UC-NRLF 
 
 SflO 177 
 
 M A N I; A L 
 
 K .X r ) - S ) \ ; E S 
 
GIFT OF 
 Harry East Miller 
 
MANUAL OF EXPLOSIVES 
 
 A BRIEF GUIDE FOR THE USE OF 
 MINERS AND QUARRYMEN 
 
 BY COURTENAY DE KALB 
 
 Professor of Mining- and Metallurgy in the School 
 of Mining* Kingston Ontario 
 
 ISSUED BY 
 
 THE ONTARIO BUREAU OF MINES 
 TORONTO 1900 
 
06 
 
 GIFT OF 
 
ANNOUNCEMENT. 
 
 The growth of the mining industry in Ontario, and the 
 number of casualties which have occurred owing to the 
 careless or ignorant use of explosives employed in the in- 
 dustry, have suggested the need of a book of instructions 
 on the safest methods of handling the materials, both in 
 transportation and at the mines. It is also desirable, 
 where men have not-acqui'ed experience, that hints should 
 be given on the best means of using explosives to obtain 
 the largest economic results. Safety and efficiency are the 
 two chief objects aimed at in the Manual which Prof. 
 De Kalb has been authorized by the Commissioner of 
 Crown Lands to prepare. His own experience in practical 
 mining, his training as a mining engineer, and his know- 
 ledge of the conditions which exist in Ontario acquired in 
 the inspection of mines, have commended him for the task 
 of writing on the subject of explosives, and it is hoped 
 that the Manual will serve a useful purpose. It is 
 issued by the Bureau of Mines for presentation to all mine 
 managers in the Province, as well as to foremen and 
 others who have charge of operations with explosive 
 materials. 
 
 ARCHIBALD BLUE. 
 
 BUREAU OF MINES, 
 
 TORONTO June, 1900. 
 
 M818S9 
 
LETTER OF TRANSMITTAL. 
 
 Mr. ARCHIBALD BLUE, 
 
 Director of the Bureau oj Mines, 
 
 Toronto, Ontario. 
 DEAR SIR : 
 
 In compliance with your in = tractions I have prepared, 
 a/id beg to submit, the following pages on the nature and 
 proper methods of handling of explosives. The matter 
 herein presented is in part a compilation from the litera- 
 ture on explosives, and in part the result of direct inquiry 
 from well known authorities on the subject. To a certain 
 extent I have drawn from my own experience in the 
 practical use and testing of explosives. 
 I have the honor to be, 
 
 Your obedient servant, 
 
 COURTENAY DE KA.LB. 
 
 SCHOOL OF MINING, 
 
 KINGSTON, May 15, 1900. 
 
 5] 
 
TABLE OF CONTENTS. 
 
 PAGE 
 
 PREFACE - 9-10 
 
 CHAPTER I COMMON EXPLOSIVES. 
 
 Classifications Explosive Mixtures of the Nitrate Class : Gunpowder, 
 Blasting Powder, Carbo-azotine, Pyrolithe ; Properties of Gun- 
 powder Explosive Mixtures of the Chlorate Class : Asphaline ; 
 Dangerous character of such Explosives Explosive Compounds of 
 the Nitro-Substitution Class: Borlinetto's Powder, Bellite, Joveite, 
 Securite, Volney Powders, Ammonites, Emmensite, Gelbite, 
 Roburite Explosive Compounds of the Nitric Derivative Class : 
 Guncotton, Nitroglycerine, Properties of Nitroglycerine, Blast- 
 ing Powders made from Guncotton and Nitroglycerine, Tonite, 
 Potentite, Dynamites, Dynamite dopes, Carbodynamite, Judson 
 R. R. P. Powder, Vulcanite, Stonite, Atlas Powder, Giant Powder, 
 Rendrock, Carbonite, Dualin, Horsley Powder, Vigorite, Hercules 
 Powder, Characteristics of Dynamites, Castellanos Powder, Blast- 
 ing Gelatine, Gelatine Dynamite, Gelignite, Forcite Explosives of 
 the Sprengel Class; Rack-a-rock, Hellhoffite Fulminates, Amides, 
 etc. ; Mercury Fulminate, lodoamide 11-41 
 
 CHAPTER II FUSE, CAPS AND METHODS OF FIRING. 
 
 Safety Fuses Quick Burning Fuses Detonators or Exploders Firing: 
 Attaching Fuse to Caps ; Primers ; Batteries ; Connecting and Lead- 
 ing Wires 42-51 
 
 CHAPTER III THEORY OF EXPLOSIVES AND FUMES. 
 
 Explosive Reactions, two Types Detonation and Explosion Products 
 
 of Combustion Physiological Effect of Fumes , . , . 52-05 
 
 17] 
 
8 TABLE OF CONTENTS. 
 
 CHAPTER IV TRANSPORTATION, STORAGE AND 
 HANDLING. 
 
 PAGE 
 
 Transportation in Wagons Ontario and Dominion Laws British Regu- 
 lationsTransportation on Railroads ; Pennsylvania Railroad 
 Regulations Storage in caves, tunnels, etc. ; properly constructed 
 Magazines ; Location of Magazines ; Danger Radius : Lightning ; 
 Care of Explosives Thawing Dynamites 60-89 
 
 CHAPTER V.- BLASTING. 
 
 General Considerations -Line of Least Resistance Forces to be Over- 
 comeCalculating Charges Simultaneous Firing Loading Holes 
 Tamping Mis-Fires Adaptation of Explosives to kind of Work 
 to be done Chambering Bank Blasting Locating Bore-holes 
 Consumption of Explosives Deep Bore-holes 90-110 
 
 APPENDIX A EXAMPLES OF CAUSES OF ACCIDENTS 111-115 
 
 APPENDIX B IMPORTANT BOOKS ON EXPLOSIVES 115-116 
 
 APPENDIX C- -REGULATIONS FOR THE STORAGE AND HANDL- 
 ING OF EXPLOSIVES IN ONTARIO. . . . . .116-118 
 
PREFACE. 
 
 In spite of the enormous quantities of explosives which 
 are consumed in modern engineering operations, there 
 exists a very imperfect knowledge of their character and 
 qualities on the part of the general public. Not only does 
 this entail great risk to life and proper -y from the incau- 
 tious use of these powerful agents of destruction, but 
 their employment by men ignorant of their proper appli- 
 cation for the performance of specific work under varying 
 conditions leads to important waste of material. If a 
 charge of dynamite or other high explosive is so fired as 
 to produce only 75 per cent, of its possible useful effect, 
 there has resulted both a loss of available energy and a 
 waste of a certain portion of the time, labor and power 
 expended in preparing for the blast. The aggregate un- 
 productive expenditure appears as a first charge against 
 the ore or rock extracted. 
 
 In such a brief survey of the subject as is here contem- 
 plated it will be impossible to lay down rules which will 
 enable one to employ explosives always with safety and 
 to the highest economic advantage, but it may serve to 
 conect many erroneous impressions and to point out the 
 way to a better use of blasting agents. For those who 
 wish to acquire further information on the characteristics 
 of explosives, and the proper application of them in indus- 
 trial work, a list of valuable treatises is given at the end 
 of this Manual. 
 
10 PREFACE. 
 
 The immediate cause of the preparation of this manual 
 has been the alarming increase in the number of fatal 
 accidents with explosives occurring throughout the Pro- 
 vince during recent years. In consequence, particular 
 stress will be laid on precautionary measures to insure 
 greater safety. It would seem almost unnecessary to 
 warn intelligent human beings against the perils of warm- 
 ing dynamite over an open tire, of carrying it in their boot- 
 legs, of throwing pieces of dynamite cartridges into out- 
 of-the-way corners of a mine where they may be discovered 
 with painful results in future ; nor would it seem needful 
 to point out the terrible disaster that may follow from 
 biting a cap on to a fuse. But these and equally reckless 
 practices are of daily occurrence at mines and on rail- 
 roads, entailing risk of life not only to those who them- 
 selves are guilty of such criminal carelessness, but, what 
 is worse , to innocent parties who may chance to fall vic- 
 tims to the consequences of the act. 
 
 Special acknowledgment is due to Dr. Charles E. 
 Munroe of Washington, D.C., for valuable suggestions 
 and generous aid in facilitating the preparation of this 
 little guide, and the author desires furthermore to express 
 his sense of indebtedness to the late Mr. Addison C. 
 Rand of New York for much practical assistance. 
 
CHAPTER I. 
 
 COMMON EXPLOSIVES. 
 
 The explosives in common use in America are very few. 
 Practically the average foreman is acquainted with only 
 two kinds, black powder (gunpowder and blasting pow- 
 der), and some of the ordinary varieties of dynamite on 
 the market. The number of explosive compounds recog- 
 nized in Europe runs high into the hundreds, but for the 
 most part their introduction into American practice has 
 been slow and financially unsuccessful. Many of these 
 possess great merit, and deserve a cordial reception by 
 mine managers and quarrymen. To find such conserva- 
 tism toward improvements in blasting powders on this 
 side of the Atlantic is a little surprising. The only explan- 
 ation would seem to be that dynamite is reasonably safe, 
 is nearly as efficient as the best of th^se new compounds, 
 and is sold at a lower cost than is possible with the most 
 of its competitors. That there are explosives, however, 
 which are superior in point of safety to dynamite, and 
 which will yield better economic results in the long run 
 when intelligently applied, is undeniable. But so much 
 better results can be obtained with our old familiar explo- 
 sives than are generally obtained to-day, that it is chiefly 
 desirable to improve upon our present methods. 
 
 According to the British Explosives Act of 1875, all 
 explosives are divided into seven classes, viz. ; 1, Gun- 
 
12 COMMON EXPLOSIVES. 
 
 powder , 2, Nitrate jMixture ; 3, Nitro-conipound ; 4, 
 Chlorate Mixture ; 5, Fulminate ; 6, Ammunition ; 7, 
 Fireworks. 
 
 * This is largely arbitrary, and while serviceable for ad- 
 ministrative purposes is not scientifically exact Among 
 manufacturers of explosives the following classes are gen- 
 erally recognized ; 1, Explosive Mixtures of the Nitrate 
 class ; 2, Explosive Mixtures of the Chlorate class ; 3, 
 Explosive Compounds of the Nitro-substitution class ; 4, 
 Explosive Compounds of the Nitric derivative class ; 5, Ex- 
 plosives of the Sprengel class ; 6, Fulminates and Amides. 
 
 1. EXPLOSIVE MIXTURES OF THE NITRATE CLASS. 
 
 The best known example of this class is gunpowder. 
 The characteristic of these explosives is that they consist 
 of a mechanical mixture of nitrates with some base con- 
 taining charcoal or other substance yielding carbon. The 
 nitrates carry the oxygen which combines with the base 
 under favorable circumstances, developing a large volume 
 of gases at a high temperature, so that if the powder is 
 confined at the time of explosion there will be produced 
 an enormous expansive effort. 
 
 The standard composition of gunpowder is 
 
 Potassium nitrate (nitre or sa'tpetre) 75 parts. 
 
 Charcoal 15 " 
 
 Sulphur 10 " 
 
 100 
 
 The charcoal employed for military and sporting powder 
 is made commonly from dogwood, while for blasting 
 powder willow and alder are used. In some inferior 
 
COMMON EXPLOSIVES. 13 
 
 powders lampblack is substituted in part for charcoal, and 
 in a few brands of special powders lignite, coal and vari- 
 ous forms of carbohydrates are employed. In one inter- 
 esting military explosive, viz., cocoa powder, the carbo- 
 naceous residue remaining after extracting the soluble 
 matter from rye straw with superheated steam is used 
 instead of ordinary charcoal. 
 
 Nitre is generally superior to other nitrates, mainly on 
 account of its failure to deliquesce, that is, to take up 
 moisture from the atmosphere. In this respect barium 
 nitrate is superior, but its cost is high, and the resultant 
 powder is too slow in its action for ordinary purposes. 
 Sodium nitrate is exceedingly deliquescent, and yields a 
 powder which tends to deteriorate rapidly under the 
 influence of moisture. It is never introduced into any 
 but blasting powders, and those containing it should be 
 used while the powder is as fresh as possible, and they 
 should be protected from dampness with great care. It 
 is claimed for them that their action is more powerful for 
 a given weight, on account of the larger amount of avail- 
 able oxygen in sodium nitrate than in an'equal weight of 
 potassium nitrate (nitre). Other forms of blasting powders 
 which have been put on the market at various times may 
 be represented by the following: Carbo-azotine, containing 
 
 Potassium nitrate 70 
 
 Sulphur 12 
 
 Lampblack : 5 
 
 Sawdust 13 
 
 Ferrous sulphate 2 
 
 And Pyrolithe, claimed to produce no carbon monoxide 
 
14 COMMON EXPLOSIVES. 
 
 during explosion, which, if true, should cause the devel- 
 opment of greater power. This contains 
 
 Potassium nitrate 51 . 50 
 
 Sodium nitrate 16.00 
 
 Sulphur 20.00 
 
 Sawdust 11 .00 
 
 Charcoal 1 . 50 
 
 Properties of Gunpowder. The proper color of good 
 gunpowder or blasting powder is a uniform dark gray or 
 slaty hue. A dead black or decidedly bluish color indi- 
 cates either the presence of too much charcoal or an 
 excess of moisture. It should show no difference in color 
 when crushed, and no sharp or angular fragments should 
 be visible before crushing. On pressing the powder between 
 the fingers it should not crack'e, nor should it crush easily by 
 such pressure. It should not crumble under this test, but 
 fall to pieces in angular fragments. The size of grains should 
 be quite uniform, and there should be no dust when new. 
 It should leave no color when poured over the hand or a 
 sheet of paper, which would indicate the existence of meal 
 powder or too mnch moisture. Single bright spots, or 
 bluish-white spots, show that the powder has been damp, 
 causing efflorescence of the saltpetre, which destroys the 
 uniformity of composition of the explosive and renders 
 its action unreliable. As a rule powder has not suffered 
 materially from dampness if no efflorescence of saltpetre 
 has taken place. Damp powder can be restored by drying 
 it in the sun, or in a well ventilated room. 
 
 Good gunpowder should have a specific gravity some- 
 where between- 1.5 and 1.85. The value of the powder, 
 
COMMON EXPLOSIVES. 15 
 
 other things being equal, varies with its specific gravity; 
 the denser it is the more powerful. No simple test, how- 
 ever, as to this property can be made by the ordinary 
 consumer of blasting powder. 
 
 A blow of copper on wood rarelv explodes gunpowder, 
 a blow of wood on wood never, but a blow of copper or 
 wood on stone has frequently exploded it, especially in 
 ramming it into holes with wooden rammers, when the 
 rammer was struck too violently by a hammer. The 
 ignition temperature of blasting powder is 518 F., and 
 of rifle powder 528.8 F. The finest grades of sporting 
 powder ignite at about 600 F. Burning bodies only 
 ignite gunpowder when they are very hot This is well 
 shown in attempting to ignite blasting powder with a 
 match. As long as there is an ordinary flame the powder 
 will not ignite, but as soon as a narrow poin'ed flame 
 issues it ignites instantly. A gas flame will only ignite 
 powder after it has acted upon it fora few seconds. 1 
 Sparks from steel or stone ignite powder easily. An elec- 
 tric spark ignites powder only when the discharge is 
 delayed by the interposition of a bad conductor. An elec 
 trie current will explode gunpowder only through the 
 heating of a resistance wire in the circuit. Good black 
 powder ignited on a piece of white paper burns away 
 rapidly, leaving no residue. If black spots be found they 
 indicate excess of charcoal, or imperfect mixture of the 
 ingredients of the powder. Yellow spots remaining on 
 the paper indicate excess of sulphur ; and if any holes 
 
 1. Oscar Guttmann, " The Manufacture of Explosives," vol. i. p. 332. 
 
16 COMMON EXPLOSIVES. 
 
 have been burned in the paper it indicates excess of 
 moisture, or some other imperfection in the powder. 
 
 2. EXPLOSIVE MIXTURES OF THE CHLORATE CLASS. 
 
 In explosives of this class the oxygen for combustion is 
 present in the well-known compound, chlorate of potash. 
 A mixture of this salt with almost any carbonaceous ma- 
 terial will explode under suitable, and often unexpected, 
 circumstances. The tendency of chlorate mixtures to ex- 
 plode under slight friction, or even without any 
 apparent cause, is so great that they have not come 
 into general use except in fuse compositions and in deton- 
 ators. Almost none of the patented explosives of this 
 class have stood the test of the British Inspectors, only 
 three such explosives having been accepted, and only one 
 of these, asphaline, having been licensed. It consists of 
 thoroughly cleansed wheat or barley bran impregnated 
 with potassium chlorate, mixed with potassium nitrate 
 and sulphate. The proportions of these ingredients are 
 stated to be : 
 
 Potassium chlorate ; 54 parts 
 
 Bran... 42 " 
 
 Potassium nitrate \ 4 " 
 
 Potassium sulphate ' 
 
 The chlorate mixtures will not concern the miner or 
 contractor, and they may be dismissed with a quotation 
 from Dr. Dupre, F.R.S., who says : 
 
 4 * Chlorate of potassium, on account of the readiness 
 with which it lends itself to the production of powerful 
 explosives, offers a great temptation to inventors of new 
 
COMMON EXPLOSIVES. 17 
 
 explosives, and many attempts have been made to put it 
 to practical use, but so far with very limited success. 
 This is chiefly owing to two causes. In the first place 
 potassium chlorate is a very unstable compound, and is 
 liable to suffer decomposition under a variety of circum- 
 stances, and under comparatively slight causes, chemical 
 and mechanical. All chlorate mixtures are liable to what 
 is termed spontaneous ignition, or explosion, in the pres- 
 ence of a variety of materials, more particularly of such as 
 are acid, or are liable to generate acid ; and all chlorate 
 mixtures are readily exploded by percussion, such as a 
 glancing blow which might easily and would often occur 
 in charging a hole. In the second place there is some 
 evidence to show that the sensitiveness to percussion and 
 friction increases by keeping, more especially if the 
 explosive is exposed to the action of moist and dry air 
 alternately." 
 
 Its extreme sensitiveness may be illustrated by the cir- 
 cumstance that chlorate of potash tablets for the throat 
 have been exploded with great violence by replacing a 
 watch into a vest pocket containing a few of them. 
 
 3. EXPLOSIVE COMPOUNDS OF THE NITRO-SUBSTITUTION 
 CLASS. 
 
 The essential difference between an explosive compound 
 and an explosive mixture is that in the latter a number of 
 separately existing chemical substances capable of react- 
 ing and producing a large volume of gases at a high initial 
 temperature, are intimately mixed by mechanical means, 
 while in the case of explosive compounds we are dealing 
 
18 COMMON EXPLOSIVES. 
 
 with a single chemical substance containing oxygen and 
 other elements capable of uniting therewith to form 
 stable gases at a high temperature. The explosion is 
 accomplished by a dissociation of the elements constitut- 
 ing the compound, and by their recombination into a 
 variety of gaseous compounds. The modern high explo- 
 sives consist of such explosive compounds, either used 
 pure, or mixed with other substances which serve to re- 
 duce tne risk of their accidental explosion, and to so modify 
 their action as to adapt them to the requirements of dif- 
 ferent classes of work. 
 
 The nitro-substitution compounds are formed by l 'nitrat- 
 ing " certain hydrocarbons of the aromatic series, which 
 for the most part are coal tar products. The commonest 
 products which are thus employed are phenols (carbolic 
 acid), benzenes, naphthalenes and toluene. The process 
 of nitration consists in introducing into the molecule of 
 the original hydrocarbon a certain quantity of nitrogen 
 and oxygen, by treating it with nitric acid, thus making a 
 new chemical compound, relatively unstable, and contain- 
 ing the necessary elements to produce fixed gases at high 
 temperature as stated above 
 
 The treatment of "carbolic acid," or phenol with 
 nitric acid yields picric acid, a yellow crystalline com- 
 pound having explosive properties which under favorable 
 circumstances may assume violent proportions. Some of 
 the more recent explosives used for charging shells in 
 warfare, such as lyddite, are nothing more than fused 
 picric acid. A mixture of this substance with sodium 
 
COMMON EXPLOSIVES. 19 
 
 nitrate and potassium chromate, known as Borlinetto's 
 powder, is an extremely sensitive and powerful explosive. 
 It contains 
 
 Picric acid 10 parts 
 
 Sodium nitrate 10 " 
 
 Potassium chromate 8.5 " 
 
 Common potassium carbonate, stirred into a boiling 
 solution of picric acid in water, yields crystals of potassium 
 picrate, one of the most sensitive explosive compounds 
 known. When mixed with potassium chlorate its 
 explosive violence equals that of nitroglycerine, with the 
 disadvantage of being infinitely more unstable and sensi- 
 tive. A large number of explosives have been patented 
 consisting essentially of the nitro-substitution compounds, 
 many of which are unsuitable for economic purposes on 
 account of their high cost and dangerous character, while 
 others are equally remarkable as being among the less 
 expensive high explosives, and unequalled for their extra- 
 ordinary freedom from accidental explosion under the 
 circumstances that ordinarily determine such catastrophes. 
 One of the most remarkable of these is bellite, invented 
 by Carl Lamm of Stockholm, Sweden, consisting of 5 
 parts of ammonium nitrate and 1 part of meta-di-nitro- 
 benzene, melted together, into which potassium nitrate is 
 then stirred. It may be molded into cartridge form, or 
 cooled and granulated, forming a free running powder 
 like gunpowder. As this explosive is not now on the 
 market, its price being prohibitive, it may be best to state 
 its peculiar properties in connection with another explos- 
 ive known as joveite, which it resembles closely, this 
 
20 COMMON EXPLOSIVES. 
 
 latter being manufactured in the United States ami sold 
 at prices competing with dynamite. 
 
 Joveite is made in three grades, having the following 
 compositions : 
 
 No. 1 No. 2 No. 3 
 
 Nitro-naphthalenes 8 per cent. 8 per cent. 6 per cent. 
 
 Nitro-phenols .. 16 " 25 " 30 " 
 
 Nitrate of soda 76 " 67 " 64 " 
 
 Of these grades No. 3 is the quickest and most power- 
 ful, and No. 1 the slowest, being about equivalent to low 
 grade dynamites in power. It presents no danger in its 
 manufacture. It will not explode from friction, shock or 
 pressure,' fire, lightning, or electric sparks. It can only 
 be exploded with detonators (" exploders ") such as are 
 used in exploding dynamite. It undergoes no chemical 
 change from age or from atmospheric influences. It is 
 unaffected by tropical heat, or the extreme cold of winter. 
 It does not freeze, but can be used at all normal temper- 
 atures. Its products of explosion contain no noxious 
 gases, so that it is peculiarly adapted to operations under- 
 ground. Its explosive temperature is 536 F. When 
 ignited in the open it burns vigorously, but does not 
 explode. It has been tested by the ablest explosive 
 experts and has never proven unsafe or unreliable. It 
 would seem to fulfil all the requirements of an ideal 
 explosive. 
 
