air-flue, or from the large vacuity under the pit, or for pouring in water to cover the furface of the whole pit, or to cover the furface of the air-flue, and thus to produce either fleam or moift heat in abundance. f The fltuation of holes made in the para- pets for pouring in water to the ruble ftone vacuity under the bed of earth, fee fig. 2 . plate VI.. / ( 2 3 0 ) PLATE VI. Fig. i. Longitudinal Section of Figures i and 2 in Plate V. according to the line a....b , fig. 2. a Doors at the ends, h Smoke-flue. c Supports of ditto. d Supports of pafiage-pavement. e The communication of the air-flue with the regifters, K K , in fig. 2. plate V. / Holes A. F. «/ jLcrMtvn- J3f7 jFJZt ////> , fk/tZ/P ■ ( 231 ) f Holes in the wall of the pit for pouring in water, 8tc. g End walls. h h Ground level. Fig. ii. Tranfverfe Section of fig. 2 . plate V. upon a larger jeale. A Pafiage through the houfe. B Ruble hone vacuity. C Earth in which the plants are inferted, either in pots or otherwife. D Air and fleam tubes. E Curtain of the inner roofing. F Rack-pully for ditto. Here alfo may be fixed the hooks for faftening the cords ufed to pull up or let down the glafs fafhes. F Back filed. O A ( n 2 ) G A fpace which may be made an excellent Mufhrom-bed. H Vacuities around the flues. I Air-flue. K Smoke-flue. L A row of bricks to preferve water over the whole furface of this chamber, when it is poured in for the purpofe of creating moift heat, &c. M Dotted lines fhewing the direction of the fhaft or chimney. N Dotted line fhewing the manner inVhich the damper is placed. 0 The author’s mode of coping and roofing hothoufes and backfheds. P Spout for colle&ing water from the roof. Ground level. Fig. iii. Is a feCtion of a fmall mafs of mafon work, containing a circular hole in the centre ( 2 33 ) centre, which hole contains two pipes or tubes, one within another. The inner one is for concluding hot air, and the outer cool air, and the fpace without the outer one is to preferve air ftagnated, in order that as little heat as pollible may be loft. See a full ex- planation, Chap. XI. Sed. 2. page 150. Fig. iv. Is a perfpedive view of the carron regif- ter or valve for regulating the heated air from the flue, which may be had at the Edinburgh Foundry, Edinburgh, or at Mr Dalziel’s, Cabinet-Maker, Chapel-Street, Bedford-Row, Lpndon, along with the fur- nace, afh-pit door, and damper. G g PLATE ( 2 3 4 ) PLATE VII. PLAN AND SECTIONS OF A PIT UPON A NEW CONSTRUCTION. Fig. i. Ground Plan. a Front wall. b Back wall. c Flues. d Supports of the pavement, above which is placed the ruble Jione , and then the earth , &c. e Furnace. f Steps Fn. a. Dr/ ( 235 ) f Steps to the excavation in which the fur- nace is contained. g g Chimneys. h h Dotted lines ihewing the fituation of the fmoke-flue. Fig. ii. Horizontal SeElion , or furface plan of this pit , Juppofing it ereEted and cut over by the line a~~b, fig. 4- A B C D The four divifions which may be kept of four different temperatures. e e Air and fleam tubes. f Air regifters. g Covers of the excavation for the fuel and furnace, &c. partly cut over. Fig. ( 236 ) Fig. hi. Elevation of the Back wall , A Furnace and afh-pit doors. B B Chimneys. C Walk round the back wall of the pit. D Holes for pouring in water, or admitting frefh air to the ruble hone vacuity. Fig. iv. Tranfverfe Section of this Pit. A Earth in which the plants are placed. B Partition in the fmoke-flue. C Pit for fuel, &c. B Supports, made in this particular form, in order to admit the free circulation of the heated air, and to fave bricks in building. Fig. ( 237 ) Fig. v. Longitudinal SeSlion* Range of fafhes. C Spaces betwixt the fupports of the pave- ment. D D Flues. E Centre divifion wall. JF F Tubes which admit air and fleam from the ruble done vacuity. G A tube which admits air and fleam from the large vacuity under the ruble ffone ? which furrounds the flues. Fig. vi. Shews the Mode of fixing the wires for the inner roofing . Fig. ( 23B ) Fig. vii. A Curtain fuitable for a Pit of this ConJiruElion. a a The two poles, one of which are placed at each end. h b The fmall rods for ftretching out the curtain when let down. PLATE Fx. 7T. r • Sr?V'Zr>;//y// tTfcY/b// > /'iy,.