Nitro-Explosives: A Practical Treatise

Classification of Dy

Dynamite-Other Forms

itable Gun-Cotton for,

tion of Gelignite-Blas

aterials-Wood Pulp-P

us used, and Properties

osition and

of the skeletons of various species of diatoms. This earth occurs in beds chiefly in Hanover, Sweden, and Scotland. The best quality for the purpose of manufacturing dynamite is that which contains the largest quantity of the long tubular bacillari?, and less of the round and lanc

ed by the late Colonel

f Explosives"

inert base, acting me

xplosive base. No. 2 may be again divided in

Cha

other nitrate, o

ther nitro compound

the second is represented by the well-known Atlas powder; and the last includes the well-known an

ore practical and safe for use. The altered condition of the nitro-glycerine is effected by causing it to be absorbed in porous unexplosive substances, such as charcoal, silica, paper, or similar materials, whereby it is converted into a powder,

30 per cent. of water and organic matter. The water may be very easily estimated by drying a weighed quantity in a platinum crucible at 100° C. for some time and re-weighing, and the organic matte

should be as free as possible from grit of all kinds, quartz particles, &c., and should have a smooth feeling when rubbed between the finger and thumb, and should show a large quantity of diatoms when

temperature should be sufficiently high to make the guhr red hot, or the organic matter will not be burnt off. The time occupied in calcining will depend of course upon the quality of the guhr being operated upon. Those

between iron rollers fixed at the bottom of a cone or hopper, and revolving at a moderate speed

ine used should be quite free from water, and clear, and should have been standing for a day or two in the precipitating house. The guhr and nitro-glycerine are mixed in lead tanks (about 1-1/2 foot deep, and 2 to 3 feet long), in the proportions of 75 of the nitro-glycerine to 25 of the guhr, unless the guhr is found to be too absorbent, which will cause the dynamite to

nitro- glycerine poured on to it. The nitro-glycerine may be weighed out in indiarubber buckets. The whole is then mixed by hand, and well ru

and the descending piston forces the dynamite down the cylinder and out of the open end, where the compressed dynamite can be broken off at convenient lengths. The whole machine should be made of gun-metal, and should be upright against the wall of the building. The two girls, who sit at tables placed on each side of the press, wrap the cartridges in parchment paper. From these huts the cartridges are collected by boys every ten minutes or a quarter of an hour, and taken to the packing room, where they are packed in 5-lb. cardboard boxes, which are then further packed in deal boxes lined with indiarubber, and fastened down air ti

e chapter on "Analysis," and author's art

plosive qualities to such an extent that it can be made non-explosive except to a very strong fulminate detonator. The direct contact of water disintegrates dynamite, separating the nitro-glycerine, hence great caution is necessary in using it in wet places. It freezes at about 40° Fahr. (4° C.), and remains frozen at temperatures considerably exceeding that point. When frozen, it is comparatively useless as an expl

tion of the nitro-glycerine, which is much more sensitive to shock, and if accidentally struck with an iron tool, may explode. It is a dangerous thing to c

rays of the sun. It should, however, not be kept in a damp or moist place, as this is liable to cause exudation. Sunlight, if direct, can cause a

to undergo change, however, it rapidly becomes acid, and sometimes explodes spontaneously, especially if contained in resisting envelopes. Nevertheless, neutral and well-made dynamite has been kept for years in

or (this is similar to wet gun-cotton). It is, however, rendered much less sensitive to shock. With regard to the power of No. 1 dynamite, experiments made in lead cylinders give the relative value of No. 1 dynamite, 1.0; blasting gelatine, 1.4; and nitro

elot, "Explosives

about 7/8 diameter, laid end to end, and measuring one mile in length, would be exploded in one-quarter of a second by detonating a cartridge at either end.[A] Mr C. Napier Hake, F.I.C., the Inspector of Explosives f

mplete c

mical changes induced i

king and heating of the mat

h the blast-hole and the fis

The proportion of useful work obtainable has been variously estimat

Notes on Explosives," Jou

ne, and the absorbent is carbon in the form of burnt cork. It is as cheap as ordinary dynamite, and has greater explosive force, seeing that 90 per cent. of the

on of nitro-glycerine, wood-pulp, nitrate of soda, and carbonate of magnesia. This was the explosive used in the outrages

d of 70 parts of a solution of 2 to 3 per cent. of naphthalene in nitro-glyc

, are not manufactured. Among the best known after the ordinary No. 1 dynamite are forcite, ammonia dynamite, litho-fracteur, rendock, Atlas powder, giant powder, and the various explosive gelatines. They all co

of nitro- cellulose known as collodion-cotton, i.e., a mixture of the penta- and tetra-nitrates dissolved in nitro-glycerine, and made up with various proportions of wood-pulp, and some nitrate,

like substance, of a specific gravity of 1.5 to 1.55, slightly elastic, resembling indiarubber, and generally consists of 92 per cent. to 93 per cent. of nitro-glycerine, and 7 to

tton 99.11

tton 0

ted cotto

gen 1

ash

)_{6}, is not soluble in the above liquids, although it is soluble in acetone or acetic ether. It is very essential, therefore, that the nitro-cotton used in the manufacture of the gelatine explosives should be as free a

stand this test, it cannot be expected that the gelatine made from them will do so. It often occurs, however, that although both th