 Securite is an explosive very similar to bellite, having 
 all its advantages, with the disadvantage of the cost due 
 to the ammonium nitrate used. A variety of securite 
 containing ammonium oxalate is said to be flameless. 
 
COMMON EXPLOSIVES. 21 
 
 A class of these explosives which has had considerable 
 acceptance abroad is Known as the Volney powders, 
 named after the inventor, C. W. Volney. They consist 
 of nitro-naphthalenes mixed with saltpetre and sulphur. 
 The higher the degree of nitration the less of the nitrate 
 mixture is required, and the higher is the breaking power 
 of the explosive. The powders can thus be graded to 
 meet the conditions of blasting in hard, or in soft and 
 fissured rocks. They are very insensitive to friction, or 
 shock, and are no more liable to accidental explosion than 
 gunpowder. Judging from the ingredients used it would 
 not seem that their cost should be prohibitive. 
 
 Ammonites, or Favier explosives, -are well known 
 blasting agents of the nitro-substitution class, which have 
 been extensively used abroad, particularly in France. 
 While the different grades vary considerably in composi- 
 tion, the type of the Favier explosive may be repre- 
 sented by the formula 
 
 Ammonium nitrate 90 per cent. 
 
 Nitro-naphthalene 10 " 
 
 The nitro-napthalene is melted and the ammonium 
 nitrate then incorporated with it. Each of these sub- 
 stances alone is very stable, and absolutely safe. When 
 mixed they will still resist rough usage, and will not even 
 explode with the ordinary detonator, requiring a cap con- 
 taining 1 gramme of fulminate of mercury to effect 
 detonation. 
 
 Other explosives of the same class are emmensite, 
 gelbite and roburite. The latter was the invention of 
 
22 COMMON EXPLOSIVES. 
 
 Dr. Carl Roth, and it is claimed that by intro- 
 ducing chlorine into the . nitro-compound a more 
 powerful explosive was produced, exceeding dynamite in 
 this respect, while producing a rending instead of a shat- 
 tering effect. It consists essentially of nitrate of ammo- 
 nium with thoroughly purified chlorinated di-nitrobenzole. 
 Its invSensitiveness is very marked, it does not freeze, and 
 it is claimed to be practically flameless. It requires a 
 powerful detonator to explode it. Roburite is manufac- 
 tured and extensively used in Great Britain. The nitro- 
 substitution powders which have attained an economic 
 importance have collectively acquired the name of " safety 
 explosives," on account of their peculiar properties, and 
 their industrial application will undoubtedly steadily 
 increase in future. 
 
 4. EXPLOSIVE COMPOUNDS OF THE NITRIC DERIVATIVE 
 
 CLASS. 
 
 The two explosives of the nitric derivative class which 
 are generally known are guncotton and nitroglycerine, 
 with special preparations made from them, such as dyna- 
 mite, blasting gelatine, etc. Chemically considered they 
 are nitric derivatives from alcohols, just as the nitro- 
 substitution explosives were nitric derivatives from tha 
 aromatic series of hydrocarbons. A marked distinction 
 between them is that when the nitro- substitution com- 
 pounds are treated with alkalies nitric acid is not repro- 
 duced, but various nitrogenous substances are formed, and 
 when subjected to the action of reducing agents the result 
 is the formation of amides. By treating nitric derivatives, 
 
COMMON EXPLOSIVES. 23 
 
 however, with reducing agents the original ingredients 
 may be reproduced either wholly or in part, according as 
 the derivative is a nitric ether or a nitric ester. 2 Gun- 
 cotton is the representative of the nitric esters, made by 
 the action of nitric acid on a complex alcohol, while nitro- 
 glycerine is the representative of a nitric ether, produced 
 by the action of nitric acid on a simple alcohol. For a 
 general discussion of the chemistry of these interesting 
 bodies the reader is referred to the works of Guttmann, 
 Walke, Berthelot, Chalon and Yon Romocki. 
 
 Guncotton is made by treating suitably prepared cotton 
 with a mixture of 1 part by weight of nitric acid (1.5 sp. 
 g.) and 3 parts of sulphuric acid (1.85 sp. g.). The 
 immersion lasts 48 hours, the temperature being main- 
 tained at GOT. The cotton is then subjected to a thorough 
 and prolonged washing, after which it is carried through 
 various processes to prepare it for use. The cellulose of 
 the cotton has thus been converted into tri-nitrocellulose. 
 By varying the strength of the acids different degrees of 
 nitration may be obtained. Guncotton is extensively 
 employed for military purposes, but not for blasting. It 
 constitutes however one of the ingredients, of blasting 
 gelatine, and is the chief constituent in most so-called 
 * ' smokeless powders. " 
 
 Properties of Guncotton. Guncotton differs but slightly 
 in appearance from ordinary cotton. It has a harsh feel, 
 and is less flexible than common cotton. It becomes 
 highly electrified when rubbed between the fingers, and 
 
 2 Lectures on Explosives by Willoughby Walke, 1897. 
 
24 COMMON EXPLOSIVES. 
 
 appears luminous when rubbed in the dark. It is entirely 
 insoluble in hot or cold water, but dissolves in a mixture 
 of ether and ammonia. It will rarely take up more than 
 2 per cent, of moisture from the atmosphere. It is insen- 
 sible to pressure, percussion or friction, unless closely 
 confined and firmly compressed. It burns with a flash, 
 but without explosion, if brought into contact with a 
 burning or incandescent body. Wet guncotton will not 
 burn or explode. Its ignition temperature is 360F. 
 Pure guncotton will undergo no spontaneous decomposi- 
 tion, and is the safest explosive known. Although it will 
 not explode when wet, it may be detonated when in this 
 condition by a mercury fulminate detonator with a small 
 initial charge of dry guncotton in contact with it. Under 
 these circumstances it develops its maximum force in a 
 minimum of time. Wet guncotton when detonated produces 
 a more violently disruptive effect than if detonated dry. 
 
 Nitroglycerine is a nitric ether, or specifically a glyeeryl 
 tri -nitrate. Different degrees of nitration yield the 
 mono-, di- and tri-nitroglycerine, respectively, the latter 
 being the nitroglycerine of commerce, having the chemi- 
 cal formula C 8 H 5 O. 3 (NO 2 ) 3 . It is made by treating 
 an exceedingly pure quality of glycerine with a mixture 
 of nitric and sulphuric acids, the proportions commonly 
 adopted being 3 parts of nitric acid, 5 parts of sulphuric 
 acid, and from 1 to 1.15 part of glycerine. The glycerine 
 is added very slowly, and with constant stirring. The 
 agitation of the mixture is now usually accomplished by 
 compressed air. 
 
COMMON EXPLOSIVES. 25 
 
 Properties of Nitroglycerine. When made from the 
 purest ingredients nitroglycerine is an oily-looking fluid, 
 as clear and transparent as water. When freshly made it 
 is whitish and opaque, but on standing it clears. As 
 usually made it has a yellowish tint, but the best makers 
 at the present day turn out a nearly water- white product. 
 The specific gravity of nitroglycerine at ordinary temper- 
 atures is about 1.6, which increases when frozen to 1.735, 
 showing that ib contracts 10-121 of its volume on freezing. 
 Nitroglycerine dissolves in alcohol, ether, methyl alcohol, 
 benzine, etc., but is nearly insoluble in water (about 
 0.003 per cent.). Freshly made opaque nitroglycerine 
 freezes at from 2.2F. to 7.6F., while the transparent 
 or " cleared" product freezes at from 39.2F. to 37.4F. 
 In a frozen state nitroglycerine is less sensitive to shock 
 or concussion than when liquid, but on breaking frozen 
 crystals a peculiar molecular change occurs, from which 
 explosions result. It may be completely evaporated at a 
 temperature of 156F.,and dynamite will lose 10 per cent, 
 of its nitroglycerine if exposed for several days to a tem- 
 perature of 104F. It is claimed to very slowly volatilize 
 at normal temperatures above its freezing point. 3 - Its 
 ignition temperature, or, more properly, firing point, is 
 356F. Exposed to a temperature of 365F. it boils with 
 the evolution of vapors. At 381. 2F. it volatilizes slowly. 
 At 392F. it evaporates rapidly. At 422. 6F. it detonates 
 violently. From this point its behavior changes, passing 
 through temperatures at which it explodes with con- 
 
 3 Dwight Brainerd, General Agent Hamilton Powder Co., Montreal. 
 
26 COMMON EXPLOSIVES. 
 
 stantly lessening violerce until, at a dark cherry red 
 heat, it merely assumes the spheroidal state and fails to 
 explode. This is true for small quantities only. When 
 gradually heated it is certain to explode at 356F. If 
 other nitrous compounds are present, due to faulty gly- 
 cerine or faulty washing, nitroglycerine will explode at 
 lower temperatures. These also start the decomposition 
 of the nitroglycerine itself, and are thus productive of 
 spontaneous explosions. 
 
 Nitroglycerine is rapidly decomposed by yellow am- 
 monium sulphide, and other alkaline sulphides, with the 
 separation of sulphur. It is slowly decomposed by an 
 alcoholic solution of potassium hydrate, by ammonia, car- 
 bonate of soda (sal soda), and other alkaline carbonates, 
 by hydrogen-sodium phosphate, hot water, ferrous chlor- 
 ide and sulphuric acid. All acids cause its decomposi- 
 tion, and traces of acids remaining in it from its manu- 
 facture lead to deterioration; hence the importance of an 
 absolutely acid-free nitroglycerine. Any acidity may be 
 detected by litmus-paper (turning blue litmus paper red). 
 For its safe decomposition by inexperienced persons a 
 strong solution in water of sodium carbonate (sal soda) is 
 best. The decomposition is slow and unattended by 
 danger. Gentle stirring with a wooden paddle will facili- 
 tate the reaction. 
 
 The action of the direct rays of sunlight is known to 
 cause the decomposition of nitroglycerine, and may pro- 
 voke an explosion. When decomposition sets in it usually, 
 but not always, proceeds in a tranquil manner, disengag- 
 
COMMON EXPLOSIVES. 27 
 
 ing nitrous fumes which color the nitroglycerine green, 
 then developing nitrogen and carbon dioxide (carbonic 
 acid) and crystals of oxalic acid. After some months the 
 entire mass is converted into a greenish gelatinous body 
 composed of oxalic acid, water and ammonia. But de- 
 composition is not always so quietly accomplished, 
 especially if the temperature is high, as when heated by 
 the sun. It is not to be trusted. If treated to a tempera- 
 ture of 212 F. for a few hours it decomposes. 
 
 In small quantities nitroglycerine will burn quietly, but 
 with large quantities the heat thus generated will bring 
 the entire mass to the explosion temperature before it has 
 burned away. The critical temperature for nitroglycerine 
 lies between 113 F. and 122 F., and its sensitiveness is 
 greatest just above the freezing point. 
 
 Pure nitroglycerine is not sensitive to friction or moder- 
 ate percussion, except when pinched between metallic 
 surfaces. A quantity of it has been thrown up by means 
 of a rocket to a height of 1000 feet, from which it fell with- 
 out being exploded by the impact. When impure, or in 
 a state of decomposition, however, it is exceedingly 
 sensitive and explodes violently on shock, even when un- 
 confined. The best nitroglycerine when confined is liable 
 to explosion by shock. 
 
 Nitroglycerine taken internally, except in minute medi- 
 cinal doses, behaves as an active poison. 
 
 In its pure state nitroglycerine is but little used to-day 
 for blasting. It is still employed to some extent for large 
 blasts, but its chief use is for " shooting" oil and gas wells 
 
28 COMMON EXPLOSIVES. 
 
 to open up the rock and increase the yield of oil or gas. 
 The nitroglycerine is put into tin shells from three to five 
 inches in diameter and from five to twenty feet in length. 
 A strong detonating cap is placed in the cover of this 
 shell, which is then lowered to the bottom of the well by 
 means of a wire. A perforated iron or lead weight is then 
 strung on the wire, and the torpedo is exploded by allow- 
 ing the weight to run down the wire and strike the cap. 
 
 Blasting Powders made from Guncotton and Nitroglycer- 
 ine. The use of guncotton for blast 'ng in any form is 
 not extensive. One of the best known preparations is 
 tonite, now called cotton powder, made by the Tonite 
 Powder Co. It consists of 
 
 Guncotton 52.5 parts 
 
 Barium nitrate 47.5 parts 
 
 These are thoroughly incorporated, and put up in cart- 
 ridge form in paraffined paper. From its composition it 
 would manifestly be an exceedingly safe explosive to 
 handle, and its power should be very great, but the author 
 possesses no reliable information as to its efficiency. Re- 
 cent patents on cotton powder call for the addition to its 
 composition of charcoal, or meta-di-nitrobenzol, either of 
 which would apparently increase its strength, and perhaps 
 reduce its insensitiveness. The original tonite is said to 
 have required a special detonator, failing to explode with 
 even the treble or quintuple strength caps sold for other 
 high explosives. 
 
COMMON EXPLOSIVES. 29 
 
 Potentite resembles tonite, substituting nitre for the 
 barium nitrate. Its composit : on is 
 
 Guncotton 66.2 parts 
 
 Potassium nitrate 33,8 " 
 
 Dynamite is the most largely used of any blasting ma- 
 terial in the world. It was invented in 1866 by Alfred 
 Nobel. The principle consisted in using an absorbent, 
 commonly called a "dope," which would take up the 
 nitroglycerine and hold it somewhat after the manner of 
 a sponge. A suitable dope shouM possess a cellular struc- 
 ture, so that the nitroglycerine may be subdivided into 
 minute globules, each globule held separately in its own 
 cell, completely isolated from every other. In this con- 
 dition its sensitiveness is greatly reduced, depending of 
 course upon the amount of nitroglycerine absorbed. 
 Dynamites may be classified according to the nature of 
 the absorbent used. The following classification is given 
 by Walke : 
 
 I. Dynamite with an inert base 
 
 (Kieselguhr, Magnesium Carbonate.) 
 
 II. Dynamite with an active base. 
 
 A. Combustible base, (carbodynamite). 
 
 B. Explosive base. 
 
 1. Explosive mixture. 
 
 a. Mixture of the nitrate class. 
 
 b. Mixture of the chlorate class. 
 
 2. Explosive compound. 
 
 a. Nitro- substitution compound. 
 6. Nitric derivative compound. 
 
30 COMMON EXPLOSIVES. 
 
 The original dynamite of Nobel consisted of nitro- 
 glycerine absorbed in kieselguhr, or diatomaceous earth. 
 This material consists of the siliceous remains of micro 
 scopic plants, called infusoria or diatoms. These contain 
 microscopic cells and capillary tubes, within which, when 
 the nitroglycerine is once absorbed, it is tenaciously held. 
 The nitroglycerine is thus cushioned against the effects of 
 sudden shocks, and will normally explode only under the 
 powerful impulse of a detonator. The kieselguhr is 
 cleansed and calcined with great care, and will then take 
 up 75 per cent, of nitroglycerine. According as the per- 
 centage of ni roglycerine is reduced the dynamite becomes 
 less sensitive, and at 40 per cent, it requires a powerful 
 detonator to insure explosion. With 20 per cent, of nitro- 
 glycerine it cannot be exploded. Magnesium carbonate, 
 chough a valuable absorbent, will not hold the nitro- 
 glycerine as effectually as kieselguhr. It is used to some 
 extent as a mixture in other dopes. Kieselguhr dynamite 
 is the typical dynamite, but it is not made in America, 
 since other less expensive dopes are available, which under 
 proper conditions afford an almost equal degree of security. 
 
 Dynamite with a Combustible Base. The only well 
 known dynamite of this class is carbodynamite, which 
 consists of 
 
 Nitroglycerine 88.66 parts. 
 
 Carbon 9.85 " 
 
 Sodium carbonate 1 .49 " 
 
 The carbon is an exceedingly porous variety of charcoal 
 made by carbonizing cork. It does not disintegrate nor 
 " leak " nitroglycerine, but its cost is prohibitive. 
 
COMMON EXPLOSIVES. 31 
 
 Dynamite with an Explosive Base : Nitrate mixture 
 class. The earliest experiments of Nobel to produce 
 what we now know as a dynamite consisted in making 
 cartridges of black powder and pouring nitroglycerine 
 into them. Similar attempts to combine the two explo- 
 sives have often been made, since it was expected that the 
 detonation of the contained nitroglycerine would also 
 cause the detonation of the gunpowder, thereby increas- 
 ing the power of the latter about four-fold. The most 
 highly perfected explosive of this kind is the Judson R.R. 
 P. powder, which consists of a special honey-combed gun- 
 powder, which absorbs 5 per cent, of nitroglycerine and 
 remains a free running powder. 4 It is particularly re- 
 commended for seam blasting. The common Judson 
 powder, which also belongs to this class, contains 
 
 Nitroglycerine 5 parts. 
 
 Sodium nitrate 64 " 
 
 Sulphur 16 " 
 
 Cannel coal 15 " 
 
 Vulcanite resembles this, replacing the cannel coal by 
 charcoal and increasing the amount of nitroglycerine. 
 Its composition is 
 
 Nitroglycerine 30.0 parts. 
 
 Sodium nitrate 52.5 " 
 
 Sulphur 7.0 " 
 
 Charcoal 10.5 " 
 
 Powders of this character mark a radical departure 
 from the original dynamite with an inert base. Attempts 
 were made to find a less expensive but reliable inert dope, 
 
 * Prof. Charles E. Munroe. 
 
32 COMMON EXPLOSIVES 
 
 and later the effort was made to use a nitrate mixture 
 with a certain proportion of an inert substance to limit its 
 sensitiveness. The advantage of so doing is problematical. 
 Sufficient care in preparing the combustible material in 
 the nitrate mixture is undoubtedly of more value than the 
 admixture of any earthy ingredient. As examples of 
 dynamites with nitrate mixture dopes containing mineral 
 deterrents may be cited the following : 
 
 STONITE. 
 
 Nitroglycerine 68 parts. 
 
 Keiselguhr 20 " 
 
 Woodmeal 4 " 
 
 Potassium nitrate 8 " 
 
 ATLAS POWDER. 
 
 Nitroglycerine 75 parts. 
 
 Wood fibre 21 " 
 
 Sodium nitrate 2 " 
 
 Magnesium carbonate 2 " 
 
 GIANT POWDER No. 2. 
 
 Nitroglycerine 40 parts. 
 
 Sodium nitrate 40 " 
 
 Sulphur C " 
 
 Resin (powdered) 8 " 
 
 Kieselguhr 8 " 
 
 There is no objection to be urged against the use of a 
 small quantity of inert substance in the dope, but it is 
 not necessary. The dynamites of commerce in America 
 are probably about equally divided between those with 
 and without such an admixture. As examples of standard 
 dynamites which do not contain this ingredient the fol- 
 lowing are sufficiently representative : 
 
COMMON EXPLOSIVES. 33 
 
 RENDROCK. 
 
 Nitroglycerine 40 parts. 
 
 Potassium nitrate 40 " 
 
 Woodpulp 13 " 
 
 Pitch 7 
 
 CARBONITE. 
 
 Nitroglycerine 25 . parts. 
 
 Woodmeal 40.5 " 
 
 Sodium nitrate .. 34.0 " 
 
 Sodium carbonate 0.5 " 
 
 DUALIN. 
 
 Nitroglycerine 40 parts. 
 
 Sawdust 30 " 
 
 Potassium nitrate 20 " 
 
 Chlorate Mixture Class. The same objection which 
 applied to the chlorate mixture powders may be urged 
 with equal force against dynamites containing potassium 
 chlorate in the dope. Those which have given the best 
 results are the following : 
 
 HORSLEY POWDER. 
 
 Nitroglycerine 72 parts. 
 
 Potassium chlorate 6 " 
 
 Nutgalls 1 " 
 
 Charcoal 1 " 
 
 VlGORITE. 
 
 Nitroglycerine 30 parts. 
 
 Potassium chlorate 49 " 
 
 Potassium nitrate 7 " 
 
 Woodpulp 9 " 
 
 Magnesium carbonate, moisture, etc ....*.... 5 " 
 HERCULES POWDER. 
 
 Nitroglycerine 40.00 parts. 
 
 Potassium nitrate 31.00 " 
 
 Potassium chlorate 3 .34 " 
 
 Magnesium carbonate 10.00 " 
 
 Sugar 15.66 " 
 
34 COMMOr EXPLOSIVES. 
 
 In all the above dopes, where woodpulp or sawdust is 
 employed it should consist of a porous wood, such as 
 basswood or spruce. Woodpulps vary considerably in 
 the amount of nitroglycerine they will absorb, ranging 
 from about 60 per cent, to 85 per cent. Before intro- 
 ducing the nitroglycerine it should be thoroughly dried, 
 on no account being allowed to retain more than 1 per 
 cent, of moisture. Nothing is more certain to cause 
 deterioration of dynamite, with "leaking" of the nitro- 
 glycerine, than moisture, and dynamite so deteriorated is 
 exceedingly dangerous and should not be used. 
 
