Alfred Nobel

“ In the firing of explosives made according to the present invention, the gases produced at first are of a comparatively low temperature, as the substances apt to lessen the velocity of combustion, also tend to lower the temperature of the gases produced. This is of great consequence in respect of protecting the bore of the gun from erosion, for, with the high pressure during the first moments of combustion, any increase in temperature greatly increases the danger of erosion. ”

“ So great is the absorbent capacity of this earth, that it will take up about three time its own weight of nitro-glycerine and still retain its powder-form, thus leaving the nitro-glycerine so compact and concentrated as to have very nearly its original explosive power ”

“ Nitro-glycerine, as well as the analogous explosives hereinbefore named, being liquid, is in such condition that it cannot escape from the influence of the initial explosion, (as, for instance, when placed in a bore-hole for blasting,) receives and propagates the initial pressure through its whole mass, and the first impulse of explosion is communicated throughout the whole charge, effecting its instantaneous decomposition and explosion. By the terms impulse of explosion is meant motion produced to effect the explosion by suddenly-communicated force. ”

“ Nitro-glycerine, for example, if ignited in an open space, is slowly decomposed and takes fire, but the flame is apt to die out when the match is withdrawn; hence it cannot, under ordinary circurmstances, be looked upon as a ready explosive agent; for while gunpowder, and other substances used as explosives prior to Nobel's invention, al­ways explode or deflagrate throughout the whole mass when fire is set to them, nitro­glycerine and the analogous substances before named will not explode from the mere contact of flame. ”

“ Nobel's invention consisted in the discovery that nitro-glycerine could be made rapidly and in large quantities by the methods hereinafter described—the object being to secure a rapid and continuous mixing of streams of mixed acids and glycerine without creating sufficient reaction to produce oxidation. ”

“ In blasting, the powder is pressed tightly about the cap and fuse, and tamping, of sand or other proper material, added, and pressed but not pounded in. A tamping firmly pressed is as good as if rammed in the most solid manner.
The fuse explodes the cap, and this explosion explodes the powder.
I will add here that by carefully packing the end of a good fuse amidst the powder of a charge enclosed, like a blasting charge, in a tight place, the fuse alone will explode the powder, especially if the powder is strongly charged with nitro-glycerine. ”

“ Charges for rifles may be produced in the form of tubes, in the same way as is usual for ballistite and similar kinds of explosive, only with the difference that the nozzle of the apparatus used in producing the tubes, is arranged for simultaneously squeezing out several concentric layers of different compositions, which, owing to their plasticity, will appear as only one coherent mass. ”

“ A fourth mode of producing the initial explosion is by means of a spark, or by heat developed by a powerful current of electricity within the charge of nitro-glycerine, which is so inclosed as not to afford an escape to the gas developed thereby. ”

“ When nitric acid of a high specific gravity is used for the preparation of nitro-glycerine, the temperature is much increased by the reaction. It is, therefore, better to introduce the nitric acid and the glycerine gradually into the sulphuric acid, allowing the mixture to cool between each operation.
In the other method, the mixture of sulphuric and nitric acids is placed in one vessel and the glycerine in another; from each of these vessels a pipe conducts the streams of acids and glycerine into the mixing-tube. ”

“ Instead of the nitrate of soda, either of the nitrates of potash, baryta, or lead may be employed, and, instead of resin, other carbons and hydrocarbons, as coal, sugar, starch, wood, charcoal, &c., may be used. If coal is employed, such as contains the greatest proportion of hydrogen answers the best for this purpose.
It should be observed that the amount of nitro-glycerine which can be retained by the other ingredients will depend upon the degree of fineness to which they are pulverized, and will vary with the ingredients used, and also with the temperature of the atmosphere ”

“ The nature of the invention consists in forming out of two ingredients long known, viz, the explosive substance nitro-glycerine, and an inexplosive porous substance, hereafter specified, a composition which, without losing the great explosive power of nitro-glycerine, is very much altered as to its explosive and other properties, being far more safe and convenient for transportation, storage, and use, than nitro-glycerine. ”

“ The gas in passing through, will absorb and carry off a certain quantity of the liquid, and is by accurately measuring or weighing the quantity that remains in the vessel that the amount of gas that has passed through is ascertained. ”

“ The manufacture of explosive compounds as above described, consisting in placing upon each other, by pressing, rolling, or otherwise joining together, layers of a plastic explosive compound of different chemical composition, as respects rate of combustion, in the order and for the purpose above set forth. ”