<5.fJsr/' a Y YYs-a. V. y^M7 7 ® 07 tSly .'3. J£Yzi Yf///7/ r/* YBerrY nv/YY r/ Y r ■fZourfb/i Z)s/ J? Zam6 Jru/p. ■ \ 6 C 239 ) PLATE VIII. GROUND AND SURFACE PLAN FOR A PEACH- HOUSE, UPON A NEW CONSTRUCTION. Fig. 1. Ground Flan. a a Foundation of the furrounding wall$. b b Flues. c c Termination of the fide vacuity. d d Partitions in the fmoke-flue. e e Supports for the columns, which co- lumns are better ieen in fig. 2. f f Termination ( 2 4 ° ) f f Tennination of the fmoke-flue, where it afeends the centre column as a fhaft or chimney. g Furnace, and pit for fuel, Idc, Fig. ii. Surface Flan, or Horizontal Section. a Columns which fupport the roof. b The column which ferves as a fhaft or chimney. c c Top of the flue which ferves as a paflage around the houfe, d Doors. e Section of the upright rafters, placed on the front walls. f Small holes to admit the heat from the vacuity betwixt the front flue and wall. g Dotts, fhewing the end of the wires upon which the inner roofing Aides down. b h Cover of the furnace, fuel, pit, i$c. PLATE Pl. m. JLoutWt Vti: I'.Za/ub Sculp . ( 241 ) PLATE IX. Fig. i. Longitudinal Section of the improved peach* hoiife , which may be eafily underfiood by comparing it zvith the line a....h , in figures i and 2 , Plate VIII. Fig. ii. Tranfiverje Section of the improved peach - houfe, upon a larger fcale than the ground plan. See c....d, of figures i and 2, Plate VIII Hh a A ( 242 ) a A part of the column which ferves both for a chimney and prop to the roof. b The damper in this column formed in a manner fuitable to the internal aperture, which is circular. It is contrived fo as to be turned round by the handle feen at b ; in place of drawing it out in the ufual manner. e The furnace, around which will be feen the air vacuities, the fmoke-flue, and afh-pit, %£c. d Furnace and fuel-pit, which are covered from the view by the cover, which is fuppofed to be level with the furface of the ground, and painted green. e Supports of the flue, made of confider- able depth, in order to allow the roots of the trees to fpread in every dire&ion, which they could not do, if a mafs of mafon work were introduced below the flues and front wall. f View ( 243 ) / View of one of thofe fupports. g Surrounding walls, built no higher than the furface ol the ground. The line acrofs the wall at g , (hews the depth of thefe fupports. Some may think it advifeable to have the level of the ground, within the peach- houfe, raifed as high as that of the open air, in order that the roots may more eafily penetrate from the one to the other; but this makes no material difference. h Upright glafs raifed upon thofe walls. Fig. hi. Section of both the Plan and Elevation of the improved peach-houfe , fuppofing it finifhed and the trees and vines full grown. In this fe&ion it will be obferved that the inner roofing is made according to the mode H h 2 (hewn ( 244 ) fhewn in plate III. which will have the belt effect in a double roofed houfe. Fig. iv. and v. Are Sections of the approved mode of planting the peaches , and alfo of introducing vines in peach-houfes. See pages 196 — 7. Fig. vi. Is a view of one of the flue , or front wall ) 'up- ports , fuppofed to he made of a Jingle Jl one. Fig. vii. A view of one of thefe fupports formed of bricks , in fuch a way as that the roots of the trees may pafs through it in every direc- tion. N. B. The explanations of the models are feparately printed, and are had along with them, and included in their price. POST. a. ix. ( 245 ) POSTSCRIPT. This work was begun in February la ft, and the author, in order that gentlemen might have an opportunity of altering their hothoufes before the general forcing feafon, , had agreed with the printer and engraver that they fliould execute their departments in a fortnight or three weeks. A promile which very unfortunately they have been unable to perform. Juft when the author had begun the work, he was called to the weft of Scotland, and in order to fupply the prefs with copy, he was under the neceftity of making the (ketches, and writing great part of the account in the inns where he occaftonally flopped ; ( 246 ) Hopped ; and of fending off the manufcri.pt in detached portions to the printer. This accounts for the hurried and carelefs man- ner in which the whole is written; and alfo for a number of typographical errors which the author regrets exceedingly — Some of thefe which materially affed the fenfe are noticed in the errata ; but others, fuch as thofe in page 129, lines 5 and 6, page 163, line 15; page 158, line 8 ; page 186, foot note, &c. occur fo frequently, that nothing can be done but intreat the rea- der’s forgivenefs. Here alfo the author takes an opportuni- ty of mentioning, that though he has Hated in