 Characteristics of Common Dynamites. The character- 
 istics of the ordinary dynamites, which are those having 
 dopes of the nitrate and chlorate mixture class, may be 
 considered before giving an account of the more peculiar 
 combinations of nitroglycerine with nitro- substitution and 
 nitric derivative compounds. There are certain require- 
 ments which all dynamites should fulfil, and it is the duty 
 of all persons using or handling them to see that they do 
 not fall short of the proper standard. Good dynamite 
 should not feel greasy. There should be no trace of free 
 nitroglycerine inside the wrapper of the cartridge. In 
 order to test this point, lay one of the suspected cartridges 
 on a sheet of clearf brown paper in a room at from 60 to 
 80 F. for a period of about 1 2 hours. If the cartridge 
 has begun to "leak" nitroglycerine, this will be shown 
 by an oily discoloration on the brown paper. Dynamite 
 properly made should be proof against leakiness under 
 normal conditions of temperature and moisture. To test 
 
COMMON EXPLOSIVES. 35 
 
 its quality in this respect two separate determinations 
 should be made. First, freeze and thaw samples of the 
 dynamite three successive times, and test for leakiness as 
 explained above. Second, expose samples to a tempera- 
 ture between 85 and 90 F. for six consecutive days and 
 nights, and again test for leakiness. In neither case 
 should any trace of free nitroglycerine be seen on the 
 brown paper. If slowly heated dynamite explodes at 
 356 F., and if rapidly heated it explodes at 446 F. 
 These temperatures apply only to kieselguhr dynamite. 
 The American dynamites, containing woodpulp and 
 nitrates, will explode at somewhat lower temperatures. 
 Like nitroglycerine, it is most sensitive to shock or fric- 
 tion just above its freezing point. According to the 
 character of dope used it freezes at from 42 to 46 F. It 
 is nearly if not quite insensitive to shock when frozen, 
 but not entirely so to friction. Cartridges broken while 
 frozen are liable to explosion from molecular disturbance 
 of the nitroglycerine crystals. Ramming frozen sticks 
 into a hole is attended with the same danger. Ex- 
 plosion of frozen dynamite may be due to long crys- 
 tals of nitroglycerine with films of unfrozen nitro- 
 glycerine, exploded by friction. 5 Frozen dynamite is 
 not incapable of being detonated, especially if very 
 powerful detonators be used. Any efflorescence, 
 whitish film, or incrustation on dynamite cartridges in- 
 dicates either that the dynamite itself contained an excess 
 of moisture in the dope, or (what is most likely to be the 
 
 5 Dwight Brainerd. 
 
36 COMMON EXPLOSIVES. 
 
 cause) that it has been subjected to excess of dampness 
 in transportation or storage. In either case the incrus- 
 tation is due to the dissolving out of the nitrate of soda 
 or potash from the dynamite. This has consequently de- 
 stroyed its homogeneity, and such dynamite is almost 
 always leaky, or will soon become so. It is unreliable, 
 may fail to explode in blasting, and will produce noxious 
 fumes if it does explode. Its power as an explosive has 
 been reduced also, so that it possesses the disadvantages 
 of being dangerous to handle, unreliable as a blasting 
 agent, and at best uneconomical. It should not be used, 
 but should be destroyed. 6 Exposure to the rays of the 
 sun, especially if transmitted through window glass, is 
 liable to produce decomposition and explosion. A strong 
 electric discharge, or a flash of lightning, will usually ex- 
 plode dynamite. Dynamite placed in water gradually 
 parts with its nitroglycerine, its place in the cartridge 
 being taken by the water. Attention is specially drawn 
 to this fact because of the popular impression that dyna- 
 mite is unaffected by water, an error that has probably 
 arisen from the fact that it can be used in wet holes or 
 under water. In wet situations it should be tired within 
 a reasonable time after preparing the charge, and under 
 no circumstances allowed to remain unexploded for a 
 period of many hours ; otherwise nitroglycerine will leak 
 out and find its way into crevices, where it may cause 
 accidents later on. The characteristics given above apply 
 to all those explosives known popularly as dynamite, 
 
 e See Chapter IV. 
 
COMMON EXPLOSIVES. 3? 
 
 giant powder, dualin, atlas powder, hercules powder, 
 rendrock, etc. 
 
 Dynamite with an Explosive Base of the Nitro-substitu- 
 tion class. This species of dynamite is little known in 
 America. Its best representative is Castellanos powder, 
 which contains a picrate, usually picrate of ammonia, in 
 the dope. Its composition is 
 
 Nitroglycerine 40 parts. 
 
 Picrate 10 
 
 Sodium nitrate 25 
 
 Carbon 10 
 
 Sulphur 5 
 
 Some insoluble salt 10 
 
 Dynamite with an Explosive Base of the Nitric Deriva- 
 tive class The representative of this class of explosives 
 is what has been called blasting gelatine. It consists of 
 soluble guncotton dissolved in nitroglycerine by the aid 
 of heat, the result being a tough, jelly-like, translucent, 
 elastic substance, varying in color from bright yellow to 
 yellowish brown. It has a specific gravity of 1.6, does 
 not absorb water, and when placed in it is affected only 
 on the surface, and no further change occurs. Uncon- 
 fined it burns, but does not explode. Heated slowly it 
 explodes at 399 F., and heated rapidly it explodes at 
 464 F. At low temperatures it freezes into a hard solid 
 of crystalline structure. The temperature at which it 
 freezes is somewhat variable, but usually this occurs 
 between 35 and 40 F. It is far more sensitive when 
 frozen than when unfrozen, and can be readily detonated 
 or exploded by the impact of bullets. It is peculiarly 
 
38 COMMON EXPLOSIVES. 
 
 adapted to use in warm climates It will not leak nitro- 
 glycerine, even after repeated freezing and thawing, nor 
 after prolonged exposure to a temperature of 90 F. It 
 is more powerful than ordinary dynamites, and requires a 
 stronger detonator to develop its maximum intensity. 
 
 Gelatine dynamite is an explosive in which the blasting 
 gelatine has been incorporated with a dope to modify its 
 action. The best known gelatine dynamites are the fol- 
 lowing : 
 
 GELIGNITE. 
 
 65 percent, of blasting gelatine r Nitroglycerine 96 r ^ per cent, 
 containing 1 Collodion cotton 3\% " 
 
 35 per cent, of absorbent, con- f Sodium nit ' ate 4 75 V e * cent - 
 J Sodium carbonate 1 " 
 
 on-J 
 
 taining \ Woodpulp 24 
 
 FORCITE. 
 
 50 per cent, of blasting gelatine/ Nitroglycerine 98 per cent, 
 containing \ Collodion cotton 2 
 
 C Sodium nitrate 76 
 
 50 per cent, of absorbents, con- I Sulphur 3 
 
 taining 1 Woodtar 20 
 
 \ Woodpulp 1 
 
 For these explosives a test for stability is of importance. 
 For this purpose repeated freezing and thawing, followed 
 by the test for leakiness, as with ordinary dynamites, and 
 prolonged exposure to a temperature of 90 F., again test- 
 ing for leakiness, are requisite. Any tendency to leak 
 under such circumstances is due to the presence of mois- 
 ture in the ingredients, and the fault lies entirely with 
 the manufacturer, and not with exposure to unsuitable 
 conditions in transportation and storage. It possesses 
 many advantages over common dynamites, and is rapidly 
 supplanting them in most European countries. It is not, 
 
COMMON EXPLOSIVES. 39 
 
 however, as safe a material, being liable to spontaneous 
 explosion, and being entirely untrustworthy in coM wea- 
 ther. Until these disadvantages are overcome it is not a 
 desirable explosive to put into the hands of inexperienced 
 persons. 
 
 5. EXPLOSIVES or THE SPRENGEL CLASS. 
 
 Dr. Hermann Sprengel in 1873 called attention to a 
 new class of explosives whose principle consisted in the 
 admixture, immediately be r ore use, of two ingredients, 
 themselves inexplosive, but producing when mixed a 
 substance capable of violent detonation. The mixing of 
 the ingredients cannot usually with safety be done by 
 unskilled persons, but in the hands of a careful manipula- 
 tor they are of great value. This class of explosive is 
 being extensively employed by the Russian government 
 in Siberia, and where transportation may be attended with 
 danger, or where large supplies may have to be kept for a 
 prolonged period, the Sprengel explosives are peculiarly 
 desirable. The most successful of these has been Rack-a- 
 rock, manufactured by the Rendrock Powder Co. It 
 consists of 
 
 Potassium chlorate 79 parts. 
 
 Mono-nitrobenzene 21 " 
 
 The potassium chlorate is made up into cartridge form, 
 being specially prepared so as to increase its absorptive 
 quality. The liquid mono-nitrobenzene is put up in ves- 
 sels containing the proper proportion to saturate the cart- 
 ridge. The immersion is made about ten minutes before 
 use. It is no more dangerous, perhaps less so, than com- 
 
40 COMMON EXPLOSIVES. 
 
 mon dynamites, though it would develop the untrust- 
 worthy character of all chlorate mixtures if kept. Its 
 specific gravity is 1.7, and it requires a powerful detonator. 
 Liquid explosives of this class have been patented, and 
 have met with some favor abroad, but the difficulties 
 attendant upon the use of a liquid in blasting are so great 
 that it can be employed to advantage only in very special 
 cases. As an example of these may be given 
 HBLLHOFFITE. 
 
 >-. Meta-di-nitrobenzene 47 parts. 
 
 Nitric acid (sp. g. 1.50) 53 " 
 
 A very powerful detonator is required to explode it. Its 
 intensity appears to be greater than nitroglycerine, and it 
 is claimed to resist explosion by a shock or an open flame. 
 
 6. FULMINATES, AMIDES, ETC. 
 
 These are the most powerful and dangerous explosives 
 in common use. They consist for the most part of metallic 
 salts of fulminic and amic acids. The formula H 2 C 2 N 2 O2 
 has been assigned to fulminic acid, though it has never 
 been isolated. The commonest fulminate, known as mer- 
 cury fulminate, is formed by. dissolving mercury in nitric 
 acid, to which solution, when cool, is added 110 parts of 
 alcohol. Water is then added, causing the gray fulminate 
 to precipitate. This is carefully washed and air dried. 
 The operation is attended with great danger. The color 
 of the fulminate varies from white to dirty gray. Its 
 specific gravity is 4.42 ; it has a sweetish taste and is 
 highly poisonous. It is extremely sensitive to heat and 
 
COMMON EXPLOSIVES. 41 
 
 shock of every kind. Its firing point when slowly heated 
 is 305.6 F., and when heated rapidly 368.6 F. It is less 
 sensitive, but not secure against explosion, when wet. 
 The slightest friction will provoke its explosion. It may 
 be destroyed safely by treating it with alkaline sulphides. 7 
 
 Fulminates of other metals are capable of being made, 
 such as fulminates of silver, gold, platinum, zinc and cop- 
 per, but these are more violently explosive, and less stable, 
 than mercury fulminate ; the only one which has come into 
 any use being the silver compound, and this not in indus- 
 trial operations. 
 
 The amides are still more perilous, and are of no econo- 
 mic importance. lodoamide, or nitrogen iodide, is so 
 unstable that it will exolode on bein^ touched with a 
 feather, its destructive effect being very great. These 
 latter compounds are of interest only to the chemist and 
 experimentalist. 
 
 7 See Chapter II. 
 
CHAPTER II 
 
 FUSE, CAPS AND METHODS OF FIRING. 
 
 The explosion of blasting powders is accomplished 
 either by the direct application of a high temperature 
 unaccompanied by a shock, as in the firing of gunpowder 
 by a fuse, or by the application of a very powerful shock 
 in which the high velocity of the explosive wave is of 
 more consequence than the temperature, as in the explo- 
 sion of. dynamites by caps or detonators loaded with 
 fulminating compounds. The detonators may be exploded 
 electrically or by fuse. 
 
 SAFETY FUSES. 
 
 Safety Fuses, also commonly called Bickford Fuses, 
 after William Bickford of Cornwall, who patented them 
 in 1831, consist essentially of a powder thread spun 
 around with jute yarn, and impregnated with composi- 
 tions to make them waterproof. The core of powder 
 being tightly compressed in a thin continuous thread 
 \vithin the fuse, the fire only travels along it slowly, the 
 rate of burning of a good fuse being about 30 seconds per 
 foot. In the Bickford process a number of jute threads 
 pass through an. orifice while they are slowly rotating, a 
 fine current of meal gunpowder being fed into the jute 
 tube thus formed The cord is' kept stretched in a per- 
 pendicular position while being formed around its core of 
 powder. This cord is then sent to another machine, 
 [42] 
 
FUSE, CAPS AND METHODS OF FIRING. 43 
 
 which spins a second layer of jute yarn around it in the 
 opposite direction. The fuse is next drawn through a 
 bath of coal tar, to which a little wo jd-tar has been added. 
 This coats externally and partly penetrates the cord. 
 Subsequently it is drawn through fuller's earth, or china 
 clay, and then cut into lengths. This makes the " single 
 black fuse," which is moderately waterproof. The white 
 fuses are treated with china clay made into a paste with 
 glue size, and red fuses are coated with bolus powder. 
 These are less waterproof than the black fuse. For wet 
 bore-holes " double " and "tape" fuses are employed. 
 The "double" fuses are made like ordinary black fuse, 
 and then rewound with another layer of yarn and again 
 coated with tar and clay. " Tape " fuses are wound with 
 waterproof tape, overlapping. For blasting under water 
 special gutta-percha covered fuse is manufactured. A 
 great variety of fuses are made, differing in the character 
 of the covering put around the original yarn containing 
 the powder core. 
 
 QUICK BURNING AND DETONATING FUSES. 
 In order to accomplish simultaneous firing of a number 
 of holes with fuse instead of by electricity quick-burning 
 fuses are made by coating a wick with meal powder paste, 
 having yarn loosely spun over it. In order to fire a num- 
 ber of shots at once the several fuses, all of equal length, 
 are attached to a sheet iron connector, in one end of 
 which is a disk of powder and a perforated wooden plug 
 for the insertion of an ordinary safety fuse. The quick 
 burning fuse burns at the rate of 500 feet per second. 
 
44 FUSE, CAPS AND METHODS OF FIRING. 
 
 A similar fuse made in Austria contains a quick-burning 
 core consisting of four cotton threads filled with a paste of 
 equal parts of ferrocyanide of lead and potassium chlorate 
 mixed with alcohol. This however, is slower than the 
 Bickford rapid fuse. 
 
 A practically instantaneous fuse is that invented by 
 Col. Philip Hess, which is known as a detonating fuse. 
 In this a cotton thread is saturated with a paste of mer- 
 cury fulminate. The ends of the fuse are subjected in 
 the connector to the action of a detonating cap. The 
 rate of transmission of the explosion through this fuse is 
 16,400 feet per second. 1 
 
 Fuse should be kept perfectly dry, preferably in canis- 
 ters, and care should be taken to keep it out of contact 
 with oils. 
 
 DETONATORS OR EXPLODERS. 
 
 For use with high explosives a detonating cap is essen- 
 tial in order to impart a sufficient initial impulse to 
 develop the full strength of the powder. These differ 
 from caps employed for sporting ammunition in that the 
 heat engendered in exploding the fulminate is employed 
 in the latter to ignite the powder, the quality of the ful- 
 minate used being very small, and it is fired in contact 
 with the powder. In the case of detonators, however, the 
 fulminate is enclosed in a copper capsule, out of contact 
 with the explosive. The detonation of the fulminate 
 pulverizes the end of the capsule, so that the temperature 
 resulting from it is communicated to the explosive, but it 
 
 1 Guttmann, The Manufacture of Explosives, vol. II. p. 300. 
 
FUSE, CAPS AND METHODS OF FIRING. 45 
 
 is the violence of the shock that is relied upon to start 
 the detonation of the high explosive. For this purpose 
 considerably larger quantities of the fulminate of mercury 
 are employed. The ordinary detonator, whether made 
 for firing by fuse or electricity, contains usually 
 
 Mercury fulminate 75 parts 
 
 Potassium chlorate 25 " 
 
 Some manufacturers use potassium nitrate instead of 
 the chlorate. Detonators are graded according to the 
 amount of mercury fulminate in the composition, as 
 follows : 
 
 Single strength 3 grains of mercury fulminate 
 
 Double " 6 " " " 
 
 Treble " 9 " " " 
 
 Quadruple strength 12 " " " 
 
 And so on. The stronger the detonator used the more 
 powerful will be the detonation of the dynamite or other 
 high explosive. The treble strength should be used in 
 ordinary practice, and will prove to be more economical 
 than the lower grades. 
 
 The fulminating composition is compressed in the end 
 of the capsule and then covered with shellac, collodion, 
 celluloid, or thin copper foil or paper, to prevent the com- 
 position from coming out. The end of the capsule above 
 the composition is then left open to receive the fuse. In 
 electric detonators, a piece of resistance wire, usually 
 platinum, is compressed in the composition, the ends be- 
 ing attached to copper wires leading out through a hard 
 plug of sulphur and ground glass which fills the capsule. 
 These wires are wound with cotton insulation. The 
 
46 FUSE, CAPS AND METHODS OF FIRING. 
 
 heating of the short piece of resistance wire to incandes- 
 cence, due to the passage of the electric current, explodes 
 the fulminate. This is the most reliable form of electric 
 detonator, which, however, requires currents of great in- 
 tensity, though of low tension, to generate which power- 
 ful electric machines are required to fire a large number 
 of detonators. Another common form is the slot deton- 
 ator A plug of melted sulphur and powdered glass is 
 molded over a U-shaped piece of brass wire. A fine slot is 
 then cut through the wire at the centre of the bend. The 
 plug is then inserted into the capsule so that the two bent 
 ends of the wire project into the priming mixture of anti- 
 mony sulphide and potassium chlorate, which in this kind 
 of cap is placed on top of the fulminating composition. 
 The bridge detonator is similar to the slot form, except 
 that the terminals are filed off flush with the inside face of 
 the plug, along which a line is drawn from one terminal to 
 the other with a soft black lead pencil, thus forming a 
 path for the current with many points at which sparking 
 takes place. This form of detonator is very sensitive, 
 and great care must be taken in its manipulation and 
 coupling up. 
 
 FIRING. 
 
 In the use of fuse for exploding gunpowder it is only 
 essential to see that the end of the fuse is well buried in 
 the charge. This applies whether the powder is poured 
 loose into a dry hole, or is made up in cartridge form. 
 When made into cartridges the ends of the paper should 
 be securely tied around the fuse, but not so tightly as to 
 
FUSE, CAPS AND METHODS OF FIRING. 47 
 
 constrict it and interrupt the continuity of the powder 
 core. The cartridges may be made by using a long strip of 
 brown paper, folding one end around the end of a cylind 
 rical wooden form, and then spirally winding the paper 
 upon the form,, with the edges well overlapping. Before 
 removing the case thus made from the form it should be 
 dipped into melted paraffine, giving it several coats. If 
 the hole is very wet another wrapping in the reverse direc- 
 tion, with a coating of paraffine, will insure the dry ness of 
 the charge, and after loading and attaching the fuse it 
 may be immersed up to the fuse in the molten paraffine, 
 making sure that it is not appreciably hotter than the 
 melting point of the paraffine, viz., 113F. This will 
 make a perfectly water tight cartridge, but of course 
 cannot be rammed in a hole. 
 
 A detonator is employed only with high explosives. 
 One end of the cartridge paper is opened up and a hole i s 
 made by firm pressure with a hard- wood instrument, with 
 a rounded end, no larger in diameter than the cap to be 
 inserted. The hole should be driven to no greater depth 
 than is suitable for the cap, so that the end of the cap 
 shall reach the bottom of the hole and leave at least J- of 
 an inch of the end of the copper capsule projecting above 
 the end of the cartridge. Otherwise the fuse coming in 
 contact with the dynamite may ignite and explode it be- 
 fore detonation can occur, thus greatly reducing the power 
 of the explosive, and producing deleterious fumes from 
 the imperfect combustion of the powder. The ends of the 
 paper of the cartridge are now drawn closely around the 
 
48 FUSE, CAPS AND METHODS OF FIRING. 
 
 fuse, and tied as before. The cartridge thus prepared is 
 called the "primer." The same method is pursued in 
 placing the eltctric detonator, with the difference that it 
 is not objectionable to bury the cap in the dynamite. 
 This is recommended by G. Gr. Turner as insuring success. 
 Under no circumstances, however, must this be done with 
 caps fired by fuse. It is of the utmost importance, in 
 order to realize the full force of the explosive, that the 
 cap shall fit neatly and accurately in the hole made for it 
 in the dynamite. An air-space, even of a small fraction 
 of an inch below the cap, will serve as a cushion, mask- 
 ing the force of the detonation of the cap, and reducing 
 the initial violence of the explosive wave imparted to the 
 dynamite, upon which directly depends the violence of 
 the explosion which it produces. 
 
 The end of the fuse which is to be inserted into the cap 
 should be cut off square across, preferably with a fuse- 
 cutter such as is supplied by all dealers in explosives, and 
 then holding the fuse vertically with this end up, slip the 
 cap lightly over it. Do not press it on to the fuse, nor 
 turn it on the fuse end, as this may explode the cap by 
 friction. Then crimp the walls of the cap about J inch 
 from its upper end upon the fuse by means of the crimper, 
 which is combined with the fuse-cutter above mentioned. 
 No other instrument should ever be used, and under no 
 circumstances should the cap be bitten upon the fuse. 
 To do so is to run a tremendous risk. Let any one 
 who doubts this explode a cap held against a No. 
 18 iron plate, by fixing the cap in a hole bored in a block 
 
FUSE, CAPS AND METHODS OF FIRING. 
 
 49 
 
 of wood and fixed against the iron. After seeing the hole 
 which an ordinary detonator will make through such a 
 piece of metal, he would be a fool indeed who would again 
 bite so sensitive an explosive agent with his teeth. 
 
 The free end of the fuse should be kept up out of the 
 water, and no two fuses should cross each other. A. slit 
 should be cut a half-inch long in the end to sufficiently 
 expose the core for prompt lighting. It is not good 
 practice to attach wicking or other material soaked in oil 
 to che end of the fuse for igniting it, but dry paper may 
 be twisted upon the end if desired. If properly slit, and 
 turned sideways so as to expose the core without shatter- 
 ing out the powder, the fuse can be readily lighted with a 
 candle flame. 
 
 In firing bj battery the ends of 
 the copper wires attached to the 
 detonator are to be twisted tightly 
 upon the ends of the heavily in- 
 sulated "leading wires." The ends 
 should be bent over, forming a 
 hook, so that the detonator wire 
 . may by no chance become detached. 
 The ends of the wires must be 
 scraped bright, so as to insure ample 
 contact between clean surfaces to 
 carry the electric current. Where 
 more than one hole is to be fired 
 at the same time, connecting wire is employed to connect 
 up the whole series of charges. The method of wiring is 
 
 50:.: 
 
 Fig. 1. 
 
50 FUSE, CAPS AND METHODS OF FIRING. 
 
 shown in the accompanying sketch (Fig. 1) which is 
 assumed to represent a V-cut for the " bearing-in shots " 
 in a tunnel breast. Here the 8 shot-holes indicated con- 
 stitute the "unkeying," or " breaking- in " shots. Of 
 these, Nos. 1, 2, 3 and 4, being shorter than Nos. 5, 6, 7 
 and 8, are fired first ; hence these are connected for one 
 volley. In the figure, L L are the leading wires, 
 D D D etc., the detonator wires, and c c c the connecting 
 wires. The connecting wire is of larger diameter than 
 the detonator wires, but smaller than the leading wires, 
 and less heavily insulated than the latter. Care must be 
 observed not to allow any bare portions of one wire to 
 touch another, nor to come into contact with the damp 
 earth or rock. The leading wires should never be twisted 
 together, nor carried to the working face in contact with 
 each other, or in contact with pipes or other metallic 
 objects, nor should they lie in water. Disregard of these 
 precautions will lead to " short-circuiting," or grounding 
 of the current as soon as the insulation is a little worn, 
 causing either failure to explode the charges at all, or a 
 mis-fire in some of the holes. The hands of the operator 
 while connecting up the wires, and especially when con- 
 necting the leading wires to the battery, should be per- 
 fectly dry. 
 