“ Second, by the use of what Nobel calls "igniters" or "burners," being a small tube of gases, paper, or other material, filled or charged with gunpowder or other easy explosive, and furnished with a fuse or other means of igniting the same by fire or by an electric spark. The burner maybe introduced into the nitroglycerine, and, being fired in any convenient manner, its explosion gives to the nitro-glycerine the requisite impulse of explosion. These igniters may be greatly varied in construction ”

“ To effect the explosion of this compound a tube or cap containing fulminate of mercury or other suitable detonating substance, and affixed to the end of a fuse, is inserted in the charge of the above-described compound, the fuse being fired in the usual way, or, if preferred, the cap inserted in the compound may be fired by electricity without a fuse. ”

“ The effect of these combinations will produce an explosive especially suitable for certain blast­ing purposes—for example, in crevice rock—and greatly superior either to gunpowder or gun-cotton in explosive force, and quite readily exploded, so that it may be fired and exploded by means of a match or electric spark in like manner as gunpowder or gun-cotton alone. ”

“ A modification of this apparatus may be used to insure the thorough mixing of the acids and glycerine by the use, instead of the conical mixing-tube c, of a tube which is put into rapid motion by a wheel or other contrivance, into the upper end of which the acids and glycerine are separately introduced, which will combine, as they flow through it, so instantaneously that the product (nitro-glycerine) is formed as quickly as they can pass through the tube. ”

“ Attempts have been made to impart a progressive combustion to ordinary black powder, by using in the outer layers of the same, saltpetre crystals of larger size than in the inner layer, but in this way the desired result will not be obtained, owing to the fact that the larger crystals make the product more porous, and as the quickness of combustion of powder increases with the porosity of the same, it will easily happen that a result is obtained which is contrary to the one sought for. ”

“ In general terms, my invention consists inmixing with nitro-glycerine a substance which possesses a very great absorbent capacity, and which, at the same time, is free from any quality which decompose, destroy or injure the nitro-glycerine or its explosiveness. ”

“ An igniter for producing the explosion of nitro-glycerine, consisting of a case of wood or other suitable material for holding the ini­tial explosion-charge, closed with a cork or plug, and a fuse or other means of ignition substantially as hereinbefore described. ”

“ Such substances may be substituted the one for the other, as they all serve the same purpose, viz., to modify the rate of combustion of the explosive. For large guns, it is preferable to manufacture the charge by using several layers having various rates of combustion, which increase towards the centre of the charge. Thus, the innermost layer will consist of a composition of quick combustion, intermediate layers of slower combustion, and outer layers of very slow combustion. ”

“ The substance which most fully meets the requirements above mentioned, so far as I know or have been able to ascertain from numerous experiments, is a certain kind of silicious earth or silicic acid, found in various parts of the globe, and known under the several names of silicious marl, tripoli, rotten-stone, &c. ”

“ The explosive compound manufactured according to this invention differs essentially from the above mentioned powder, in that its progressive quality is obtained, in the latter case, in a purely mechanical way, by altering the size of the saltpetre crystals, while in the former case it is obtained in a chemical way, by introducing chemical substances in the outer layers of the compound, capable of modifying its explosive character. ”

“ The coils of these rolls are kept apart by means of longitudinal strips of the like material, the object of the insertion of these strips being to form conducting passages for the fire from the fuse to act upon the surfaces of the coils.--The rolls thus formed may be of any desired length, and, when a heavy charge is required, it will be convenient to fill the cartridges with short rolls of corresponding diameter, placed one upon the other. ”

“ Improvement in Exploding Nitro-Glycerine. Reissue No. 4,817 - Division C: Improvement in the Manufacture of Nitro-Glycerine. Reissue No. 4,818 - Division D: Improvement in Useful Compounds Containing Nitro-Glycerine. Reissue No. 4,819 - Division E: Improvement in Nitro-Glycerine Compounds. Oct 21, 1873, U.S. Patent No. 50,617: Improved Substitute for Gunpowder. Reissue No. 5,619 - Improvement in Explosive Compounds. Reissue No. 5,620 - Improvement in exploding Nitro-Glycerine. Reissue No. 5,621 - Improvement in Methods of Exploding Nitro-Glycerine. Mar 17, 1874, U.S. Patent No. ”