rcentage of nitrogen in the nitrated cotton should be over 11 per cent. It should be as free as possible from sand or grit, and should give but little ash upon ignition, not more than 0.25 per cent. The cotton, which is generally packed wet in zinc-lined wooden boxes, will require to be dried, as it is very essential indeed that none of the mat

s in weight. This will be a guide to the time that the cotton will probably require to be in the drying house. Samples generally contain from 20 to 30 per cent. of water. After drying for a period of forty-eight hours, a sample should be again dried in the oven at 100° C., and the moisture determined, and so on at intervals until the bulk of the cotton is fou

f a fan or Root's blower, the air being passed over hot bricks, or hot-water pipes before entering the building. The cotton should also be occasionally turned over by hand in order that a fresh surface may be continually exposed to the action of the hot air. The building itself may be heated by means of hot-water pipes, but on no account should any of the pipes be exposed. They should all be most carefully covered over with wood-work, because

trays. The one nearest to the hot air inlet should be selected. If the temperature of the house is kept at about 40° C. it will be quite high enough. The building must of course be properly ventilated, and it will be found very useful

gs. The various gelatine compounds, gelignite, gelatine dynamite, and blasting gelatine, are manufactured in exactly the same way. The forms known as gelatine dynamite diffe

ine B

Dynamite.

60.514 71.128

lose 4.888

7.178 4.

trate 27.420

.. 0.26

ugh the blasting gelatine is weight for weight more powerful, it is more difficult to make than either of the other two compounds, it be

n it. The whole is then well stirred up, and kept at a temperature of from 40° to 45° C. It should not be allowed to go much above 40° C.; but higher temperatures may be used if the nitro-cotton is very obstinate,[A] and will not dissolve. Great caution must, however, be observed in this case. The mixture

lly due to the nitr

-WERNER, PFLEIDERER, &

Beyond this the jelly should never be allowed to

e to communicate, so that the hot water can flow from one to the other consecutively. The temperature of the water should be about 60° C. if it is intended to gelatinise at 45° C., and about 80° if at 50° C.; but this point must, of

-MR M'ROBERTS' MIXER FO

r 6 feet high, outside the building, which is automatically supplied with water, and into which steam is turned. A thermomet

ure should be transferred to the mixing machine. The mixing machines are specially designed for this wo

ner, Pfleiderer, & Perkins, Ltd., after many years' experience in the mixing of explosive materials, and is now almost exclusively adopted in both Govern

Jour. Soc. Chem.

oper proportions of wood-pulp[A] and potassium nitrate should be added, and the whole well

from which the knots are removed. The pieces of wood are afterwards put through a machine which breaks them up into small pieces about an inch long, which are then crushed between rollers. These fragments are finally boiled with a solution of sodium bisulphite, under a pressure

h. Lime. Pi

45.47 53.09 56.9

0.41 3.93

t 2.65 2.47 3.

12.57 10.10

39.14 29.32

o thirty revolutions per minute. The bearings should be kept constantly greased and examined, and the explosive mixture carefully excluded. When the gelatine mixture has been thoroughly incorporated

.-PLAN OF THE BOX CONT

RTS' M

thyl-alcohol. (They are all too expensive, with the exception of acetone and methyl-alcohol, for use upon the large scale.) These liquids not only dissolve the nitro-cellulose in the cold, but render the resulting gelatine compoun

mite with amyl alcohol for this purpose. Di-n

ust be made of gun-metal or brass, and it consists of a conical case containing a shaft and screw. The revolutions of the shaft cause the thread of the screw to push forward the gelatine introduced by the

, Jour. Soc. Chem. Ind.,

33.-CARTRIDGE-MAKING

OSIV

a kind of brass frame, into which the gelatine issuing from the nozzle of the cartridge machine is forced, finding its way along a series of grooves. When the frame is full, a wo

screw shaft must be fixed outside the cone containing the gelatine. One of these machines can convert f

iarubber, and screwed down air tight, brass screws or zinc or brass nails being used for the purpose. These boxes are sent to the magazines. Before the boxes are fastened down a cartridge or so should be removed and tested by the heat test,

of the gelatine dynamite is cut from the cartridge of a length equal to its diameter. The edges must be sharp. This cylinder is to be placed on end on a flat surface (such as paper), and secured by a pin through the centre, and exposed for 144 cons

udation of nitro-glycerine. All the materials used in the manufacture of gelatine explosives should be subjected to analytical examinati

y for total combustion, either because an incomplete combustion gives rise to a greater volume of gas, or because the rapidity of decomposition and the law of expansion varies according to the relative proportions and the conditions of application. The various additions to blasting gelatine generally have the effect

ncrease the rapidity of explos

mportant that there should be no excess of nitro-glycerine, as this may diminish instead of augment the strength, owing to a difference in the mode of the propagation of the explosive wave in the liquid, and in the mixture. Nitro-glycerine at its freezing point has a tendency to separa

C.) without decomposition. At higher temperatures the nitro-glycerine will partially evaporate. When slowly heated, it explodes at 204° C. If, however, it contains as much as 10 per cent. of camphor, it burns without exploding.

elot, "Explosives

atine itself, its equivalent weight being 12,360 grms. The heat liberated by its explosion is equal to 19,381 calories, or for 1 kilo. 1,535 calories. Volume of gas

A: Roux an