 FIRING MACHINES. 
 
 It is perfectly feasible to fire charges with battery cells 
 and an induction coil, but such an appliance is not suited 
 for work under the conditions of mining and quarrying 
 operations. Various forms of frictional machines have 
 
FUSE, CAPS AND METHODS OF FIRING. 51 
 
 been designed for blasting purposes, bub they are .sensitive 
 to dampness, and require frequent testing. They are 
 justly becoming obsolete. The standard blasting battery 
 of to-day is a dynamo-electric machine, which is not 
 affected by moderate dampness, and is always ready for 
 use. In these there is an electro-magnet, between the 
 poles of which rotates an armature, developing the current 
 precisely as is done by an ordinary dynamo. The arma- 
 ture is driven by a rack and pinion, the current thus 
 generated being rectified by a commutator. The arma- 
 ture is short-circuited until the rack in descending breaks 
 the short circuit, and the current then passes into the 
 firing circuit through the terminals or binding posts to 
 which the leading wires are attached on the outside of the 
 machine. Machines operated by a crank are more liable 
 to accidents from a premature discharge than the so-called 
 " pull-up" batteries, worked by the rack and pinion. A 
 machine is rated at the full number of detonators which 
 it will fire under favorable conditions. To insure freedom 
 from mis-fires, it should never be worked up to its rated 
 maximum capacity. With magneto- machines the leading 
 wires, for distances up to 6lO feet, should be No. 16 Bir- 
 mingham gauge (0.065 inch), for distances of 800 feet, No. 
 14 (0.083 inch), and for distances of 1,000 feet, No. 13 
 (0.095 inch.) 
 
CHAPTER III. 
 
 THEORY OF EXPLOSIVES AND FUMES. 
 
 An explosion is a chemical reaction which is completed 
 in an exceedingly short period of time, with the evolution 
 of a large quantity of gas at a very high temperature. If 
 this reaction occurs in a body which is closely confined, the 
 expansive effort of the highly heated gases produces dis- 
 ruptive effects. If the suddenness of the reaction is very 
 great, disrupted action upon solid objects in contact with 
 the body may be obtained even when it is unconfmed, be- 
 cause the cohesion of these objects can be overcome more 
 readily in an instant of time than the inertia of the sur- 
 rounding air. This has given rise to the popular error 
 that nitroglycerine and other high explosives act down- 
 wards. Asa matter of fact they act with equal force in 
 all directions. It is evident, therefore, that the violence 
 of an explosion depends upon three things, viz. , the time 
 occupied in completing the reaction in the explosive body ; 
 the temperature produced by the reaction, upon which 
 directly depends the expansive force of the resultant gases; 
 and the quantity of gases evolved by the reaction. A 
 fourth consideration is whether the products of the re- 
 action are the result of one set of chemical changes occur- 
 ring simultaneously, or whether the set of new compounds 
 react upon each other, producing a second set of com 
 pounds. 
 
 [52] 
 
THEORY OF EXPLOSIVES AND FUMES. 53 
 
 EXPLOSION AND DETONATION. 
 
 It must be observed also that there are two general 
 classes of explosives : Those in which a process of oxida- 
 tion occurs, and those in which there is simple dissociation 
 of a compound without oxidation. Examples of the latter 
 are nitrogen chloride (trichloramide) whoss formula is 
 NCls. It explodes violently according to the reaction 
 
 2NC1 3 =N 2 +3C1 2 . 
 
 The explosion of basic tin nitrate, Sn 2 N 2 O 7 may be of this 
 character also, although it is possible that in its disso- 
 ciation the tin is set free in the nascent state and then 
 oxidized by the excess of oxygen present. Nitrogen 
 iodide and nitrogen bromide and similar compounds give 
 examples of simple dissociation without oxidation, 
 attended with powerful explosive effects. 
 
 In all the common explosives, on the other hand, there 
 is either simple oxidation or dissociation followed imme- 
 diately by oxidation of carbon, the carbon and oxygen being 
 contained in the explosive body. Hence such explosions 
 may be considered as analogous to ordinary combustion, 
 such as the burning of familiar combustible bodies, the 
 difference being only in the extreme rapidity of the re- 
 action. 
 
 Another distinction must now be noted between 
 different classes of explosives. We have observed that 
 explosives consist either of mechanical mixtures, such as 
 gunpowder, or chemical compounds, such as nitroglycerine 
 or guncotton. In the former class explosion occurs by 
 the reaction of the particles of the different substances in 
 
64 THEORY OF EXPLOSIVES AND FUMES. 
 
 the mixture upon each other, the explosion being propa- 
 gated from one group of such particles to the next, and 
 so on throughout the mass. An explosion so produced is 
 necessarily relatively slow. A shock, unless of extreme 
 violence so as to provoke sufficient friction, will not 
 cause it to explcde. The case is otherwise with explosive 
 compounds. Here the elements composing the substance 
 are combined into dennite molecules of uniform com- 
 position, held together by a relatively feeble chemical 
 attraction, i.e., they are unstable chemical compounds. 
 A shock will overcome the bonds which hold these ele- 
 ments together, upon which they are at once free to re- 
 acb upon each other, producing the gases at a high 
 temperature that give an explosive effect. An explosive 
 wave is thus generated, which is continued through the 
 entire mass. If the shock be sufficiently violent, the 
 energy of the initial wave will be reproduced uniformly 
 throughout the body, perfect combustion is accomplished 
 in an infinitely small space of time, and an effect of 
 peculiar violence is obtained, which has been called 
 "detonation." The same body may thus, according to 
 circumstances, be exploded or detonated. Some substances, 
 such as the fulminates and amides, always detonate, 
 while others, like guncotton, nitroglycerine and the 
 dynamite?, may yield either phenomenon. The differ- 
 ence is apparently only one degree, but it is of great 
 practical importance. Prof. Munroe, commenting on 
 Lambert's experiments remarks, 1 
 
 i Naval Institute, vol. x, p. 211. 
 
THEORY OF EXPLOSIVES AND FUMES. 55 
 
 "It is essential to observe that the explosive material 
 does not detonate because it transmits the movement, but 
 on the contrary because it arrests it, and because it 
 transforms on the spot the mechanical energy into 
 thermal energy, capable of suddenly raising the tempera- 
 ture of the substance up to the degree which will produce 
 its decomposition." 
 
 Again, reviewing the researches of Berthelot, he says : 2 
 " Although neither acetylene, cyanogen nor nitric 
 oxide can be detonated by simple heating, contact with 
 flame, or the electric spark, yet it was found that the 
 detonation of a small quantity of fulminate of mercury 
 would instantly detonate them. The study of explosive 
 matters presents analogous phenomena, for while with 
 dynamite, for instance, simple inflammation is insuffi- 
 cient to provoke detonation, this is effected under the 
 influence of special detonators, like fulminate of mercury, 
 which gives rise to a very violent blow. This is due, as 
 shown above, to the development of an explosive wave. 
 Berthelot holds that the superiority of fulminating 
 mercury as a detonator is not due solely to the rapidity 
 of its decomposition, but is due in a great measure to the 
 enormous pressure which it develops in detonating, a 
 pressure greater than that of any known body, and which 
 he estimates from his experiments to be equal to 40,000 
 kg. per sq. cm." (equivalent to 284.39 avoirdupois tons 
 per square inch.) "The rate of propagation of the ex- 
 plosive wave increases with the density of the loading." 3 
 
 2 Naval Institute, vol. viii., p. 304. 
 : Berthelot, Compt. Rend. 100, 314 : 1885, 
 
56 THEORY OF EXPLOSIVES AND FUMES. 
 
 The rate of propagation of the explosive wave in dynamite 
 upon detonation is from 7652 to 9030 feet per second. 
 Anything in a powder which interferes with the trans- 
 mission of the detonating impulse or wave will cause a 
 diminution in strength through imperfect detonation. 
 It requires 60 per cent, of nitroglycerine to make a 
 powder of kieselguhr which can be depended upon to ex- 
 plode at all. As the nitroglycerine is increased the 
 strength increases rapidly, through better transmission of 
 the impulse. Even taking 75 per cent, as ihe utmost 
 which the powder will safely hold, the detonation is not 
 perfect under ordinary conditions, though it approaches 
 it more nearly as the impulse is concentrated by stronger 
 confinement. 4 
 
 The effect of a rise of temp., rature is to bring all powders 
 nearer the point at which they will explode or detonate. 
 This heat effects a slight saving of work in explosion, so 
 th-it all explosives' are a little stronger in warm weather. 
 Deliquescent ingredients in dynamite tend to elevate its 
 temperature to a dangerous approximation to its ignition 
 point, as follows : The air confined in the cartridge con- 
 tains a slight quantity of moisture, which in uniting with 
 the deliquescent salt causes a depression in temperature, 
 which condenses fresh moisture from the surrounding 
 air. This being taken up reduces the temperature still 
 more, bringing a fresh supply, and so on. The process 
 continues until arrested by an outside elevation of tem- 
 perature, when the action is reversed. In losing moisture 
 
 * Lieut. W. R. Quinan, cited Naval Inst., vol. iv., p. 665. 
 
THEORY OF EXPLOSIVES AND FUMES. 57 
 
 the heat rendered latent is given out, which causes a 
 fresh loss of moisture and further elevation of tempera- 
 ture, and so on, till a change in atmospheric conditions 
 arrests the process. When absorbing moisture the dyna- 
 mite is comparatively weak and insensitive to blows and 
 compression ; when losing moisture it is comparatively 
 strong and very sensitive to both. The temperature being 
 already elevated, a slight blow will raise it to the explod- 
 ing point. The compression given by the tamping rod in 
 compacting it in the bore-hole may be sufficient to cause 
 a premature explosion. 
 
 While a nitrate mixture like gunpowder will not deton- 
 ate, it has been frequently claimed that if combined with 
 nitroglycerine a much greater power will be obtained. 
 This has been maintained by Quinan and by Drinker, 
 while others oppose it. The Judson R.R.P. powder is 
 designed to accomplish this. The ratio of efficiency 
 between gunpowder subjected to explosion and dynamite 
 detonated is approximately as 1: 2.26, and the ratio be- 
 tween dynamite and blasting gelatine, both detonated, is 
 asl :1.41. 
 
 An interesting practical illustration of the difference in 
 the effect of the same explosive compound when detonated 
 and when merely exploded is seen in the bursting of 
 cast-iron shells loaded with guncotton. Where no detona- 
 tion takes place the shell is broken into fragments of 
 various sizes and of irregular shapes, but whr n detonation 
 occurs the whole shell is reduced to very minute frag- 
 ments, and, what is more remarkable, two- thirds of the 
 
58 THEORY OF EXPLOSIVES AND FUMES. 
 
 total weight of the shell are found to be in approximately 
 rounded particles like peas, and in the form of fine 
 dust. 5 
 
 PRODUCTS OF COMBUSTION. 
 
 It has long been recognized that primary and secondary 
 reactions occur in the explosion of gunpowder. Various 
 theories, however, have been advanced to account for the 
 phenomena presented. Perhaps the best summary of the 
 results is that of Dr. Debus, who says : " The combustion 
 of gunpowder consists of two distinct stages : a process of 
 oxidation, occupying only a very small fraction of a 
 second, and causing the explosion, during which potassium 
 carbonate and sulphate, carbonic acid, some carbonic 
 oxide and nitrogen are produced, and a process of reduc- 
 tion succeeding the process of oxidation, and requiring a 
 comparatively long time for its completion. As the oxygen 
 of the saltpetre is not sufficient to oxidize all the carbon 
 to carbonic acid, and all the sulphur and sulphuric acid, 
 a portion of the carbon and a portion of the sulphur are 
 left free at the end of the process of oxidation. The car- 
 bon so left free reduces, during the second stage of the 
 combut tion, potassic sulphate, and the free sulphur de- 
 composes potassic carbonate. Hydrogen and marsh gas, 
 which are formed by the action of the heat upon the 
 charcoal, likewise reduce potassic sulphate, and some 
 hydrogen combines with sulphur forming sulphuretted 
 hydrogen." The principal reactions taking place he 
 represents by the following equations : 
 
 5 Prof, Munroe, Nav, Inst, vol. xxii., p. 628, 
 
THEORY OF EXPLOSIVES AND FUMES. 59 
 
 First stage 
 
 16KN0 3 + 13C + 5S=3K 2 C0 3 +5K 2 SO 4 +9CO 2 +CO+8N 2 
 
 Second stage 
 
 4K 2 C0 3 + 7S=K 2 SO 4 + 3K 2 S 2 +4CO 2 
 
 and 
 4K 2 SO 4 + 7C=2K 2 CO 3 +2K 2 S 2 +5CO 2 
 
 The possibility of dissociation is expressed by 
 
 K 2 CO 3 +K 2 S 2 +O 7 =2K 2 S0 4 +CO 2 
 
 The combustion of guncotton and of nitroglycerine pro- 
 ceeds along far simpler lines, from the nature of the sub- 
 stances involved. The reaction with guncotton is approxi- 
 mately : 
 
 2(C 6 H 7 O 2 )0 3 (N0 2 ) 3 =9CO+3C0 2 +7H 2 O+3N 2 
 
 That for nitroglycerine is written 
 
 2C 3 H 5 3 (NO 2 ) 3 =6CO 2 +5H 2 0+6N+0 
 
 The detonation of mercury fulminate gives 
 
 HgC 2 N 2 O 2 =Hg+2CO+N 2 
 
 The fumes resulting from the explosion or detonation 
 of ordinary blasting agents then contain as gaseous pro- 
 ducts carbonic acid, carbon monoxide, nitrogen and 
 vapor of water, with some free oxygen in the case of nitro- 
 glycerine. There is no doubt, however, that when nitro- 
 glycerine or dynamites are not properly detonated con- 
 siderable Quantities of carbon monoxide are evolved. 
 This goes far toward explaining its weaker explosive 
 energy under such circumstances, the heat of formation 
 being less, which proportionately reduces the expansive 
 effect of the gases. 
 
60 THEORY OF EXPLOSIVES AND FUMES. 
 
 PHYSIOLOGICAL EFFECT OK THE FUMES. 
 
 The deleterious gases resulting from the explosion of com- 
 mon powders are carbonic acid (CO 2 ), carbon monoxide 
 (CO) and nitrogen. The latter is evolved in compara- 
 tively small quantities, but its effect is the same as that of 
 carbonic acid, simple asphyxiation. A patient overcome 
 by carbonic acid and nitrogen, if rescued in time, will 
 speedily be resucitated by an ample supply of pure air. 
 The case is otherwise with carbon monoxide. This is a 
 poison. If carbon monoxide, or air containing it, be in- 
 spired, it gradually displaces the "oxygen, volume for 
 volume, out of the red corpuscles, and death soon occurs. 
 A very small quantity in the air (^ J^ t > YoVo) suffices in 
 a relatively short time to form a quantity of carbonic- 
 oxide-haemoglobin. In very partial poisoning with carbon 
 monoxide the blood gradually gets rid of it through the 
 respiratory organs. It does not appear that any part is 
 further oxidized into CO 2 in the organism. Carbonic- 
 oxide-haemoylobin, being a stable compound, circulates in 
 the blood vessels, but it neither gives up oxygen to the 
 tissues nor takes up oxygen in the lungs, hence its very 
 poisonous properties. The real cause of death in animals 
 poisoned with it is that the internal respiration is arrested. 
 Its effects are first stimulation, and afterwards paralysis 
 of the nervous system, as shown by the symptoms induced, 
 e.g., violent headache, great restlessness, excitement, in- 
 creased activity of the heart and respiration, salivation, 
 tremors and spasms ; later, unconsciousness, weakness 
 and paralysis occur, labored respiration, diminished heart- 
 
THEORY OF EXPLOSIVES AND FUMES. 61 
 
 beat, and, lastly, complete loss of sensibility, cessation of 
 respiration and heartbeat, and death. At first the tem- 
 perature rises several tenths of a degree, but it soon falls 
 one degree or more. The pulse is also increased at first, 
 but afterwards becomes very feeble and frequent. Where 
 the quantity of carbon monoxide is large (as is the case 
 after a blast in mines where the combustion of the explo- 
 sive has from any cause been imperfect), there is tempor- 
 ary, but pronounced, pa r alysis of the limbs, followed by 
 violent spasms. 6 
 
 Dr. Thomas Darlington, who treated 1,300 cises of 
 asphyxia, or partial asphyxia, and poisoning, from the 
 products of 'the explosion of dynamite during the construc- 
 tion of the new Croton Aqueduct, New York, contributed 
 an interesting paper on this subject to the Medical Record 
 (38, 661-662 ; 1890). He says : 
 
 41 Two classes of cases were observed : First, where a 
 considerable quantity of the products was inhaled at one 
 time acute cases; second, where the men constantly 
 breathed a small amount chronic cases. In some cases 
 where the amount of dynamite used was not large, or 
 where, after the explosion, a considerable quantity of fresh 
 air has been raised with the products of combustion, or 
 where the workman has after a few breaths become giddy 
 and is pulled away by others and sent to the surface, the 
 effects produced are a trembling sensation, flushing of the 
 face, succeeded sometimes by pallor, frequently nausea, 
 sometimes vomiting, with throb.bmg through the temples 
 
 Human Physiology. Dr. L. Landois, vol. i., p. 28, 1891. 
 
62 THEORY OF EXPLOSIVES AND FUMES. 
 
 and fulness in the head as if it would burst, followed by 
 an intense headache characteristic of poisoning by nitrites, 
 frequently lasting 48 hours. The heart's action is increased 
 and the pulse full and round, though somewhat compres- 
 sible. Where, however, a man goes into the tunnel im- 
 mediately after the explosion, and is brought in contact 
 with a large percentage of the poisonous materials, the 
 effects are giddiness immediately followed by unconscious- 
 ness, and the patient presents the usual appearance of 
 asphyxia. Sometimes in these cases the pulse is full and 
 bounding, though very compressible ; but in most cases it 
 is alarmingly weak. Generally there is great pallor. The 
 comatose condition soon passes away, and is succeeded by 
 drowsiness, languor, cold perspiration, intermittent pulse, 
 and generally nausea and vomiting. Sometimes the 
 breathing is spasmodic, and frequently there is hiccough, 
 and after a time a severe headache. Nearly all of these 
 cases no matter how serious they seem at the time, 
 recover, though a substitute during my absence was on 
 one occasion so unfortunate as to lose two cases. Death 
 in these cases occurred several hours after the patients 
 were removed from the tunnel, and was due to paralysis 
 of respiration 
 
 " In the chronic cases there are four prominent symp 
 toms, headache, cough, indigestion and disturbances of 
 the nervous system. The cough is similar in character to 
 the cough of pertussis, or of malaria. In nearly all of the 
 cases there was a continuing headache. Next in prominence 
 come disturbances of the nervous system, such as tremb- 
 
THEORY OF EXPLOSIVES AND FUMES. 63 
 
 ling, irritability, neuralgia, etc. Nearly if not all the 
 symptoms were attributable to this cause. Even the 
 cough, in all probability, was due to the effect produced 
 on the pneumogastric nerve. As soon as a man with these 
 chronic symptoms was taken from the tunnel and placed 
 at work on top, he steadily improved, and would finally 
 recover entirely. Those who had previously suffered from 
 dyspepsia or neuralgia were made much worse by the 
 dynamite smoke." 
 
 Dr. Darlington attributes much of the trouble experi- 
 enced to the volatilization of nitroglycerine, which failed 
 to explode. c ' The similarity of symptoms from inhalation 
 of the products of the explosion of dynamite, and of those 
 produced by the nitroglycerine itself, is so well marked 
 that even miners themselves have noticed it. Frequently, 
 when dynamite is frozen, a miner will place a cartridge in 
 his boot to thaw it out, and the absorption of nitroglycer- 
 ine through the skin will produce precisely the same 
 symptoms as in the mild acute cases of the inhalation of 
 the products before described. Again, I know an instance 
 where a miner used his knife to cut a cartridge, and after- 
 ward cut and ate an apple with the same knife. In this 
 case the symptoms were the same as those produced by 
 powder smoke, only more severe. The headache persisted 
 3 weeks." He states that he proved the existence of free 
 nitroglycerine in the air after explosions of dynamite by 
 waving a glass plate in the fumes and condensing it there- 
 on, subsequent tests proving it to be this substance. He 
 remarks rather pertinently, 4< The use of a large cap will 
 
64 THEORY OF EXPLOSIVES AND FUMES. 
 
 explode a greater percentage of the glorioine 7 than a small 
 one, and this, to a certain extent, obviates the trouble. 
 In certain cases, however, a cartridge does not explode, 
 but burns like a candle, with considerable sputtering. ]n 
 such an instance the amount of nitroglycerine volatilized 
 is much greater than if exploded, and consequently the 
 effects far more deleterious. I have witnessed a whole 
 shift 'knocked out' from this cause," 
 
 Concerning the effects of nitroglycerine Dr. T. Lauder 
 Brunton says, 8 " Its action is much like that of nitrite of 
 amyl and other nitrites. It causes depression, with very 
 rapid pulse and respiration, paralysis of reflex action and 
 voluntary motion, loss of sensation and death by stoppage 
 of the respiration. It agrees with nitrites in acting as a 
 poison to muscle. The spinal cord appears to be para- 
 lyzed before the cerebral ganglia. It diminishes the 
 oxidizing power of the blood and communicates to it a 
 chocol-ite color like nitrites, and like them it also lessens 
 the blood pressure. In some persons it produces head- 
 ache, even in exceedingly minute doses. The reasons 
 why nitroglycerine acts more powerfully than nitrites 
 probably are that the whole of it is absorbed without 
 decomposition, and the nitrous acid, being set free in the 
 blood in a nascent condition, is more active than it would 
 otherwise be." 
 
 It is evident that a mistake might easily be made in 
 diagnosis between a case of poisoning by carbon monoxide 
 
 7 Glonoine is the medical term for nitroglycerine. 
 
 s " Pharmacology, Therapeutics and Materia Medica," 1885, p. 712. 
 
