THE TECHNOLOGIST. [Sept. 1, 1864. 



52 ON THE MECHANICAL NATURE AND 



in a proper box made for the purpose, and simply laid down near the 

 gate, and not even nailed to it, this 25 lbs. would shiver the gate into 

 splinters. The bag which suits the powder happens not to suit the 

 gun-cotton. 



Gun-eotton is, therefore, a power of a totally different nature from 

 gunpowder, and requires complete study to know its nature and under- 

 stand its use. It appears that both gunpowder and gun-cotton have 

 special qualities, and may be peculiarly suited for peculiar uses. It 

 is the duty of a wise people to make use of both to the ends they each suit 

 best, without prejudice arising from the accident of novelty or antiquity. 

 The nature of gun-cotton requires a double study, chemical and 

 mechanical. It is not like steam, the same substance, whether in the 

 form of ice, or water, or steam. It is one substance when as gun-cotton 

 it enters the gun, and quite a different one when it explodes and leaves 

 the gun. Not only are the solids which enter converted into gas, but 

 they form totally new combinations and substances. So that the mar- 

 vellous changes which the chemist effects by the magic of his art take 

 place in an instant of time, and during that almost inconceivably 

 minute period of time, in a laboratory intensely heated, old substances 

 are dissolved, their material atoms are redistributed, each atom released 

 selects by affinity a new partner, these new unions are cemented, and at 

 the end of this prolific instant totally new combinations of matter, 

 forming what we call new substances, issue from the gun. It so happens 

 that of these new substances, formed out of gun-cotton, all are pure 

 transparent gases, while in the case of gunpowder there remain 68 per 

 cent, of solid residue, and only 32 per cent, are pure gases. 



The mechanical application of gun-cotton may be considered to be 

 due exclusively to Major-General Lenk, of the Austrian service. Pure 

 gun-cotton becomes either a powerful explosive agent, or a° docile per- 

 former of mechanical duty, not according to any change in its compo- 

 sition, or variations in its elements or their proportions, but according 

 to the mechanical structure which is given to it, or the mechanical 

 arrangements of which it is made a part. It was General Lenk who 

 discovered that structure was quabty, and mechanical arrangement 

 the measure of power, in gun-cotton ; and in his hands, a given quan- 

 tity of the same cotton becomes a mild, harmless, ineffectual firework, 

 a terrible, irresistible, explosive agent, or a pliable, powerful, obedient 

 workman. 



The first form which General Lenk bestowed on gun-cotton was 

 that of a continuous yarn or spun thread. Gunpowder is carefully 

 made into round grains of a specific size. Gun-cotton is simply a long 

 thread of cotton fibre, systematically spun into a yarn of given weight 

 per yard, of given tension, of given specific weight. A hank of a given 

 weight is reeled, just like a hank of cotton yarn. to be made into cloth, 

 and in this state gun-cotton yarn is bought and sold like any other 

 article of commerce. 