page 122, that the plants in Dickfons’ and Shade’s hothoufe after the improvements were made, “ never fuHained the leqfl da- mage”- — which was true at the time the work was written — yet fome weeks ago, owing to a fmail hole having been made in the imoke-flue, the fmoke entered the houfe, and ( 247 ) and almoft killed two or three of the plants which were neareft the hole. — But this is an accident totally unconnected with the nature or effeCt of the improvements, and therefore cannot injure their utility in the leaft degree. It is only taken notice of here, becaufe fome who are unwilling to approve of the fcheme have endeavoured to report otherwife, and thus to prejudife thofe who have not an opportunity of ex- amining Dickfons’ and Shade’s hothoufe themfelves. The author refts fatisfied, how- ever, that nothing of this kind will affedt the mind of any candid reader. The plants in- jured were completely recovered in a few days, and continue in perfect health and luxuriance. The following particulars defer ve alfo to be taken notice of in this place. I. The author has ere&ed a vinery ac- I i cordinsr O ( 248 ) cording to this plan, at Smith’s, Efq. Leith- Walk In this cafe, it was neceffary to build the furnace in one end of the houfe, to preferve both it, and part of the flue, under the ground level, and alfo to make the flue of the broad low kind, as fliewn in flg. 3. plate II. — to render this as clear as poflible, models are alfo made, which gen- tlemen may have recourfe to, Ihould they find any difficulty in making theff work- men comprehend the principle of thefe fureaces, which is neceffary in fome degree fo as they may be able to vary them agree- ably to different fituations. 2. The author has alfo ufed his improved, furnace , in the cafe of a hotwall at Mr Smith’s, which he thinks will be a very beneficial improvement. The vacuity as in the cafe of hothoufes, is carried round the furnace, but in place of entering an air- flue ( 2 49 ) flue at the throat of the fmoke-fiue, it there enters the fmoke-flue itfelf, and thus the heated air is carried along with the fmoke, and like it gives out its heat to the walls. 3. At Col. Duncan’s, Glenfuir, near Falkirk, he has alfo ere&ed a pit according to his new plan, which is anfwering the purpofe of growing cucumbers excellently. From this cafe, and other circumftances, the author is induced to think, that this kind of pit will be a great benefit to gentle- men, by faving time, rijk, and dung. The faving of dung, he thinks, will be of great advantage, in two ways. 1 ft , Becaufe it is well known among far- mers, that dung, when kept fo long as to be rotted into a folid black mafs, (like old peat,) as is always the cafe with that ufed in hotbeds, cannot be applied to the foil, with half fo much advantage as when in an earlier flage of putrefcency. 2dh, The C 25° ) 2 dly, The dung faved from hotbeds, in 'places where peat mofs abounds, (and there are few places where it cannot be come at,) if formed into compofts as diredted by Lord Meadowbank, * would produce three times the quantity of manure, the firft feafon in which the pits were adopted. This large increafe of manure would pro- duce the means of decompohng a greater proportion of peat mofs than formerly. In this ratio might the improvement go on, and the confequences w~ould be of very great advantage to many gentlemen far- mers ; and it is prefumed, in fome degree to the public in general. That pits upon this principle may be clearly underflood, either for the purpofe of erecting larger or fmaller ones, the author has caufed to be made a model of the one delinated in plate VII. which clearly fhews the * See the Highland Society’s tranfadtions. ( 251 ) the flues, ruble flone vacuity, fleam and air tubes, &c. and alfo the form of curtains, and the mode of placing them fuitable for pits or hotbeds. Owing to the additional trouble and nicety in forming this model, it became neceflary to charge a higher price for it than for the others. Thefe models are fully deferibed in the letter prefs explanations which accompany them. ( I E“ ) : ' • ■ ' * ■ £ 7 : ’ : z.'i a:i I 1 ;'.;/.:., siJ rn ; 1 • ’ iku t : : . b "■ 1- J \ r l ■ ; yj ; •. : I , £9 b I : • rb LoCh: \ji.Pi £•":• ■ r v. - ■ ■ ■<’. / - • ibib'V ■ : : r , r \ APPENDIX DESCRIPTION OP TH IB MODELS OF (THE FURNACE, FLUES, INNER ROOFING, AND NEW PIT, SOLD BY Dicksons and Shade, Edinburgh; and Mr Dalziel, 4 Chapel-Street, Bedford-Row, London, v. ■. r.' ; ; : s .r. ~