THEORY OF EXPLOSIVES AND FUMES. 65 
 
 (CO) and nitroglycerine, by depending upon superficial 
 symptoms only, and Dr. Darlington has probably ascribed 
 undue importance to the possibility of inhalation of free 
 nitroglycerine in the fumes. Many of his acute cases 
 were doubtless the results of carbonic oxide poisoning, 
 the existence of which in the products of combustion of 
 dynamite, especially when imperfect, he seems to have 
 overlooked. 
 
 The line of treatment pursued by Dr. Darlington, the 
 value of which is proven by his eminently successful 
 results, is as follows : The usual procedure in cases of 
 asphyxia. In addition to this, the uss of cold applications 
 to the head, and of atropine, ergotine or other vaso-motor 
 stimulants, administered sub-cutaneously. Acting on the 
 assumption that a nitrite is formed in the blood from the 
 decomposition of nitroglycerine, he also treats his cases 
 with inhalation of ammonia, and also gives the carbonate 
 and aromatic spirits of ammonia internally. He recom- 
 mends that workmen carry with them small vials of aro- 
 matic spirits of ammonia for immediate use in cases of 
 necessity. 
 
CHAPTER IV, 
 
 TRANSPORTATION, STORAGE AND HANDLING. 
 
 TRANSPORTATION . 
 
 In the transportation of explosives by ordinary road 
 vehicles the points to observe are : First, the vehicle 
 should be inspected to make sure that it is in good condi- 
 tion, and not liable to breakage, and that it contains no 
 projecting metal parts inside the bed. Second, that the 
 cases containing the explosive are securely packed to pre- 
 vent movement against or upon each other, or upon the 
 sides and bottom of the bed. A small quantity of clean 
 straw on the bottom of the bed and -between the cases is 
 a valuable precaution, especially when the explosives are 
 to be hauled over rough roads. After unloading, the 
 straw must be gathered together and burned at a safe 
 distance from the explosives. Third, the cases must be 
 covered in damp weather with a waterproof canvas or 
 tarpaulin. In warm weather a white canvas cover over 
 the vehicle is important to prevent undue heating from 
 the sun. Fourth, the vehicle should always carry con- 
 spicuously displayed a signal flag to give warning of 
 danger. Fifth, where possible, always avoid passing 
 through a town, or the more densely populated portions 
 of a town or settlement. Sixth, where necessary to pass 
 through a town, do so quickly, without making any stop- 
 [66] 
 
TRANSPORTATION, STORAGE AND HANDLING. 67 
 
 pages for any purpose. These or similar precautions 
 are made obligatory by law in most counties. 
 
 For transportation of small lots of explosives around 
 mines and quarries, they may be sent in tramcars, or 
 lowered in skips, buckets or cages. Warning should 
 always be given of the approach of such a cargo, and 
 when feasible this work should be done between " shifts" 
 so as to expose as few men as possible to danger. Only 
 experienced and trusty men should be detailed for service 
 of this kind. The carrying of a case on the shoulder is 
 often the safest mode of conveyance of a small quantity. 
 Under no circumstances should explosives be carried up 
 or down ladders in a mine, except in very small quanti- 
 ties to working places for immediate use in the charging 
 of bore-holes. 
 
 The regulations governing transportation by railroads 
 vary with the roads themselves, more or less limited by 
 legislation. The Ontario regulation contained in R.S.O. 
 c. 207, s. 41, ss. 12 and 13, is as follows : 
 
 (12) No person shall be entitled to carry, or to require 
 the company to carry upon their railway, aqua fortis, oil of 
 vitriol, gunpowder lucifer matches, or any other goods 
 which in the judgment of the company are of a danger- 
 ous nature ; and if any person sends by the railway such 
 goods without, at the time of so sending the said goods, 
 distinctly marking their natuie on the outside of the 
 package containing the same, and otherwise giving notice 
 in writing to the bookkeeper or other servant of the 
 company with whom the same are left, he shall forfeit to 
 the company the sum of $20 for every offence. 
 
68 TRANSPORTATION, STORAGE AND HANDLING. 
 
 (13) The company may refuse to take any package or 
 parcel which they suspect to contain goods of a dangerous 
 nature, or may require the same to be opened to ascertain 
 the fact. 
 
 The Dominion Regulation, 51 V. c. 29, ss. 253 and 254, 
 is as follows : 
 
 (253) No passenger shall carry, or require the company 
 to carry upon its railway, aqua f ortis, or oil of vitriol, gun- 
 powder, nitroglycerine, or any other goods which, in the 
 judgment of the company, are of a dangerous nature; and 
 every person who sends by the railway any such goods 
 without at the time of so sending the same, distinctly 
 marking their nature on the outside of the package con- 
 taining the same, and otherwise giving notice in writing 
 to the station master or other servant of the company 
 with whom the same are left, or who carries or takes upon 
 any railway train such material as is mentioned above, 
 for the purpose of having the same carried by the said 
 railway train, shall forfeit to the company the sum of five 
 hundred dollars for every such offence. 
 
 (254) The company may refuse to take any package or 
 parcel which it suspects to contain goods of a dangerous 
 nature, or may require the same to be opened to ascertain 
 the fact ; and the company shall not carry any such goods 
 of a dangerous nature, except in cars specially designated 
 for that purpose, on each side of each of which shall 
 plainly appear in large letters the words, " dangerous 
 explosives," and for each neglect to comply with the provi- 
 sions of this section the company shall incur a penalty 
 of five hundred dollars. 
 
 The British law on this subject is very elaborate and 
 explicit, as it is concerning the whole matter of explo- 
 sives. The Secretary of State is given the widest author- 
 ity in the making of regulations governing the transporta- 
 
TRANSPORTATION, STORAGE AND HANDLING. 69 
 
 tion of explosives, and every harbor authority is empow- 
 ered to make by-laws, with the sanction of the Board of 
 Trade, regulating the conveyance, loading and unloading 
 of gunpowder and other explosive substances. The orders 
 of the Secretary of State prohibit the carriage of more 
 than 5 Ib. of any explosive in conveyances also used for 
 passengers, and the carriage of fulminates, ammunition 
 and fireworks in such conveyances is forbidden. Fulmin- 
 ates, ammunition and fireworks may not be carried in the 
 same conveyance with other explosives unless a suitable 
 distance for safety is maintained between them. Minute 
 directions are given as to the packing of the cases in con- 
 veyances ; separation from dangerous substances and 
 sources of fire and heat ; avoidance of centers of con- 
 gested population ; reliability and behavior of men in 
 charge of the explosives ; unloading, etc. x 
 
 44 The quantity of explosive to be conveyed in any one 
 carriage or boat shall not exceed 2,000 Ib., unless the 
 carriage be so enclosed on all sides with wood and metal, 
 or the boat have a close deck so closed as to effectually 
 protect the explosive against accident by fire from with- 
 out, in which case the amount of explosive conveyed shall 
 not exceed the following : 
 
 In any one carriage on a private railway, whether 
 
 worked by steam or otherwise 10,000 Ib. 
 
 In any other carriage 4,000 Ib. 
 
 In any one boat 50,000 Ib. 
 
 44 When two or more carriages or boats conveying explos- 
 ive exceeding in the aggregate the amount allowed by the 
 preceding regulation to be conveyed in one such carriage 
 
 i Guide Book to the Explosives Act, 1875, 10th ed., pp. 172-180, and 
 325-330. 
 
70 TRANSPORTATION, STORAGE AND HANDLING. 
 
 or boat are traveling together, a space of at least 50 
 yards shall be kept between each such carriage or 
 boat, and every other such carriage or boat, unless 
 circumstances render it impracticable, or unless, in the 
 case of a train on a private railway, three or more vans 
 not containing inflammable or explosive goods intervene 
 between such carriage and every other such carriage." 2 
 
 It will be found that governmental regulations touch- 
 ing such matters are usually more elastic than the self- 
 imposed safeguards of the common carriers of widest ex- 
 perience. As an example of such voluntary regulations 
 by a railroad, company may be cited those which went into 
 force on September 25, 1899, on the Pennsylvania rail- 
 road, a line which handles perhaps a larger quantity of 
 explosive materials than any other in the world, and which 
 has consequently had the most extensive experience. In 
 order to show the degree of care which this corporation 
 finds it advisable to take as part of its business policy, the 
 order is quoted nearly in full. 
 
 1. Explosives will be received for transportation over 
 the above lines (P.R.R., r>.W. & B. R.R., N.C.S. Ry., 
 and W. J.& S R.R.) branches, and immediate connections 
 under their control, only under the following regulations. 
 
 2. The safe transportation of explosives is believed to 
 be largely influenced by the manner in which the explo- 
 sives are packed for shipment. Furthermore, informa- 
 tion in regard to the kind of explosive that is being trans- 
 ported is essential, in order that the railroad employes 
 may not ignorantly do anything to incur danger. 
 
 2 Guide Book to the Explosives Act, 10th ed., p. 329. 
 
TRANSPORTATION, STORAGE ASTD HANDLING. 71 
 
 3. Classification. For transportation purposes all ex- 
 plosives will be divided into the following groups : Com- 
 mon Black Powder, High Explosives, Smokeless Powders, 
 Fulminates, Ammunition and Fireworks. 
 
 4. Common Black Powder. When these exp'osives are 
 packed in packages containing less than 20 Ib. each, these 
 packages must be enclosed in a wooden box in such a way 
 that the filling hole is up, and the boxes when filled must 
 not weigh over 100 pounds. Each box must have sten- 
 ciled on top: "Common Black Powder." The prismatic 
 powders must be packed in tight tin boxes, which must 
 be enclosed in a wooden box. The whole package must 
 not weigh over one hundred pounds, and must be sten- 
 ciled as above. When twenty pounds or over of sporting, 
 rifle or blasting powder are contained in one package, this 
 package is preferably a wooden keg or cask. If iron kegs 
 or casks are used, it is desired that they be enclosed in a 
 wooden jacket, but naked iron or steel kegs or casks will 
 be received. These naked kegs or casks must be so well 
 made, and the filling hole so well secured, that when filled 
 with the same weight of sand as they are designed to 
 carry of powder, and dropped in any manner a distance of 
 four feet on a rail, they will not be ruptured and none of 
 the sand will escape. These explosives will not be received 
 in packages containing over one hundred pounds each, 
 except for export, when larger packages will be received. 
 Each package must be stenciled as above. 
 
 High Explosives. 5. Under high explosives are em- 
 braced all explosives more powerful than ordinary black 
 powder r excepting smokeless powders and fulminates. 
 These include those known under the various trade 
 names of Acme, JEtna, Atlas, Climax, Commercial, Pitt- 
 mar, Dynamite, Forcite, Fumeless, Giant, Hecla, Her- 
 cules, Joveite, Big Chief, Judson, Samson, Rend-Rock, 
 Rack-a-Rock. etc., etc. The following regulations will 
 apply to explosives of this group : 
 
72 TRANSPORTATION, STORAGE AND HANDLING. 
 
 6. No explosive of this group will be received for ship- 
 ment in the liquid or bulk form. Explosives like Rack-a- 
 Rock, one constituent of which is liquid, will be received 
 provided the liquid is not itself explosive, and provided 
 the liquid is not packed in the same boxes with the other 
 constituent. High explosives must be made up into 
 cartridges, and the cartridges must be so arranged in the 
 boxes that when the boxes are leaded top-side up all 
 cartridges will lie on their sides, and never on their ends. 
 Each package must be plainly stenciled, "High Explosive 
 Dangerous," on top and one side or ends. Explosives 
 which consist of a liquid combined or mixed with an 
 absorbent material must have the ingredients uniformly 
 mixed and the liquid constituent thoroughly absorbed. 
 The amount of the liquid constituent must be such that 
 the temperature of the hottest summer day will not occa- 
 sion leakage. The shells or cases consisting of paper or 
 other material used in making the cartridges must be of 
 such material, or be so treated, that the liquid constituent 
 of the explosive will under no circumstances be absorbed 
 by th encase or shell. 
 
 Sections 7 to 10 refer to smokeless powders, which, be- 
 ing employed solely for military and sporting purposes, 
 are not discussed in this Hand-book. 
 
 Fulminates. 11. Under fulminates for the present is 
 included only fulminate of mercury in bulk form that is, 
 not made up into percussion caps, detonators, blasting 
 caps or exploders. Fulminate of mercury in bulk must 
 contain when packed not less than 25% of water, and must 
 in this wet condition be placed in a twelve-ounce duck 
 bag and securely tied. This duck bag must then be 
 placed in a rubber bag, which rubber bag must then be 
 filled with water and securely tied. The rubber bag and 
 contents must then be placed in a tight cask, the empty 
 spaces around the bag filled with sawdust, the cask closed 
 
TRANSPORTATION, STORAGE AND HANDLING. 73 
 
 and filled with water, then bunged and sealed. Each 
 cask must be stenciled, 4 Fulminate.' " 
 
 12. Under ammunition are embraced cartridges to be 
 used in sporting or fowling pieces, etc. , etc. . . . Also 
 under ammunition are embraced detonators, blasting caps, 
 percussion caps, fulminators, exploders, track caps, fog sig- 
 nals, and other articles of like nature. The following 
 regulations apply to ammunition : 
 
 13. Cartridges c-r ammunition must be packed in 
 pasteboard or other boxes, and these pasteboard or other 
 boxes must be again packed in strong wooden boxes, not 
 too large or heavy to be readily handled by one person. 
 Each package or case of ammunition must be plainly 
 stenciled " Ammunition Handle Carefully." . . . 
 
 Sections 14 and 15 apply to fireworks. 
 
 Loading Explosives Together. 16. Black powder, high 
 explosives and smokeless powder of all kinds may be 
 loaded together in the same car. Fulminate, ammuni- 
 tion and fireworks must never be loaded with each other, 
 nor in the same car with common black powder, high 
 explosives or smokeless powder. . . . 
 
 Shipping Days. 17. Common black powder, high ex- 
 plosives, smokeless powders and fulminates, in car-load 
 lots, will be received (when laws or ordinances permit) on 
 any day except Saturday, and in less than car loads on 
 Mondays and Thursdays of each week. Ammunition and 
 fireworks will be received at any time, and may be loaded 
 with other freight, except as provided in section 16, 
 but should if possible be loaded so as to avoid transfer 
 stations. 
 
 ^Then follow regulations as to shippers' certificates, and 
 certificates of inspection of the car containing explosives, 
 etc. 
 
74 TRANSPORTATION, STORAGE AND HANDLING. 
 
 Selection and Preparation of Gars. 23. Only box 
 cars which have been specially selected and specially 
 inspected will be used in the transportation of the first 
 four groups of explosives, and they must be in first-class 
 condition in every respect, both inside and outside. The 
 following points must be carefully looked after : The car 
 must in no case have loose boards or cracks in the roof or 
 sides, and the doors must shut so closely that no sparks 
 can get in at the joints. When these explosives are 
 loaded in car loads the doors must be stripped, except 
 when the cars are equipped with Wagner doors, which 
 must not be stripped. The journal boxes and trucks 
 must be examined, and so cared for as to reduce to a 
 minimum the probability of hot-boxes or other failure, 
 requiring the car to be set off before reaching its destina- 
 tion. The car must be carefully swept before it is loaded, 
 and a careful inspection made of the inside. Hides in the 
 floor or lining must be repaired, and special care taken to 
 see that there are no projecting nails or bolts, or pieces of 
 metal which may work loose and produce holes in pack- 
 ages of explosives during transit. Short pieces of hard 
 wood, two-inch plank, must be spiked to the floor over 
 the king bolts to prevent the possibility of their wearing 
 through the floor and into the packages of explosives. 
 
 24. Agents and car inspectors at junction points must 
 refuse to receive from connecting lines cars loaded with 
 these explosives unless the requirements of Section 23 
 have been complied with. 
 
 Handl'ng of Explosives. 25. In handling packages of 
 explosives at stations and in cars the greatest care must 
 be taken to prevent their falling or getting shocks in 
 any way, and they must not be thrown or dropped, but 
 must as far as practicable be passed from hand to hand,*or 
 carried by one or more persons, and must not be rolled 
 on the platform or car floor, unless they are so heavy that 
 this cannot be avoided. The agent must choose careful 
 
TRANSPORTATION, STORAGE AND HANDLING. 75 
 
 men to handle explosives, must see that the platform and 
 feet of the men are as free as possible from grit, and must 
 take all possible precautions against fire. No unauthor- 
 ized person must have access to the explosives at any time 
 while they are on the property of the Company. Should 
 any packages of high explosives when offered for ship- 
 ment show outward signs of any oily stain or other indi- 
 cation that absorption of the liquid part of the explosive 
 in the absorbent material is not perfect, or that the 
 amount of the liquid part is greater than the absorbent 
 can carry, THE PACKAGES MUST BE REFUSED IN 
 EVERY INSTANCE AND MUST NOT BE ALLOWED 
 TO REMAIN ON THE PROPERTY OF THE COM- 
 PANY. 
 
 26. A1J the articles enumerated in Section 12, under 
 the heading Ammunition, also fireworks and friction 
 matches, or other articles of like nature, must under no 
 circumstances be loaded in the same car with the other 
 kinds of explosives provided for in this circular ; nor 
 when unloaded be put near those explosives in the freight 
 station. 
 
 Loading in Car. When explosives are packed in boxes, 
 the boxes must be so loaded in the cars that they will lie 
 flat, top-side uppermost. They must never be loaded on 
 their sides or ends. When explosives are packed in 
 round kegs containing from 20 to 100 lb., they must be 
 loaded on their sides in rows across the car. Larger 
 casks, barrels or drums may be loaded on their sides or 
 ends as will best suit the conditions. Whatever the kind 
 or form of packages, it is essential that after they are 
 loaded THEY SHALL BE SO STAYED THAT THEY 
 CANNOT CHANGE POSITION UNDER THE OR- 
 DINARY SHOCKS OF TRANSPORTATION. Especi- 
 ally must care be taken that they cannot fall to the floor 
 or have anything fall 011 them during transit. 
 
76 TRANSPORTATION, STORAGE AND HANDLING. 
 
 Section 28 gives instructions as to the marking of cars 
 to indicate their dangerous contents, and Section 29 allows 
 safety fuse, if properly boxed, to be loaded with other 
 explosives. 
 
 Handling Car Containing Explosives. 30. Every person 
 handling explosives in car-load lots or less must exercise 
 the greatest c.ire to prevent accidents. A car containing 
 explosives must be hauled as near the middle of a train as 
 possible, and must not be placed next to a car loaded with 
 oil or other inflammable material. The locomotive must 
 remain attached to the car or to the draft containing a 
 car of explosives in handling it to or from a siding, if pos- 
 sible. When this can not be done, a rope or pole must 
 be used, but a flying switch must not be made with a car 
 containing explosives. Other cars must not be allowed to 
 strike a car loaded with explosives, and such a car must 
 be so placed in a yard or at a station that it will be sub- 
 ject to as little handling as possible, and that it wiil be 
 exposed to as little danger from fire as possible. At every 
 point at which a train stops the trainmen in charge must 
 make a special examination of a car containing explosives, 
 or other dangerous or inflammable articles, and must 
 carefully examine the journal boxes with a view to locat- 
 ing or preventing hot boxes on these or adjacent cars. If 
 it should be necessary to cut off, short of its destination, 
 any car containing explosives, the conductor must advise 
 the agent at the station where the car is cut off, and must 
 also advise his superintendent from the first telegraph 
 office. The agent at the point at which the car is cut off 
 must use every possible precaution to prevent accident 
 while the car is under his control. 
 
 In Case of a Wreck. 81 . In case of a wreck involving 
 a car containing explosives, the first and most important 
 precaution is to prevent fire. Although most of the group 
 4 'high explosives" will burn in small amounts quietly, 
 
TRANSPORTATION, STORAGE AND HANDLING. 77 
 
 and without causing a disastrous explosion, yet it must be 
 remembered that it is the characteristic of most explo- 
 sives to burn, and consequently everything possible must 
 be done to keep fire away. 3 Before beginning to clear a 
 wreck in which a car containing explosives is involved, all 
 unbroken packages should if possible be removed to a 
 place of safety, and as much of the broken packages as 
 possible gathered up and likewise removed. Further- 
 more it should be borne in mind that " high explosives" 
 are readily fired by a blow, and all explosives, except 
 when they are wet, by the spark produced when two 
 pieces of metal, or a piece of metal and a stone, come 
 violently together. In clearing a wreck, therefore, care 
 must be taken not to strike fire with the tools, and in 
 using the crane or locomotive to tear the wreckage in 
 pieces t>he possibility of .producing sparks must be con- 
 sidered. With such explosives as "common black pow- 
 der," "smokeless powders," and ' fulminates," thorough 
 wetting with water practically remove* all danger of ex- 
 plosion by fire, spark, or blow; 4 but with the "high 
 explosives " wetting does not make them safe from blows. 
 With all explosives, mixing with damp earth renders them 
 safer either from fire, spark or blow. In case " fulmin- 
 ate " has been scattered by a wreck, the ground involved 
 must, after the wreck has been cleared, be saturated with 
 oil. If this is not done, when the ground and fulminate 
 get dry small explosions will constantly occur whenever 
 the mixed material is trodden on or struck with any blow. 
 
 STORAGE. 
 
 Local conditions have much to do with the type of 
 structure to be built for an explosives magazine. In 
 
 The regulations should have called attention to the fact that most 
 explosives in bulk, after burning a short time, become heated thereby to 
 their exploding temperature, and then explode with violence. 
 
 * Fulminates are not insensible to friction when wet. 
 
78 TRANSPORTATION, STORAGE AND HANDLING. 
 
 general, it may be said, the lighter the construction the 
 better. By the law of Austria all magazines must be 
 built of such materials, and in such a manner, that in the 
 event of an explosion the building will be completely dis- 
 integrated, and no pieces will be thrown to a distance. 
 Thus the radius of danger is reduced to a minimum. 
 The only points in favor of more solid construction are 
 safety from fire and from burglars. The latter danger 
 has been considered important in Great Britain, so that 
 very substantial structures are there required. In Am- 
 erica this precaution is of little moment, so that, in open 
 country, where a sufficient zone can be obtained free from 
 inflammable materials, the light construction is preferable. 
 
 Storage in caves, tunnels, earth- or stone-covered vaults 
 and in log structures should under no circumstances be 
 tolerated. The chief objection in all these cases is that 
 the structure will hold dampness, and any dampness in a 
 magazine containing any explosive into which nitrates 
 enter as an essential or accessory ingredient is certain to 
 affect its quality and render it more or less dangerous in 
 subsequent use. This applies to gun-powder (common 
 black powder) and to practically all dynamites, especially 
 those made in America. It does not apply to kieselguhr 
 dynamite of foreign manufacture. 
 
