344 



EXPLOSIVES. 



by request, a part of the latter is sometimes 

 replaced by potassium or sodium nitrate. This 

 explosive, made both in England and the 

 United States, is valuable on account of the 

 safety with which it can be transported. Po~ 

 tentite, Liverpool cotton-powder, and poten- 

 tite cotton-powder, are names given to a ni- 

 trated gun-cotton compound manufactured in 

 England. Gun-cotton has lately received in- 

 creased attention in consideration of its use 

 in the preparation of the gelatine dynamite. 



Those substances which contain nitro-glycer- 

 in constitute the most important class of the 

 so-called " high explosives." 



Nitro-glycerin, or glonoine, which is consid- 

 ered to be the most powerful explosive known 

 to man, was discovered in 1847 by Sobrero, 

 and first practically applied by A. Nobel in 

 1863. It is made by introducing pure glycerin 

 into a mixture of pure concentrated nitric acid 

 and sulphuric acid, cooled to a certain degree 

 of temperature. It is a light - yellow, clear, 

 oily liquid, odorless, has a pleasant, sweet 

 taste, is poisonous when inhaled, swallowed, 

 or introduced into the body through the pores, 

 producing headache and sickness. Its specific 

 gravity is 1/595 to 1*6 ; it freezes when clear 

 and transparent at about 40 C. When ignited, 

 it quietly burns without refuse, and produces 

 carbon dioxide, water, nitrogen, and hydrogen, 

 all in themselves perfectly harmless. When 

 gradually heated to 180 0., or when acted 

 upon by powerful mechanical forces, by the 

 explosion of certain substances as fulminate of 

 mercury, nitro-glycerin explodes. The gases 

 developed by the explosion occupy 1,250 times 

 the original volume of the explosive, and by 

 the high degree of heat evolved this is again 

 expanded eight times, so that the total expan- 

 sion equals 10,000 times the original bulk. The 

 liquid nitro-glycerin is by itself very little used 

 for explosive purposes, but serves as a base in 

 the manufacture of the high explosives that 

 are sold under various trade-names, but are 

 known generically as dynamite. According to 

 the census, 3,037,722 pounds of nitro-glycerin, 

 having a value of $1,830,417, were manufact- 

 ured in this country during 1880. 



Dynamite is the name given to those explo- 

 sives that contain nitro-glycerin in absorption. 

 Dynamite proper was first brought into gen- 

 eral use in Europe by Nobel, in 1867. The 

 absorbent used was infusorial earth, other- 

 wise known as diatom aceous silica, silicious 

 marl, tripoli, rotten - stone, and commonly 

 called Eieselguhr. In 1868 it was introduced 

 into the United States, and became known as 

 giant powder. The different grades of dyna- 

 mite now made under Nobel's patents are :" 



The absorbent for No. 1 is pure infusorial 

 earth ; a mixture of potassium nitrate, wood- 

 fiber, rosin, soda, and infusorial earth is used 

 for the remaining grades. Dynamite is a pasty, 

 plastic mass, of 1'4 specific gravity, and of a 

 yellowish-red color, unctuous to the touch, 

 and without any odor. It can be exploded by 

 means of a cap or by contact with red-hot 

 metal; or, again, by rapid heating to a high 

 temperature, or by means of a heavy blow or 

 concussion. Brought into contact with a burn- 

 ing match or fuse, it will burn without ex- 

 ploding, similar to damp powder ; hence nitro- 

 glycerin compounds do not explode from the 

 application of fire (unless in large quantities), 

 but by the application of force. This force 

 may be produced from some shock, jar, blow, 

 percussion, concussion, or vibration, or from 

 the heat produced from one of these. That is, 

 force in some form is necessary to cause the 

 detonation of this class of explosives, while it 

 is not essential in the case of gunpowder. The 

 improper use of dynamite has led to stringent 

 laws on that subject in England. During the 

 last session of Congress, Senator Edmunds in- 

 troduced a bill into the Senate to punish all 

 who make, use, or carry dynamite for criminal 

 purposes. The employment of other absorb- 

 ents, in varying proportions, has led to the in- 

 troduction of numerous compounds, with spe- 

 cial names. The most important of these are : 



Dualine, invented by Dittmar, is cellulose, 

 derived from wood-fiber (poplar), nitrated and 

 then saturated with nitro-glycerin. Trauzl 

 gives its composition as nitro-glycerin, 50 

 parts ; fine sawdust, 30 parts ; potassium ni- 

 trate, 20 parts. Sebastin invented by Fahneh- 

 jelm, consists of charcoal produced from a spe- 

 cial wood and prepared in such a manner as 

 to be able to absorb and solidify the greatest 

 possible amount of nitro-glycerin. A small 

 quantity of potassium nitrate is added, to in- 

 crease the rapidity of the explosion. There 

 are two grades : 



Atlas Powder, made in the United States, is 

 similar, and has the following composition : 



Hercules Powder consists of : 