 A suitable building is one made of common weather- 
 boarding on a framework of 2 by 4 inch stuff, with a 
 tight flooring of tongued and grooved boards, blind 
 nailed, and with walls and ceiling sealed with the same 
 material. The roof should be of tarred paper. Where 
 
TRANSPORTATION, STORAGE AND HANDLING. 79 
 
 danger of fire is apprehended the lightest steel shingles 
 may be used on the roof and outer walls. The door should 
 be heavy, and should in all cases open outwards. Open- 
 ings for ventilation should be provided around the 
 bottom, protected by wire screens or otherwise against 
 the entrance of vermin, and so constructed that water 
 cannot enter. A hooded ventilating pipe should extend 
 from the ceiling through the roof. In regions where dan- 
 ger of explosion from rifle balls is to be apprehended, 
 safety may be insured by constructing inside the maga- 
 zine a wainscoting^ with a space of 6 inches between it 
 and the wall, made sufficiently tight to hold fine dry 
 sand, with which the interspace should be closely filled. 
 If this is made as high as the top of the pile of cases 
 holding the explosives, and the sand is well compacted 
 and confined by boards covering the sand-space, no rifle 
 now manufactured will be able to send a ball through this 
 sand, even if fired as close as 25 feet from the magazine. 
 This has been carefully tested by the author, using all 
 grades of sporting rifles, and finally the Lee-Metford with 
 its nickel-steel shell. In the latter case the maximum 
 penetration, out of a large number of shots fired into 
 sand confined in wooden receptacles, ac a range of 
 24 feet 7| inches measured from the muzzle of the rifle to 
 the outside of the box, was 5 inches. In all cases the rear of 
 the nickel-steel shell was found to be intact, but the point 
 had been completely demolished, and the lead filling of 
 the shell, on account of its greater momentum, had 
 '* spilled forward," and had been turned back by the 
 
80 TRANSPORTATION, STORAGE AND HANDLING. 
 
 resistance of the sand like the head of a mushroom, with 
 the empty shell constituting the stem. The average pene- 
 tration of lead bullets from ordinary sporting rifles was a 
 little over 3^ inches at a range of 25 feet. 
 
 As a type of a suitable brick or stone structure the fol- 
 lowing specifications furnished by the Acadia Powder Co., 
 of Halifax, N.S., are submitted : 
 
 General specifications. Brick magazine, (1,000 to 1,600 
 kegs of black powder or 15 to 20 tons of dynamite.) 
 
 Foundations of good ru ble masonry, 24" wide ; 
 outside measurement, 16' 2" x 20' 2" ; height, 6" above 
 natural surface of ground ; depth according to location, 
 average 4'. 
 
 Brickwork, 16' x 20' outside. Side walls, 16" (2 bricks) 
 wide up to string course for joists to rest on. Said course 
 to be a plank 2J" x 8", flush with inside brick work, at such 
 height above foundations that bottom of joists may come 
 6" above highest average snowfall. Where there is no 
 snowfall nor danger of inundation, joists may rest directly 
 on foundations. End walls, 1| bricks wide. Above string 
 course, building to be 14' x 18' inside ; 1st course, 12" 
 (1 bricks wide) ; 2nd course, 10" (1J bricks) all around 
 building except buttresses, 12" wide and 16" (2 bricks) 
 face, carried up at each corner and in centre of rear and 
 end walls ; 3rd and following course, 8" (1 brick) wide, 
 headers in every sixth course. Side walls to be 8' high 
 from bottom of joists to top of plate, the two upper 
 courses being brought out, half each, to the line of but- 
 tresses, so as to form a brick cornice. End walls to be for 
 double pitch roof, 1 to 3, ridge 10' 8" above string course: 
 
 Door frame set in centre of one side so that top of sill 
 may be 9" above string course and J" below floor when laid. 
 
 Two blind ventilators, 2^" x 3" section, in each end wall 
 in first course above the floor ; outer opening 4' from cor- 
 
TRANSPORTATION, STORAGE AND HANDLING. 81 
 
 iier of building : inner opening 6" nearer end walls, with 
 right-angled turns connecting them to prevent possibility 
 of thrusting anything through. 
 
 Wall strips, 2%" x 4J", projecting from wall J" to J" 
 for attaching upright furring, built in around inside of 
 building, one about 12" from the floor, another same dis- 
 tance below plate. 
 
 Blind ventilator in each gable, same section as those 
 above floor, but having outside opening 6" above the 
 inner one, instead of at one side. 
 
 Rafters, 3" y 4", built into each gable, flush with inside 
 of wall. 
 
 After other rafters are in position, side walls carried up 
 on inside above plate until they reach the sheathing. 
 
 All bricks to be well burnt, well laid and well pointed. 
 The brick work as far up as the string course may be 
 grouted. 
 
 Joists, 15 pieces, 3" x8". 
 
 Flooring of good second quality, 1J" stuff, thoroughly 
 dry, planed one side, tongued and grooved, and blind 
 nailed so that no nails may be exposed. 
 
 Plate, 2J" x 4", flush with inside of wall. 
 
 Intermediate rafters, 8 pieces 3" x 6", notched over plate 
 so that upper side may be flush with edge of brick cornice ; 
 halved and well nailed at ridge. 
 
 Ties, V x 8", strongly nailed to each rafter and resting 
 on plate. 
 
 Roof sheathing of good common V boards, projecting 2" 
 on all sides of building. 
 
 Roofing of good tin plate, well laid either with diagonal 
 turned or upright soldered seams, brought down around 
 and under the projected sheathing so as to cover all wood- 
 work of roof. Where obtainable, one layer of tarred 
 roofing paper placed under the tin. 
 
 Furring of cheap culls 4" x V or 4" x {", about 6' long 
 and 4" apart, to be nailed on each side of the wall strips. 
 
82 TRANSPORTATION, STORAGE AND HANDLING. 
 
 not coming nearer than 6" bo floor, object being only to 
 secure ventilation and prevent powder touching the brick 
 walls. 
 
 Door frame, 3' x 6' 6" clear. Sill of oak, maple or birch, 
 3" x 9" x 4' ; planed on top and front, and top bevelled for 
 3". Jambs of clear dry stuff, 1%' x 6", planed and rabitted 
 and well mortised into sill and cap flush with inside of 
 building. False cap, f " x 4 |" gained or mortised into 
 jambs. Cap of hard wood or good spruce, 3"x9"x5', 
 pinned to jambs and built into brickwork after wall has 
 reached height of latter, planed where surface is exposed. 
 
 Door opening outward, in two leaves, either double 
 diagonal or strong battened. May be advantageously 
 covered with sheet iron 1-16" to J" thick. Good strong 
 hinges. When shut, one leaf fastened to both cap and sill 
 by strong bolts, the other by strong and well fastened 
 rim lock, having two keys of unusual pattern. Brass 
 trimmings are desirable but not essential. 
 
 Outside of metal roof painted with one coat best white 
 lead and one of mineral paint ; sill, cap and door with 
 two coats of white lead, the second being tinted. 
 
 Considerable difference of opinion has existed regard- 
 ing the danger from lightning. The Swiss Committee on 
 the physical properties of dynamite (1870) reported that 
 "thunderstorms and lightning involve no special danger 
 to dynamite. . . . But if well confined, and if the 
 temperature produced by the lightning be high enough, 
 an explosion may possibly take place." Prof. Munroe 
 severely criticises neglect of lightning protection, and sug- 
 gests that "a network of metal rods carried over the tops of 
 those magazines whose roofs are slated, and given a suf- 
 ficient ground connection, would be a complete protec- 
 tion." Guttmann also insists on protection, and advocates 
 
TRANSPORTATION, STORAGE AND HANDLING. 
 
 83 
 
 an idea of Melsens. " It consists in surrounding the 
 building either completely with a network of wires or in 
 conducting along the roof-edges and corners of the build- 
 ing barbed wires which are earthed (grounded) at several 
 places. 5 "In general it is agreed that the earth plate 
 should be as large as possible and that it should be put 
 either into water or into permanently moist soil, or, if 
 neither of these be available, into a pit filled with coke." 6 
 The distances allowed by the British law between 
 magazines and other buildings, highways, etc.. is given 
 somewhat abbreviated below. 
 
 
 Distances to be kept clear from 
 
 
 >^o & 
 
 g i > 
 
 
 ^ 
 
 
 4*s 
 
 e -^ 
 
 
 "C 
 
 
 610 c ^ 
 
 |Sfi 
 
 
 4; tl 
 
 Amt. of explosive to 
 be allowed in 
 magazine. 
 
 rf^ 
 
 III 
 
 Public 
 Railwajr 
 
 r c 
 p 
 
 
 l-i-g-o 
 
 &fj 
 
 
 ^ c 
 
 
 <U C O, 
 
 w =2 2 
 
 
 c c 
 
 
 ll 2 l 
 
 ** 
 
 
 S.8 
 
 
 
 Hil 
 
 
 ^ s 
 
 500 Ib 
 
 50 yards 
 
 100 yards 
 
 
 50 \ ards 
 
 1000 ' ' 
 
 75' 
 
 150* 
 
 
 75 ' 
 
 1 ton 
 
 100 
 
 200 
 
 
 100 
 
 2 
 
 102 
 
 200 
 
 215 yards 
 
 120 
 
 3 
 
 105 
 
 200 
 
 235 * ' 
 
 140 
 
 5 .... 
 
 110 
 
 200 
 
 265 ' 
 
 175 
 
 10 
 
 120 
 
 250 
 
 330 
 
 250 
 
 20 
 
 140 
 
 400 
 
 460 ' 
 
 400 
 
 25 
 
 150 ' 
 
 475 
 
 525 ' 
 
 475 ' 
 
 5 The Manufacture of Explosives, vol. ii., p. 375. 
 
 6 Ibid p. 373. 
 
84 TRANSPORTATION, STORAGE AND HANDLING. 
 
 In an explosion near Chicago in 1886, the magazine 
 containing 50 tons of black powder and 15 tons of dyna- 
 mite, the brick and stone were thrown a distance of 1300 
 feet. This explosion was caused by a stroke of lightning. 
 Greater safety may be obtained by either so placing a 
 magazine that a hill or rise of ground is interposed be- 
 tween it and adjoining objects that may suffer from an 
 explosion. If this is not possible a mound of earth or 
 sand from 12 to 15 feet high, with its base 20 feet from 
 the magazine, will deflect the force of the explosion 
 upwards and will materially shorten the radius of danger 
 in that direction. 
 
 For gunpowder the magazine should be fitted up with 
 racks so that the kegs may be maintained in a slightly 
 inclined position. Dynamite should be stored in tiers, 
 box on box, with battens or lath between the successive 
 layers of boxes to insure good ventilation and to lessen 
 the danger from friction. 
 
 Gunpowder in unopened cases, dynamite in unopened 
 boxes, and fuse securely boxed may be stored together 
 in the same magazine, but no fulminates in the form of 
 caps or otherwise, or loose coils of fuse should ever be 
 stored in the same building with gunpowder and high 
 explosives. 
 
 The building must be kept scrupulously clean, and men 
 with nails exposed on the soles or heels of their boots 
 should not enter or work in any magazine. No fire should 
 be permitted in or about such a structure, and smoking is 
 not to be tolerated in the vicinity of explosives. 
 
TRANSPORTATION, STORAGE AND HANDLING. 85 
 
 It is advised by those having most experience in the 
 storage of explosives that gunpowder kegs should be rolled 
 over once every two or three weeks to prevent caking, 
 and that cases of dynamite should be turned over once 
 every two weeks. According to Mr. G. G Turner, one 
 of the most experienced men in practical blasting opera- 
 tions in America, this is an economy, because it tends to 
 keep the dynamite homogeneous in composition, so that it 
 detonates better. This is not necessary while the dyna- 
 mite remains frozen. 
 
 No keg of gunpowder, or box containing any other 
 explosive, should ever be opened in the magazine. This 
 may be allowed only in small buildings kept for this pur- 
 pose, where a limited supply for immediate use is main- 
 tained. In such a building not over 200 Ib. of any form 
 of explosive should be kept at a time. The kegs or canis- 
 ters of gunpowder should always be kept closed, after 
 removing that needed for use. In the case of dynamites, 
 it is best to unpack the total quantity at once, wipe off 
 the sawdust, lay the cartridges on their sides upon planed 
 board shelves, and then carefully remove all fragments of 
 the original boxes and sawdust, which should be burned 
 in the open. Such sawdust usually contains more or less 
 nitroglycerine, unless the dynamite is in unusually perfect 
 condition. Any oily stain on the cases indicates that 
 nitroglycerine had leaked from the cartridges. The 
 shelves must also be frequently inspected, and if any oily 
 stain is observed, no matter how minute, it must be thor- 
 oughly washed with a saturated solution in water of 
 
86 TRANSPORTATION, STORAGE AND HANDLING. 
 
 ordinary carbonate of soda (sal soda, or *' washing soda "). 
 This destroys the nitroglycerine. The floor of this build- 
 ing should also be washed occasionally with such a solu- 
 tion. No fire of any kind should ever oe permitted in 
 this structure, but it may be warmed by steam pipes, 
 provided the pipes are so placed that no explosive may 
 ev r come into direct contact with them. 
 
 The taking of unopened boxes of dynamite into a mine 
 is a most reprehensible practice, since proper cleanliness 
 and the removal of the sawdust and fragments of the 
 boxes is not so easy as it is from buildings above ground. 
 Only dynamite cartridges from which the sawdust has 
 been wiped and placed in clean boxes should be sent below. 
 
 The characteristics of good dynamite and gunpowder 
 have been given in a previous chapter. It is always ad- 
 visable, on receiving a fresh consignment of such explo- 
 sives, to make an inspection to ascertain that it is in good 
 order. The opening of one box or keg out of every ten 
 will usually suffice to detect any serious deficiency. If 
 not in good condition the manufacturers should be notified 
 at once. If faulty it should then not be returned (for its 
 shipment under such circumstances, especially in the case 
 of nitroglycerine powders, is dangerous), but should be 
 destroyed. For this purpose select a sufficiently isolated 
 situation, and lay the dynamite cartridges on the ground, 
 end to end in a line or very open spiral. Pour paraffine 
 oil over the entire train, or if this is not available use 
 kerosene, and ignite one end of the train with an ordinary 
 fuse (of course not using a cap). It will burn quietly and 
 
TRANSPORTATION, STORAGE AND HANDLING. 87 
 
 safely. In cities where spent lime from gas purifiers is 
 available, this may be used for the destruction of the 
 nitroglycerine in the dynamite, though its decomposition 
 is most readily accomplished with yellow ammonium sul- 
 phide. 
 
 Fuse in open coils should be stored separate from all 
 other explosives, as should also be done with caps, deton- 
 ators or exploders. They should be kept in a dry place, 
 where there is freedom from fire or high temperatures. 
 
 THAWING DYNAMITE. 
 
 Dynamite should not be thawed by direct heat from -a 
 fire or a stove. There is also more or less peril of produc- 
 ing leakiriess and starting decomposition by bhawing it in 
 the sun. There is peculiar peril from thawing it in the 
 sun when the rays are transmitted through window glass, 
 as imperfections in the glass are apt to focus the heat at 
 certain points. 
 
 There are only two safe ways to thaw dynamite, viz., 
 in a room heated by steam pipes, in which case the explo- 
 sive must never be laid on the pipes, and in a vessel sur- 
 rounded by warm water. The proper temperature of the 
 water is 125 F., which is approximately the temperature 
 at which the bare hand can just be held without pain. The 
 water should be heated separately and poured into the 
 water-space in the thawer, and the thawer should not be 
 heated over a stove or other source of heat. 1 he best 
 material to use in making a thawer is sheet zinc, though 
 the best grades of galvanized iron will do. All seams 
 should be absolutely smooth, so as to leave no crevices for 
 
88 
 
 TRANSPORTATION, STORAGE AND HANDLING. 
 
 the lodgment of dirt and nitroglycerine. There are two 
 forma of thawers made, one resembling a glue pot, or the 
 farina boiler used in kitchens. The water space should 
 be at least two inches wide between the inner vesse con- 
 taining the dynamite and the outer wall of the vessel 
 holding the water. In some, the water vessel has an ad- 
 ditional space in the outer wall for an asbestos lining to 
 conserve the heat. A better form of thawer is one con- 
 taining horizontal tubes large enough to receive the car- 
 tridges, the tubes extending through a square or rectangu- 
 lar water box. The water is poured in through a funnel 
 mouth at the top, and drawn off through a faucet below. 
 The advantage of this thawer is that the cartridges lie 
 flat, so that there is less tendency to disturb the hom- 
 ogeneity of the dynamite. 
 
 Fig. 2. 
 
 A third form which is recommended by Mr. Brainerd 
 of the Hamilton Powder Co. for thawing large quantities 
 of dynamite at a time consists of a barrel B (Pig 2) 
 
TRANSPORTATION, STORAGE AND HANDLING. 89 
 
 into which is fitted a pipe system p, with an expansion 
 pipe E, containing water. This pipe system passes 
 through a wall w, and the water in it is heated by a fire 
 or stove at F. The barrel is filled with water, which is 
 heated by the hot water circulating in the pipe system. 
 A zinc or galvanized receptacle, c, for the dynamite, is 
 suspended in the barrel. 
 
 In using any form of thawer the cartridges should be 
 free from sawdust, and the vessel or tubes holding them 
 should be kept scrupulously clean. The only way to make 
 sure of maintaining a proper freedom from accumulations 
 of nitroglycerine in the thawer is to wash it out after each 
 thawing with a strong solution of carbonate of soda (sal 
 soda, or washing soda), which is best applied warm. 
 
 Dynamite is never properly thawed while it feels lumpy 
 at any part of the cartridge. It should be uniformly 
 pliable throughout. Its use when but partially thawed is 
 attended with danger in loading, and its detonation will 
 be imperfect, with the consequent disadvantages of yield- 
 ing a less powerful effect and giving off noxious fumes. 
 
CHAPTER V. 
 
 BLASTING. 
 
 The subject of blasting has been very exhaustively and 
 scientifically treated by Messrs. A. W. and Z. W. Daw, 
 in a book designed for technical men. * A simpler treatise, 
 with good practical suggestions, has been prepared by 
 Oscar Guttmann. 2 There are few operations in mining 
 where a workman can display a higher degree of skill and 
 effect larger economies than in the proper placing of 
 bore-holes, and in the proper adjustment of his charges to 
 the work to be done. Against every hole fired is charged 
 a number of expenses, to wit, labor, power (steam or air) 
 where machine drills are used, wear and tear on plant, 
 explosives, and also a general loss distributed among 
 many items in the operation of the mine, if the output 
 per mirier falls below the estimated average, for the 
 handling of which preparations have been made. 
 
 For the most part efficient work in blasting is a matter 
 of experience and good j udgment . This cannot be taught 
 in books, but there are some general rules which are 
 fundamental, and in proportion as these are understood 
 and appreciated the work of mining will be conducted 
 with greater system and economy. Unsystematic effort 
 
 1 The Blasting of Rock in Mines, Quarries, Tunnels, etc. New York, 
 Spon and Chamberlain, 1898. 
 
 2 Blasting: : A Handbook for the use of Engineers and others engaged in 
 Mining. Philadelphia, J. B. Lippincott Co., 1892. 
 
 [90] 
 
BLASTING. 91 
 
 is always wasteful and costly, and system implies the 
 recognition of some definite principles according to which 
 the work is laid out and prosecuted. 
 
 A few points of prime importance which should be 
 observed are the following : First, the strength and 
 quantity of the explosive should be properly proportion- 
 ed to the cohesive strength or resistance of the rock. 
 
 Second, the " burden," or line of least resistance (i. e., 
 the shortest line that can be drawn from the charge in the 
 bore-hole to the outer free tace of the rock,) should bear 
 a proper relation to the strength of the explosive and to 
 the resistance of the rock. 
 
 Third', if the working face of the rock is so blasted as to 
 leave two or more free faces instead of one for future 
 blasts, the power required to overcome the resistance of the 
 rock will be reduced, and explosives can be economized. 
 
 Fourth, a seam or fissure is a valuable aid in blasting 
 if the hole is so located as to take advantage of this weak- 
 ness, and, on the other hand, the power of the explosive 
 may be expended along such a seam without doing useful 
 work if the hole is improperly located. 
 
 Fifth, breaking to regular benches and faces is more 
 economical than irregular breaking, because the condition 
 of the lock can be more carefully observed, admitting of 
 a more intelligent placing of subsequent bore- holes, and it 
 facilitates the handling and setting up of machine drills. 
 It is also more convenient for work by hand drilling, in 
 addition to which it keeps the mine in better condition 
 for a complete and economical extraction of the ore. 
 
92 BLASTING. 
 
 Sixth, simultaneous firing is more economical in most 
 cases than firing singly or in series, for the reason that 
 the adjacent charges assist each other, reducing the 
 amount of explosive required and the total length of holes 
 to be drilled for any given volume of rock. 
 
 Seventh, careful charging, so as to secure as highly 
 compacted a charge as possible, greatly increases the 
 efficiency of the explosive. 
 
 Eighth, a well prepared primer, in the case of high ex- 
 plosives, is the key to a successful detonation of the 
 charge, on which, other things being equal, its efficiency 
 depends. 
 
 Ninth, the efficiency of all explosives, including high 
 explosives, is dependent to a considerable extent upon 
 the kind, length and degree of compactness of the tamp- 
 ing. 
 
 Tenth, the object of blasting in mines and quarries is 
 to rupture rock so that it may be removed, not to hurl it 
 to a distance, i. e., not to secure wha^ military engineers 
 call " ballistic" effect. Hence only enough explosive 
 should be used to accomplish this. When fragments are 
 thrown more than a few feet by a blast it is generally an 
 evidence that the proper relation did not exist between 
 the charge and the " burden," and that too large a charge 
 was used for the length of the line of least resistance. 
 
 In the accompanying illustration (Fig. 3) B N is the bore- 
 hole ; w L, measured from the centre of the charge in the 
 shortest possible line to the free face, is the line of least 
 resistance, or " burden;" MN is the charge in the bore- 
 
BLASTING. 
 
 93 
 
 hole, which should be about 12 times as long as the di- 
 ameter of the hole at its bottom ; R s K is the outline of 
 the new face which will be 
 produced after the blast. The 
 best results are obtained when 
 the line of least resistance is 
 perpendicular to the line of 
 the bore-hole. The line of 
 least resistance must be short- 
 er than the bore-hole, else 
 the force of the explosion will 
 expend itself in the direction 
 of the' bore-hole If black 
 powder is used in such a case 
 the charge will blow out the 
 tamping, producing a " pop 
 shot. " If high explosives are 
 used in this case the " crater," 
 or funnel of rupture, will have very steep sides and a rela- 
 tively small volume of rock will be ruptured. 
 
 K 
 
 r 
 
 Fig. 3. 
 
 The forces to be overcome vary with the kind of rock, 
 the number and position of the free faces, and the direc- 
 tion of the blast. The direction of the blast is determined 
 by the direction of the line of least resistance. If this is 
 upwards the explosion must overcome the cohesion of the 
 rock plus the weight of the volume of rock ruptured. If 
 downwards, the explosion has to overcome only the co- 
 hesive strength of the rock. A somewhat smaller charge 
 may consequently be used. For each individual shot this 
 
94 BLASTING. 
 
 difference is trifling, but in the aggregate it is an important 
 quantity in practical operations. The rupture of rock in 
 blasting is mainly accomplished by "shearing." The shear- 
 ing strength of close grained granites varies from about 
 2,200 Ib. to 2,900 Ib. per square inch, and of marbles from 
 1,100 Ib. to 1,600 Ib. per square inch. As the total surface 
 sheared by an ordinary blast is often as much as 73 square 
 feet, or more, it will be seen how great is the difference 
 in the resistance to be overcome in different cases, and 
 that no mere "rule of thumb'' method may be economi- 
 cally adopted for determining the charges. It is wasteful, 
 and at best inaccurate, to continue experimenting unsys- 
 tematically with different sizes of charges in any given 
 rock to ascertain approximately the i ight one. It is better 
 to go about it methodically. For this purpose it is 
 necessary first to ascertain what is known as the 4 ' rocF 
 coefficient." This coefficient is the quotient obtained by 
 dividing the weight in pounds of the charge found capable 
 of j ust rupturing the rock by the cube (or third power) 
 of the length of the line of least resistance used in the 
 experimental blast. As the resistances vary with the 
 number of free faces, it is best to determine the rock co- 
 efficient separately for the different conditions in practical 
 work. For example, if a tunnel is to be driven the con- 
 ditions will be as follows : With each new " cut " there 
 will be a certain number of "bearing in" shots to 
 " unkey " the face. In this case the coefficient should be 
 determined for the rock with one free face. The " enlarg- 
 ing shots," after unkeying, will have two, and in some 
 
BLASTING. 
 
 95 
 
 cases three free faces. It will suffice to determine the 
 co-efficient in these cases for the rock with two free faces. 
 The method to be pursued will be sufficiently explained by 
 describing the procedure for obtaining the rock coefficient 
 with two free faces. 3 Select a bench of the rock in which 
 blasting is to be conducted, about two feet wide on top 
 and three feet high. In this drill four or five holes of the 
 diameter to be adopted in regular work in future, 
 three feet deep, so that 
 the line of least resistance 
 will in each case be two 
 feet long. The holes should 
 be bored as far apart as 
 three times the length of 
 the line of least resistance, 
 so that the shots will not 
 influence each other by open- ~* 
 ing up seams. The rock must be 
 
 f- Z 
 
 2 FT. 
 
 i 
 
 Fig. 4. 
 
 selected where it is 
 homogeneous, so that all the shots will be fired under 
 exactly similar conditions. Now charge the several holes 
 with different weights of the explosive, beginning with a 
 quantity so small as not to effect rupture, and increasing 
 by regular amounts to a charge which will be more than 
 sufficient. Select the blast which has produced the de- 
 sired effect as the one by which to determine the coefficient. 
 If this hole was charged with f Ib. (0.625 lb.)of dynamite, 
 
 5 This gives what Daw calls the charging coefficient. Daw's method 
 is more scientific, determining the rock coefficient and charging coefficient 
 separately, but is not so easily applicable by the common miner. The 
 method here given leads to sufficiently accurate results in practical work. 
 
96 BLASTING. 
 
 then the rock coefficient is ' = 0.0781. The charge to 
 
 be used in future blasts is found by multiplying the cube 
 of the length in feet of the line of least resistance 
 by this coefficient. For instance, in this rock, a 
 line of least resistance 2f feet long would require 
 2.753 (=20.797) x 0.0781 =1.624 lb. of dynamite. As the 
 specific gravity of well-compacted high-grade dynamite is 
 about 1.6 (giving 0.057611), per cu. in.), and as the bore 
 hole has a diameter of 1J inch, the charge will occupy a 
 length of 1.25 feet in the hole. This is approximately cor- 
 rect also as to the length of charge in the bore-hole, which 
 should have been 1.5 x 12 = 18 inches. Guttmann 
 recommends that when there are more than two free faces 
 the proper charge will be the following : 
 
 For three free sides, of the calculated charge. 
 " four " \ " 
 
 " five " 2-5 
 
 " six " ^ 
 
 The economy in simultaneous firing will vary with the 
 strength of the rock, but on an average it may be said to 
 save about 25 per cent, of explosive. The economy of 
 boring, under the best conditions, will amount to about 
 24 per cent. This depends on the distance apart of the 
 bore-holes. For very strong compact rock the distance 
 between holes in simultaneous firing should be at least 
 twice the length of the line of least resistance ; for aver- 
 age strong rock, 1J to 2 times ; for moderately strong rock, 
 from the same length as the line of least resistance to 1^ 
 
 4 This last is the case presented in "block-holing," or blasting isolated 
 blocks needing but one charge. 
 
BLASTING. 
 
 times that distance ; and for weak rock only the length of 
 the line of least resistance. 
 
 The lines of least resistance should be proportional to 
 the diameter of the bore-holes. The following table is 
 given by M. Eissler : 
 
 
 DIAMETER OF BORE-HOLES. 
 
 No. 
 
 H in. 
 
 liin. 
 
 If in. 
 
 
 Lines of Least Resistance. 
 
 1 . 
 
 Sift. 
 
 4 ft. 
 
 5ft. 
 
 2 
 
 3f ft. 
 
 5 ft. 
 
 6ft. 
 
 3 
 
 5 ft. 
 
 6ft. 
 
 7 ft. 
 
 The corresponding depths of bore-holes in the above, as 
 stated by Eissler, are, for No. 1, equal to the line of 
 least resistance ; for No. 2, 1J times that length, and for 
 No. 3, twice that length. 
 
 CHARGING HOLES WITH DYNAMITE. 
 Instructions have been given under Fulminates and Fuses 
 (Chap. II.) for attaching the cap and fuse, or electric 
 detonator, to cartridges. The cartridge thus prepared is 
 called the " primer." The several cartridges constituting 
 the charge are inserted first, and care must be taken to 
 have the bore-hole of such a size that they may pas 
 freely to the bottom without binding. It should never 
 be necessary to force them to the bottom. In order 
 
98 BLASTING. 
 
 that they may be compressed to fill the entire width of 
 the hole the cartridge paper must be cut lengthwise. 
 This is best done with a copper blade. To do so with a 
 steel knife is not unattended with danger. The cartridges 
 should now be firmly compressed with a wooden rammer, 
 but they must never' be rammed Firm pressure only 
 is allowable. No steel or iron instrument must ever 
 be used in charging any kind of explosive in a bore-hole. 
 The cartridges must be so well compressed upon each 
 other that no air spaces may remain between them. This 
 would produce an air cushion, and if it did not cause a 
 portion of the charge to escape explosion, would at least 
 prevent perfect detonation, weakening the effect of the 
 explosive. The primer is inserted last. The cartridge 
 paper, as previously explained, should be tied firmly 
 above the cap with a string, one end of which should be 
 long enough to admit of lowering the primer into the .hole 
 with it To lower the cartridge by the fuse or wires is apt 
 to loosen the cap, and thus an air cushion will be formed 
 below it, reducing the power of the explosion. Careless- 
 ness in regard to this simple detail is one of the commonest 
 causes of waste in the use of dynamite. The primer must 
 never be compressed or rammed upon the charge. The 
 "tamping" is now put in. Many writers advocate the 
 use of sand or water with dynamite in holes inclining 
 downwards. The most experienced blasters, however, 
 state very positively that better results are always obtained 
 by using the same clay tamping as is required with black 
 powder. Tamping should be absolutely free from gritty 
 
^BLASTING. 99 
 
 particles. The best material is clay, damp enough to 
 merely retain its form when compressed into a ball in the 
 hand. Pellets of this should be dropped into the hole 
 and very lightly compressed with a wooden rammer until 
 about six inches of the hole above the charge has been 
 filled. From this point to the top the tamping may be 
 more firmly compressed, but not rammed. 
 
 CHARGING HOLES WITH BLACK POWDER. 
 After removing the sludge, dry the hole with a wisp of 
 hay, or a rag, or cotton waste, fastened to the end of a 
 rod. Now pour in the powder through a copper or tin 
 funnel with a long stem, so that the powder will r,ach the 
 bottom of the hole without touching its sides above the 
 limit of the charge. If the hole is horizontal a long scoop 
 may be used, filled with powder, which at the end of the 
 hole is turned round to deposit the charge. For either 
 horizontal holes, or those inclined upwards, the powder 
 may be put into small paper bags and closely pressed into 
 the end. For wet holes waterproof cartridges must be 
 made, as explained in Chapter II. The fuse is now 
 put into place, and in the case of holes filled with powder in 
 bags the last bag should have the fuse tied into it. Dry 
 clay is now pressed over the charge, followed by the 
 ordinary damp clay tamping, pressed firmly for three 
 inches, after which it may be rammed by tapping the end 
 of the tamping stick with a hammer. In holes one inch 
 in diameter the charge will not blow out 7 inches of good 
 tamping. With a diameter of two inches, 18 inches of 
 tamping will not blow out. With a diameter of three 
 
100 BLASTING. 
 
 inches, 20 inches of tamping will not blow out. These 
 are the lowest limits admissable. An excess should always 
 be given. The amount of the charge has nothing to do 
 with it. The determining factor is the diameter of the 
 hole. " Expansion tamping," so called, is employed with 
 black powder when it is desired to cause its action to be 
 retarded so as to split the rock along lines of weakness 
 without shattering. It is consequently of value in quarry- 
 ing. This consists in filling several inches of the hole 
 above the charge with hay, straw, or tow, after which 
 several inches of damp clay tamping are lightly compressed 
 upon it, followed by firmly compressed tamping to the 
 top. By "reaming" the holes so that a V notch is cut 
 on each side the entire length of the hole, making the 
 vertices of the angles of all the V notches lie in a straight 
 line, as shown in Fig. 5, a perfectly homogenous reck 
 may be split with 
 extreme accur- * ~O- O O O O -}B 
 
 acy in any direc- 
 tion, using ex- 
 pansion tamp- Fig. s. 
 ing. Very small charges, of one to three ounces, 
 will do astonishingly effective work under such cir- 
 cumstances. This is known as the Knox system. 
 The use of the " needle " or 4< pricker " is so undesirable 
 that no description of it will be given. The " barrel," or 
 tube, may be used where the hole is wet. A copper tube 
 is slipped over a wire, and the two are inserted together 
 into the hole ; the tamping is compressed around the 
 
BLASTING. 101; 
 
 tube, and the wire is then withdrawn, being replaced 
 by the fuse. The tube is recovered after the blast. 
 For electric firing of black powder low-power fulmin- 
 ating caps are employed. It is erroneously stated by 
 many that the power of the black powder is increased by 
 the use of the fulminating cap, i. e., that it is detonated. 
 Under special conditions it is claimed that gunpowder can 
 be detonated, but it is even questionable whether true 
 detonation is accomplished when the gunpowder has 
 absorbed some nitroglycerine, though apparently in the 
 Judson powder this result is reached. Consequently 
 there is no advantage in the use of strong detonators with 
 common black powder. 
 
 Double primers, that is, two primers in one charge of 
 high explosives, are advocated by some, when firing by 
 electricity. In this case the first primer is placed at the 
 bottom of the charge, and the subsequent cartridges care- 
 fully compressed upon it. This practice is not to be 
 recommended except when carried out by men of the best 
 experience. 
 
 MlS-FlRES. 
 
 A constant source of danger arises from holes which 
 have missed fire. Never be in a hurry to examine such a 
 hole under any circumstances. When the firing is done 
 by electricity, a half hour should be allowed ; when with 
 fuse, wait several hours. It is best then to loosen up the 
 fuse if possible, retreat quickly, and wait again a few 
 minutes. If no explosion occurs, then proceed to with- 
 draw the tamping with a copper or wooden spoon. Never 
 
102 BLASTING. 
 
 use iron or steel for this purpose. In the case of high ex- 
 plosives, or of black powder which had been primed with 
 a cap or detonator, remove the tamping to within about 3 
 inches of the charge, and no closer. Then recharge above 
 this with a large charge of dynamite, and detonate in the 
 ordinary way. If black powder and fuse had been used, 
 withdraw all the tamping, recharge above the old charge, 
 and fire. If dynamite is available, except in quarrying 
 blocks, where this procedure might entail losses of valu- 
 able stone, it is safer to explode such a missed hole of 
 black powder with a dynamite primer, which must not be 
 compressed before firing. In general the use of two 
 kinds of explosive in the same hole is a practice to be 
 most strenuously condemned. 
 
 ADAPTATION OF EXPLOSIVES. 
 
 Adaptation of explosives to the kind of work to be done 
 is of the utmost importance. Dynamites are not suitable 
 for quarrying except where rubble is being obtained. Only 
 the lowest power (40 per cent. ) should then be used. Black 
 powder is the best material for quarrying, although it is 
 claimed that the lower power of joveite develops its ex- 
 plosive effect with sufficient slowness to be adapted to 
 such uses. Also for certain ores, which contain galena 
 and other minerals which may be too highly pulverized by 
 high explosives, a slow acting powder is essential. High 
 explosives pulverize and shatter ; black powder fractures. 
 The higher the power of the dynamite the larger is the 
 sphere of pulverization. For railroad work, and for 
 " dead work " in mines, such as shaft sinking and tunnel 
 
BLASTING. 103 
 
 driving, it is advantageous to use the higher grades of 
 powders, such as 60 per cent, and 75 per cent, dynamites, 
 and their equivalents in other forms of high explosives. 
 
 CHAMBERING. 
 
 The bore-holes we have been considering are round, and 
 slightly tapering toward the bottom. These are suited to 
 blasting in homogeneous rock. In tough material, such 
 as highly kaolinized felspathic rocks, or in clay banks, and 
 in rocks which are extensively cross- fissured (e.g., many f el- 
 sites) in which latter the gas pressure from the explosion is 
 partly relieved by merely expanding the seams or fissures, 
 it is necessary to employ larger concentrated charges 
 instead of the ll extended charge " of an ordinary bore- 
 hole. The commonest method of chambering, or making 
 an enlarged cavity, is to detonate in the end of the hole 
 a small charge of 60 per cent, or 75 per cent, dynamite, 
 using a treble-force detonator, and no tamping. Into the 
 chamber thus produced the charge is filled in the regular 
 way. In the case of short fissured rocks this method 
 often fails. It is then necessary to enlarge the cavity with 
 a special tool, called an expanding bit, made for this pur- 
 pose. 
 
 BANK BLASTING. 
 
 Bank blasting is practised in breaking up large masses 
 of more or less firmly cemented gravel in hydraulic min- 
 ing, so as to admit of washing it out with a monitor. For 
 this purpose black powder and Judson powder are most 
 commonly employed, Although any slow powder will serve, 
 
104 BLASTING. 
 
 as much as 50,000 Ib. being sometimes exploded in one 
 blast. From 10 to 20 Ib. of black powder are required for 
 each 1,000 cubic yards of gravel. Although the method 
 must be adapted to the local conditions, it may be said in 
 general that a drift should be run in at the bottom of the 
 bank, with a length equal to the height of the bank, 
 or a shaft should be sunk ab a distance from the 
 edge of the bank equal to its height. A cross drift is then 
 driven at the end of this excavation, forming a T, the 
 cross of the T being also of the same length as the height 
 of the bank. Kegs of powder are then piled upon each 
 other in each end of the cross drift, every tenth keg hav- 
 ing its head removed. A train of kegs, with the heads 
 off, are placed in the drift to its center, where the primer 
 is located, or a dynamite primer may be inserted in each 
 keg in the train, all connected in series for instantaneous 
 electric firing. When a single central primer is used, it 
 consists of a box into which about 200 Ib. of powder are 
 placed, with several dynamite primers inserted into it, 
 their detonators being connected in series for firing. The 
 space above the large primer is now tamped tightly with 
 debris, and the leading wires are laid to the surface. The 
 drift or shaft is now tightly filled with clay and gravel, so 
 as to make a firm tamping. The charge is then fired by a 
 powerful battery. 5 
 
 5 For further details on this subject see "A Practical Treatise on 
 Hydraulic Mining," by A. J. Bowie ; New York, D. Van Nostrand Co., 1889, 
 and a paper on the Simultaneous Ignition of Thousands of Mines, by Julius 
 H. Striedinger, in the Transactions of the American Society of Civil Engi- 
 neers, New York, June, 1877. 
 
BLASTING. 
 
 105 
 
 LOCATING BORE-HOLES. 
 
 The general principles governing the placing of shot- 
 holes have already been stated. It only remains to 
 explain the method of procedure in special cases. In 
 blasting to benches in homogeneous massive (i.e. unstrati- 
 iied) rock, the bore-hole should be exactly as long as the 
 intended height of the bench. If the charge, the diame- 
 ter of the hole and the line of least resistance are pro- 
 perly proportioned, the rock will break in an approximately 
 perfect bench form. If the rock is stratified (Fig. 6), 
 the hole should be 
 bored short of the 
 bedding "plane c D. 
 The force of the ex- 
 plosion will tend to 
 relieve itself along 
 this plane ; hence 
 the length of the 
 charge in the bore- 
 hole must be pro- 
 portioned to the Q 
 relation subsisting 
 between the thick- 
 ness of the stratum 
 and the length of line of least resistance. The diameter 
 of the hole, as shown before, depends upon its length. 
 The reduction in the length of the charge, M, calculated in 
 the ordinary way, is regulated as follows, T being the thick- 
 ness of the stratum, M the calculated length of charge, M^ 
 
 
 
 f 
 
 
 
 
 h 
 
 
 
 k- w * 
 
 IH 
 
 
 1 
 
 
 J J, 
 
 D 
 
 Fig. 6. 
 
100 BLASTING. 
 
 the reduced length, and w the line of least resistance'' 
 
 When t w m { = Jm. 
 
 " t=l|w nu=m. 
 
 " t=2 w 1111=111. 
 
 In shaft sinking or tunnel driving, if there is a persis- 
 tent joint, or seam, advantage can be taken of it for the 
 " unk eying" or " breaking-in " shots. These can then 
 be set deeper, so as to break out a "key" to the full 
 depth of each cut, with a minimum of explosive. This is 
 a " side cut." A side cut can be used where there is no 
 seam or wall to shoot to, but it offers no particular 
 advantages. In homogeneous rock the " center cut," 
 either the square or the V-cut, is most commonly adopted. 
 
 The square center cut is shown in Fig 7, the small 
 circles in the plan indicating the commencement of the 
 hole, and the parallel lines the projection of the hole on 
 a plane surface, revealing its position. To further eluci- 
 date this the section on the line A B is given. Hole No. 
 18 does not properly fall on this line, but its relative 
 position as shown is approximately accurate. It will be 
 seen that in this tunnel heading, 6 ft. wide and 7 ft. high, 
 20 holes have been bored, reaching to a distance of 3 ft. 
 3 in. from the face, which is the length of the cut. The 
 44 breaking in " or unkeying shots are Nos. 1, 2, 3 and 4, 
 converging to a point. It is not undesirable if these holes 
 unite, forming one chamber at the point. Thus by means 
 of the concentration of the charge towards and at the 
 
 A.W. and Z.W. Daw. 
 
BLASTING. 
 
 107 
 
 point the large resistance of the rock is overcome, in spite 
 of the somewhat lengthy line of least resistance for blast- 
 ing to only one free 
 face. These must be 
 fired simultaneously 
 The " folio wing" or 
 "enlarging" shots, 16 
 in number, are s o 
 placed as to be fired | 
 in either two or three 
 successive volleys. The 
 plan most economical 
 of powder would be to 
 fire 5, 7, 9 and 11 in 
 the second volley ; 6, 
 8, 10 and 12 in the 
 third, and 13, 14 ; 15, 
 16, 17, 18, 19 and 20 
 in the fourth. Con- 
 di t i o n s , however, 
 might render it more 
 economical to use larg- 
 er charges in holes 6, 
 8, 10 and 12, and in- 
 clude them in the 
 same volley with 5, 7 , 
 9 and 11. All the enlarging shots are breaking to 
 two free faces, being nearly the equivalent of bench 
 blasting, and they all have relatively short lines of 
 
108 
 
 BLASTING. 
 
 least resistance, properly proportioned to the depth of the 
 holes. The last PLAN 
 
 volley serves 
 the purpose 
 of ' ' trimming- 
 up " shots, so 
 that the walls 
 left should be 
 clean and true. A 
 In order to avoid 
 irregularities in 
 the walls it is 
 essential to start 
 these holes as 
 close to the walls 
 as possible, and 
 to give them 
 very little incli- 
 nation from the 
 perpendicular, 
 and then to 
 maintain exactly 
 correct propor- 
 t i o n s between 
 the line of least 
 resistance, the 
 
 diameter of the Fig . 8 . 
 
 hole and the charge used. 
 
 V-SHAPED CENTER CUT. 
 In Fig. 8 is shown the V-cut, which offers two advant- 
 
 SECTION ON A.B. 
 
BLASTING. 109 
 
 ages. There are fewer dry holes to be bored, and the 
 44 key " can be broken out with smaller charges, since 1, 
 2, 3, and 4 are short holes, as appear in the section on 
 A B, the line of least resistance for these being cor- 
 respondingly short. These four constitute the first volley, 
 and provide shorter lines of least resistance for the 
 remaining breaking-in shots, 5, 6, 7 and 8, which make 
 the second volley. The third volley comprises holes 9, 
 10, 11, 12, 13 and 14 ; and the fourth volley, which 
 trims up, includes 15, 16, 17, 18, 19, 20, 2i and 22. 
 
 These will serve as suggestions for economical work 
 under normal conditions in hard homogeneous rock, 
 special conditions requiring suitable modifications. 
 
 The consumption of explosives in practice is found to 
 be approximately as follows : 
 
 For small blasts in open workings, ^ to Ib. of black 
 powder, and ^ to J Ib. of dynamite per ton of rock. 
 
 For large blasts in open workings, J to ^ Ib. of black 
 powder, and % to J Ib. of dynamite per ton of rock. 
 
 For headings, tunnels and shafts, to 2 Ib. of dyna- 
 mite per ton of rock. 
 
 THE LONG-HOLE METHOD. 
 
 Deep bore holes, or the long-hole method, has been 
 adopted in both shaft sinking and in bench blasting, in 
 open cuts and in large stopes. In the case of shaft sink- 
 ing a series of diamond drill holes are bored to the full 
 depth of the shaft, and filled with sand. A sufficient 
 depth is left empty to receive a charge of 75 per cent, 
 dynamite, and the holes are fired simultaneously. Then 
 
110 BLASTING. 
 
 sand is spooned out to make room for another cut, and so 
 on to the bottom Although the line of least resistance 
 coincides with the line of the bore-hole, this disadvantage 
 is offset by the use of the high-power dynamite, and by 
 the great saving of time and cost in drilling. In adapting 
 this method to bench blasting holes are drilled as deep as 
 convenient in parallel rows, filled with sand as before, 
 and successive slices are then blasted off. Where condi- 
 tions render this system capable of adoption it affords 
 highly economical results. 
 
APPENDIX A. 
 
 EXAMPLES or CAUSES or ACCIDENTS. 
 
 The following examples have been selected from the 
 Annual Report for 1898 of the Inspectors of Explosives 
 of Great Britain. 
 
 BLASTING GELATINE. 
 
 About 1 Ib. being thawed in a tin over a 
 watchman's fire 1 
 
 A quarry man carrying cartridges and de- 
 tonator in the same hand 
 
 Four holes had been charged, each with a 
 cartridge and primer, and fired in the 
 usual manner. All the shots were 
 heard to go off. In removing the 
 debris an explosion occurred. The 
 gelignite was properly thawed. Sup- 
 posed that one of the primers failed 
 to detonate the charge 
 
 Hole too small for cartridge. Explosion 
 occurred in pressing down the first 
 cartridge with a wooden rammer 
 
 A quarry man forced cartridge into a hole 
 with an iron bar 
 
 Two cartridges put into a hole, and forced 
 down with an iron bar , 
 
 Clearing away debris after a blast. Struck 
 portion of unexploded cartridge 
 
 Pressing cartridge into a hole with a piece 
 of drill steel . 
 
 Killed. Injured 
 
 [m 
 
112 
 
 APPENDIX. 
 
 BLASTING GELATINE. Con. 
 
 Killed. Injured. 
 
 Cartridge vas exploded by ramming into 
 bore-hole. The weather was too cold 
 for this explosive, and it was probably 
 near the freezing point, and hence 
 sensitive 1 
 
 Ramming cartridge with steel drill 1 1 
 
 Deepening a hole which had been fired and 
 
 had not done its work 1 
 
 Block-holing. Charge had failed to go off. 
 Workman returned to relight the fuse, 
 when the explosion occurred 1 
 
 Testing the end of a hole after a blast with 
 an iron bar, to see if any of the charge 
 remained 3 
 
 Testing hole in same manner after a blast 
 
 in a shaft 5 
 
 DYNAMITE. 
 
 Forcing primer into hole with a wooden 
 
 rammer 1 
 
 Miners returned after 20 minutes to investi- 
 gate cause of mis-fire 2 
 
 Ramming in the first ball of tamping clay 1 
 
 GUNPOWDER. 
 
 A hole had missed fire. Two days later a 
 man started driving a wedge near the 
 hole when the charge explodt-d 1 
 
 Using a short fuse to hasten explosion. 
 The charge exploded before the work- 
 man could retreat , , . , I 
 
APPENDIX. 
 
 GUNPOWDER. Von. 
 
 Smoking a pipe while charging a hole 
 
 Loading a hole with the aid of an iron 
 
 stemmer 
 
 Firing a charge in a hole to clear it of 
 
 water, and immediately reloading 
 Powder lodged in a seam of rock in a 
 
 quarry. Accidentally ignited 
 
 Ramming charge in hole with an iron crow 
 
 bar 
 
 Drilling out a mis-fire shot with a blunt 
 
 drill 
 
 Tamping a charge with an iron bar 
 
 Forcing a cartridge into too small a hole 
 
 113 
 
 Killed. Injured. 
 
 DETONATOBS. 
 
 Attempting to withdraw a wire from an 
 electric detonator 
 
 Attaching a fuse to a detonator carelessly. 
 
 Detonator found in debris. Tapped it to 
 see if it was good 
 
 Trying to destroy a detonator by striking 
 it with a stone 
 
 Holding an electric detonator in a g 
 flame .' 
 
 Trod on a detonator. Exploded 800 other 
 
 detonators in the same room 2 
 
 Pricking the composition in the detonator 
 with a pin 
 
 Spark from miner's lamp fell into box con- 
 taining fuse and caps 1 
 
114 
 
 APPENDIX. 
 
 ACCIDENTS IN THAWING DYNAMITE. 
 
 Killed. Injured. 
 
 Some cartridges being thawed on a stove 
 
 in the weigh-house , 2 
 
 Thawing cartridges in front of a kitchen 
 
 fire 1 
 
 Thawing dynamite on a shovel 
 
 Cartridges placed near a fire to thaw .... 2 
 
 Cartridges placed in an oven to thaw 1 
 
 Hot-water thawer containing dynamite 
 
 placed on blacksmith's fire 1 
 
 Thawing dynamite wirh a candle 
 
 Warming dynamite over blacksmith's fire . 2 
 
 Thawing dynamite in water over a fire .... 2 
 
 Heating dynamite in a tin over a candle . . 1 
 Reheating some water which had been used 
 
 in a dynamite thawer, 3 accidents .... 2 
 
 Six similar explosions recorded : . . . . 6 
 
 Rubbing cartridge in hands to complete 
 
 thawing 
 
 Thawing dynamite over a candle, 2 accidents 1 
 Cartridge left in pocket of trousers which 
 
 were hung before fire to dry 1 
 
 Total number of accidents from thawing for 
 
 1898 was 81, the casualties being 68 
 
 All other accidents, 194 52 
 
 Totals . 120 
 
APPENDIX. 
 
 115 
 
 The accidents from explosives reported in Ontario for 
 1899 are as follows : 
 
 DYNAMITE 
 
 Killed. Injured. 
 
 Forced cartridge into too small a hole, or 
 used iron pipe as tamping rod 
 Drillin^ in or near missed hole . 
 
 1 
 3 
 
 
 Charged hole, lit fuse, went short distance, 
 came back and shoved piece of wood in 
 hole just as charge exploded 
 
 
 1 
 
 Thawing dynamite before open fire in 
 blacksmith's forge 
 
 1 
 
 1 
 
 
 
 
 Totals 
 
 5 
 
 2 
 
 
 
 
 APPENDIX B. 
 
 IMPORTANT BOOKS ON EXPLOSIVES. 
 
 Blasting : A Handbook for the Use of Engineers and 
 Others Engaged in Mining, Tunnelling, Quarrying, 
 etc. Oscar Guttmann. Philadelphia : J. B. Lippin- 
 cottCo., 1892. 
 
 Blasting of Rock in Mines, Quarries, Tunnels, etc. A. 
 W. and Z. W. Daw. New York : Spon and Chamber- 
 lain, 1898. 
 
 Explosives and their Power. M. P. E. Berthelot. 
 Trans, from the French by Napier Hake and William 
 McNab. London : John Murray, 1892. 
 
 Explosifs Modernes. P. F. Chalon. Paris : E. Bernard 
 etCie., 1889. 
 
 Geschichte der Explosivstoffe. S. J. von Romocki. 
 Two volumes. Berlin : Robert Oppenheim, 1895. 
 
116 APPENDIX. 
 
 Handbook of Modern Explosives. M. Eissler. London: 
 Crosby, Lock wood and Son, 1890. 
 
 Index to the Literature of Explosives Part I. Charles 
 E. Munroe. Baltimore : Isaac Friedenwald, 1886. 
 
 ditto. Part II. Baltimore : Deutsch Lithograph- 
 ing and Printing Co., 1893. 
 
 Lectures on Explosives. Willoughby Walke. New York : 
 John Wiley and Sons, 1897. 
 
 Manufacture of Explosives. Oscar Guttmann. Two 
 volumes. London : Whittaker and Co., 1895. 
 
 APPENDIX C. 
 
 REGULATIONS FOR THE STORAGE AND HANDLING OF 
 EXPLOSIVES IN ONTARIO. 
 
 From the Act to amend the Mines Act, 63 V. c. 13. 
 
 3. No magazine of powder, dynamite or other explosive 
 shall be erected or maintained at a nearer distance than 
 four hundred feet from the mine and works, except 
 with the written permission of the Inspector, and every 
 such magazine shall be constructed of materials and in a 
 manner to ensure safety against explosion from any 
 cause, and shall be either so situated as to interpose a 
 hill or rise of ground higher than the magazine between 
 it and the mine and works, or else an artificial mound of 
 earth as high as the magazine, and situated not more than 
 30 feet from it shall be so interposed. 
 
 4. No powder, dynamite or other explosive shall be 
 stored underground in a working mine in excess of a sup- 
 ply for 48 hours, and in no case shall more than 100 
 pounds be so stored on one level. It shall be kept in 
 securely covered boxes, and located in otherwise unused 
 parts of the mine never less than 10 feet from lines of 
 
APPENDIX. 117 
 
 underground traffic, nor less than 150 feet from places 
 where drilling and blasting are carried on, and the tem- 
 perature of such place shall never be less than 60 degrees 
 F. nor more than 125 degrees F. 
 
 5. No fuse, blasting caps, electric detonators or any 
 articles containing iron or steel shall be stored in the 
 same magazine, box or other receptacle with powder, 
 dynamite or other explosive, nor at a less distance than 
 50 feet from such magazine, box or receptacle. 
 
 6. Whenever a workman opens a box containing an 
 explosive, or when he in any manner handles the same, 
 he shall not permit any lighted lamp or candle to come 
 closer than five feet to such explosive, nor permit said 
 lamp or candle to be in such a position that the air cur- 
 rent may convey sparks to the explosive, and a workman 
 shall not approach nearer than five feet to an open box 
 containing an explosive with a lighted lamp, candle, pipe 
 or any other thing containing fire. 
 
 7. A thorough daily inspection shall be made of the 
 condition of stores of explosives in a mine, and it shall 
 be the duty of the manager, captain or other officer in 
 charge of the mine to institute an immediate investigation 
 when an act of careless placing or handling of explosives 
 is discovered by or reported to him ; and any employee 
 who commits a careless act with an explosive or where 
 explosives are stored, or who haying discovered it omits 
 or neglects to report immediately such act to an officer in 
 charge of the mine shall be guilty of an offence against 
 this Act. 
 
 8. A proper apparatus, approved by the Inspector, 
 shall be provided for use in every mine for thawing ex- 
 plosives, and shall be employed under the direction of 
 the mine foreman, 'or of careful and experienced work- 
 men. 
 
118 APPENDIX. 
 
 9. In charging holes for blasting, no iron or steel tool 
 or rod shall be used, and no iron or steel shall be used in 
 any hole containing explosives. 
 
 10. A charge which has missed fire shall not be with- 
 drawn, but shall be blasted ; and in case the missed hole 
 has not been blasted at the end of a shift, the fact shall 
 be reported by the foreman or shift '* boss" to the next 
 relay of miners before work has been commenced by 
 them. To facilitate the blasting of such charge, in cases 
 where the depth of hole and length of charge are known, 
 the tamping may be removed with a copper or wooden 
 instrument to within three inches of the charge in order 
 to insert a new primer for exploding it. 
 
 11. All drill holes, whether sunk by hand or machine 
 drills, shall be of sufficient size to admit of the free inser- 
 tion to the bottom of the hole of a stick or cartridge of 
 powder, dynamite or other explosive without ramming, 
 pounding or pressure. 
 
 12. No powder, dynamite or other explosive shall be 
 used to blast or break up ore in roast heaps where by 
 reason of the heated condition of such ore or otherwise 
 there is any danger or risk of premature explosion of the 
 charge. 
 
 34. All oils and other inflammable materials shall be 
 stored or kept in a building erected for that purpose, and 
 at a safe distance from the powder magazine and from the 
 main buildings, and their removal from said building for 
 use shall be in such quantities only as are necessary to 
 meet the requirements of one day. 
 
INDEX. 
 
 PAGE 
 
 Absorbents for ctynamites 29 
 
 Accidents, causes of Ill 
 
 Adaptation of explosives 102 
 
 Amides 40 
 
 Ammonite 21 
 
 Asphaline .... 16 
 
 Asphyxia from fumes 61 
 
 Atlas Powder 32, 37 
 
 Bank blasting 103 
 
 Barrel. ...*.. 100 
 
 Battery, firing by. . . '. 49 
 
 for firing 50 
 
 " pull-up " 51 
 
 Bellite 19 
 
 Bibliography of explosives 115 
 
 Bickford Fuses 42 
 
 Black powder see Gunpowder 12 
 
 Blasting, ballistic effect t 92 
 
 bank : 103 
 
 bearing-in shots 94 
 
 block-holing. . 96 
 
 books on 115 
 
 bore-holes, locating 105 
 
 . caps see Detonating caps 44 
 
 chambering 103 
 
 charges 96 
 
 charging coefficient ;........ 95 
 
 charging holes 97, 99 
 
 concentrated charges 103 
 
 crater 98 
 
 diameter of bore-holes 97 
 
 [119] 
 
120 INDEX. 
 
 Blasting Continued. PAGE 
 
 double primers 101 
 
 enlarging shots 94 
 
 extended charges 103 
 
 force to rupture 94 
 
 funnel of rupture 93 
 
 gelatine : /. 23, 37 * 
 
 gelatine, accidents with Ill 
 
 general considerations 90 
 
 Knox system 100 
 
 line of least resistance 92, 106 
 
 long-hole method 109 
 
 magneto-machines for 51 
 
 mis-fires 101 
 
 powder 13, 98 
 
 rock coefficient 94 
 
 shearing 94 
 
 simultaneous firing 96 
 
 square centre cut 106 
 
 tamping 98, 99 
 
 unkeying shots 106 
 
 V-shaped centre cut 108 
 
 Block-holing '. . 96 
 
 Bore-holes, diameter 97 
 
 locating 105 
 
 Borlinetto's powder 19 
 
 Brainerd, Dwight 25 
 
 British Explosives Act 11 
 
 Burden in blasting 92 
 
 Caps 44 
 
 Carbo-azdtine, composition of 13 
 
 Carbodynamite 30 
 
 Carbolic acid, nitration of 18 
 
 Carbonite 33 
 
 Castellanos powder 37 
 
 Chambering , 103 
 
 Charcoal for gunpowder 12 
 
 Chlorate mixtures 16 
 
INDEX. 121 
 
 PAGE 
 
 Chlorate of potash 16, 39 
 
 Chlorine in nitro-compounds 22 
 
 Classification of explosives 11, 12 
 
 Cocoa powder 13 
 
 Coefficient, charging 95 
 
 Coefficient, rock 94 
 
 Combustion, products of 58 
 
 Compounds see Explosive 11 
 
 Consumption of explosives 109 
 
 Cotton powder 28 
 
 Danger radius for magazines 83 
 
 Destruction of deteriorated dynamite 86 
 
 Deterrents 32 
 
 Detonating caps 44 
 
 accidents with 113 
 
 attaching to fuse ' 48 
 
 bridge detonators 46 
 
 electric 45 
 
 fixing into cartridges . . 47 
 
 grades 45 
 
 slot detonators 46 
 
 storage '. 87 
 
 fuse 43 
 
 wave velocity 56 
 
 Detonation vs. explosion 54 
 
 of frozen dynamite 35 
 
 of gunpowder 31, 57 
 
 Dopes for dynamites . . 29, 37 
 
 Dualin 33, 37 
 
 Dupre, Dr., on Chlorate Mixtures 16 
 
 Dynamite , 22, 29 
 
 accidents with . ; 112, 115 
 
 adaptation of 102 
 
 characteristics of 34 
 
 charging holes with 97 
 
 consumption of 109 
 
 destruction of 86 
 
INDEX. 
 
 Dynamite Continued. PAGE 
 
 dopes 29 
 
 effect of dampness on 36 
 
 efflorescence 35 
 
 freezing temperature 35 
 
 frozen, explosion of 35 
 
 fumes 69 
 
 gelatine 38 
 
 ignition temperature 35 
 
 inspection 86 
 
 leakiness 35, 38, 85 
 
 storage 85 
 
 tests 35 
 
 thawing 87 
 
 thawing, accidents 114 
 
 transportation See Transportation . 
 
 Electric detonators 45 
 
 firing 49 
 
 firing machines 50 
 
 Emmensite 21 
 
 Exploders 44 
 
 Explosion vs. detonation 54 
 
 Explosive compounds of the nitric-derivative class 22 
 
 of the nitro-substitution class 17 
 
 Explosive, flameless 20 
 
 mixtures of the chlorate class 16 
 
 mixtures of the nitrate class 12 
 
 Explosives, adaptation 102 
 
 books on 115 
 
 liquid 40 
 
 regulations in Ontario 116 
 
 of the Sprengel class * 39 
 
 theory of 52 
 
 transportation 66 
 
 Favier explosives 21 
 
 Firing by battery 49 
 
 explosives ^6 
 
 machines ...,,.,. 50 
 
INDEX. 123 
 
 PAGE 
 
 Flameless explosive 20 
 
 Forcite 38 
 
 Fulminate of Mercury 40 
 
 power of 55 
 
 Fulminates -. . . . 40 
 
 transportation see Transportation 66 
 
 Fulminators see Detonating caps 44 
 
 Fumes 52, 58 
 
 physiological effect of 60 
 
 Fuse 42 
 
 attaching detonators 48 
 
 Bickford 42 
 
 detonating 43 
 
 lighting 49 
 
 premature ignition of charge hy 47 
 
 quick burning 43 
 
 safety 42 
 
 storage 87 
 
 tape 43 
 
 use in firing 46 
 
 Gelatine, blasting 23, 37 
 
 dynamite 38 
 
 Gelbite . 21 
 
 Gelignite 38 
 
 Giant powder 32, 57 
 
 Glonoine 64 
 
 Guncotton 23 
 
 properties of 23 
 
 Gunpowder .. 12 
 
 accidents with 112 
 
 cartridges 47 
 
 charging holes with 99 
 
 combustion products 58 
 
 composition of 12 
 
 detonation 31, 57 
 
 explosion of 15 
 
 ignition temperature 15 
 
 inspection 86 
 
124 INDEX. 
 
 Gunpowder Continued. PAGE 
 
 properties of 14 
 
 specific gravity of 14 
 
 storage * 84 
 
 tests of purity 15 
 
 transportation see Transportation 66 
 
 Hellhoffite 40 
 
 Hercules powder 33, 37 
 
 Horsley powder 33 
 
 Ignition temperature of blasting gelatine 37 
 
 dynamite 35 
 
 guncotton 24 
 
 gunpowder 15 
 
 mercury fulminate 41 
 
 nitroglycerine 25, 27 
 
 Inspection of explosives 86 
 
 lodoamide 41 
 
 Joveite 
 
 Judson R. R. P. powder 
 
 Kieselguhr 29, 30 
 
 Lamm, Carl 19 
 
 Leading wires ; 51 
 
 Leaky dynamite 35, 38, 85 
 
 Lightning, ignition of explosives by 82 
 
 Line of least .resistance 92, 105 
 
 Literature on explosives 115 
 
 Long-hole method of blasting 109 
 
 Lyddite 18 
 
 azines 77 
 
 lightning protection 82 
 
 masonry 80 
 
 neto-machines for firing 51 
 
 Mercury fulminate 40 
 
 destruction of 41 
 
 power of 55 
 
 Mis-fires ... .101 
 
INDEX. 125 
 
 PAGE 
 
 Mixtures see Explosive 11 
 
 Munroe, Dr. Chas. E 10, 31, 54 
 
 Needle 100 
 
 Nitrate class, explosive mixtures of 12 
 
 Nitration 18 
 
 Nitre for gunpowder 13 
 
 Nitrogen chloride 53 
 
 iodide 41 
 
 Nitroglycerine 22, 24 
 
 combustion products 59 
 
 decomposition of 26 
 
 ignition temperature of 25, 27 
 
 physiological effect of 27, 64 
 
 properties of 25 
 
 residual after explosion 63 
 
 uses of 27 
 
 Ontario regulations concerning explosives , . 116 
 
 Penetration of rifle balls 79 
 
 Percussion caps see Detonating Caps 44 
 
 Phenol, nitration of 18 
 
 Physiological effects of Jumes 60 
 
 Picrate of potassium 19 
 
 Picric acid 18 
 
 Potentite 29 
 
 Pricker , 100 
 
 Primer 47, 48, 97 
 
 Products of combustion 58 
 
 Pyrolithe, composition of 13 
 
 Rack-a-rock 39 
 
 Rand, Addison C 10 
 
 Reaming shot-holes 100 
 
 Regulations for storage, etc., in Ontario 116 
 
 Rendrock 33, 37 
 
 Rifle balls, penetration tests 79 
 
 Roburite 21 
 
 Safety explosives 19, 20, 22 
 
 Sawdust for dopes "! 34 
 
126 INDEX. 
 
 PAGE 
 
 Securite 20 
 
 Shooting oil wells 27 
 
 Simultaneous firing 96 
 
 Sodium nitrate in blasting powder 13 
 
 Sprengel explosives 39 
 
 Stonite 32 
 
 Storage, care of magazine 85 
 
 in caves, tunnels, etc 78 
 
 detonating caps 87 
 
 dynamite 85 
 
 of explosives 77 
 
 fuse 87 
 
 gunpowder 84 
 
 Ontario regulations 116 
 
 radius of danger 78, 83 
 
 suitable magazines 78 
 
 Tamping 98, 99 
 
 Tape fuses 43 
 
 Thawing dynamite 87 
 
 accidents 114, 115 
 
 Theory of explosives 52 
 
 Tin nitrate, basic 53 
 
 Tonite 28 
 
 Trichloramide 53 
 
 Tri-nitro cellulose 23 
 
 Tri-nitroglycerine 24 
 
 Transportation of explosives 66 
 
 British law 68 
 
 Dominion of Canada regulations 68 
 
 in mines . ; 67 
 
 Ontario regulations 67 
 
 Pennsylvania R. R. regulations 70 
 
 by wagons 66 
 
 Turner, G. G 48 
 
 Velocity of detonating wave 56 
 
 Vigorite 33 
 
 Volne> powders 21 
 
 Vulcanite 31 
 
 Woodpulp for dopes . . 34 
 
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