Feb. 13, 1890] 



NA TURE 



;53 



explosion at gun-cotton stores at Simmering, near Vienna, in 

 1862. 



It was at about this time that the attention of the English 

 Government, and through them of the lecturer, was directed to 

 the subject of gun-cotton, the Austrian Government having com- 

 municated details regarding improvements in its manufacture 

 accomplished by von Lenk, and results obtained in the extended 

 experiments which had been carried out on its application to the 

 various purposes above indicated, according to the system devised 

 by that officer. One of the results of the lecturer's researches, 

 subsequently carried on at Woolwich and Waltham Abbey, was 

 his elaboration of the system of manufacture and employment of 

 gun-cotton which has been in extensive? use at the Government 

 works with little if any modification for over eighteen years, and 

 has been copied from us by P'rance, Germany, and other countries. 

 By reducing the partially purified gun-cotton fibre to pulp, as in 

 the ordinary process of making paper, then completing its purifi- 

 cation when in that condition, and afterwards converting the 

 finely-divided explosive into highly compressed homogeneous 

 masses of any desired form and size, very important improve- 

 ments were effected in its stability, its uniformity of composition 

 and action, and its adaptability to practical uses, a great advance 

 being made in the exercise of control over the rapidity of com- 

 bustion or explosion of the material. 



No success had attended the experiments instituted in England 

 with wound cannon cartridges of gun-cotton threads made accord- 

 ing to von Lenk's plan ; on the other hand, a number of results 

 which at first sight appeared very promising were obtained at 

 Woolwich in 1867-68 with bronze field-guns and cartridges built 

 up of compressed gun-cotton masses arranged in different ways 

 (with varied air-spaces, &c.) with the object of regulating the 

 rapidity of explosion of the charge. But although the attainment 

 of high velocities with comparatively small charges of the material, 

 unaccompanied by any indications of injury to the gun, was 

 frequent, it became evident that the fulfilment of the conditions 

 essential to safety to the arm were exceedingly difficult to attain 

 with certainty, and appeared indeed to be altogether beyond 

 absolute control, even in so small a gun as the twelve-pounder. 

 Military authorities not being, in those days, alive to the advan- 

 tages which might accrue from the employment of an entirely 

 sfnokeless explosive in artillery, the lecturer received no en- 

 couragement to persevere with experiments in this direction, and 

 the same was the case with respect to the possible use of a 

 smokeless explosive in military small arms, with which, however, 

 far more promising results had at that time been obtained at 

 Woolwich. 



Abel's system of preparing gun-cotton was no sooner ela- 

 borated than its application to the production of smokeless 

 cartridges for sporting purposes was achieved with considerable 

 success by Messrs. Prentice, of Stowmarket. The first gun- 

 cotton cartridge, which found considerable favour with sports- 

 men, consisted of a roll of felt-like paper composed of gun-cotton 

 and ordinary cotton, and produced from a mixture of the pulped 

 materials. Afterwards a cylindrical pellet of slightly compressed 

 gun-cotton pulp was used, the rapidity of explosion of which 

 was retarded, while it was at the same time protected from 

 absorption of moisture, by impregnation with a small proportion 

 of india-rubber. Neither of these cartridges afforded promise of 

 sufficient uniformity of action to fulfil military requirements, but 

 after a series of experiments which the lecturer made with com- 

 pressed gun-cotton arranged in various ways, very promising 

 results were attained, especially with the Martini-Henry rifle 

 and a charge of pellet-form, the rapidity of explosion of which 

 was regulated by simple means. 



A sporting powder which was nearly smokeless had, in the j 

 meantime, been produced by Colonel Schultze, of the Prussian 

 Artillery, from wood cut up into very small cube-like fragments, 

 converted into a mild form of nitro-cellulose after a preliminary | 

 purifying treatment, and impregnated with a small portion of an 

 oxidizing agent. Subsequently the manufacture of the Schultze 

 powder was considerably modified ; it was converted into the 

 granular form, and rendered considerably niore uniform in 

 character and less hygroscopic, and it then bore considerable 

 resemblance to the E.G. powder, a granulated nitro-cotton 

 powder, produced, in the first instance, at Stowmarket, and 

 consisting of a less highly nitrated cotton than gun-cotton 

 (trmitrocellulose), incorporated in the pulped condition with a 

 somewhat considerable proportion of the nitrates of potassium 

 and barium, and converted into grains through the agency of a 

 solvent and a binding material. Both of these powders pro- 



duced some smoke when fired, though the amount was small in 



I comparison with that from black powder. They did not compete 



I with the latter in regard to accuracy of shooting, when used in 



I arms of precision, but they are interesting as being the fore- 



, runners of a variely of so-called smokeless powders, of which 



gun-cotton or nitro-cotton is the basis, and of which those of 



Johnson and Borland, and of the Smokeless Powder Company, 



are the most prominent in this country. 



In past years, both camphor and liquid solvents, such as 



acetic ether and acetone for gun-cotton, and mixtures of ether 



I and alcohol for nitro-cotton, have been applied to the hardening 



of the surfaces of compressed masses or granules of those 



j materials, by von Forster and others, with a view to render 



j them non-porous, and in the E.G. powder manufacture the 



j latter solvent was thus applied to harden the powder-granules. 



j In the Johnson- Borland powder camphor is applied to the same 



purpose ; in smokeless powders of French and German manu- 



I facture acetic ether and acetone have been used, and the solvent 



I has been applied not merely to harden the granules or tablets 



, of the explosive, but also to convert the latter into a homogeneous 



horn-like material. 

 1 Much mystery has surrounded the nature and origin of the first 

 smokeless powder adopted, apparently with undue haste, by the 

 1 French Government, for use with the Lebel magazine rifle. A 

 I few particles of the Vieille powder, or Poudre B, were seen by 

 the lecturer about two years ago, and very small specimens- 

 appear to have fallen into the hands of the German Government 

 about that time. They were in the form of small yellowish- 

 brown tablets of about 0*07 inch to 01 inch square, of the 

 thickness of stout notepaper, and had evidently been produced 

 by cutting up thin sheets of the material. They appeared to 

 contain, as an important ingredient, picric acid (the basis 

 of "melinite") a substance extensively used as a dye, and ob- 

 tained by the action of nitric acid, at a low temperature, upon 

 carbolic acid and cresylic acid, constituents of coal tar. Origin- 

 ally produced by the action of nitric acid upon indigo, and 

 afterwards by similar treatment of Botany Bay gum, it was first 

 known as carbazotic acid, and is one of the earliest of known 

 explosives of organic origin. When sufficiently heated, or when 

 set light to, it burns with a yellow smoky flame, and even very 

 large quantities of it have been known to burn away somewhat 

 fiercely, but without exploding. Under certain conditions, 

 however, and especially if subjected to the action of a powerful 

 detonator, it explodes with very great violence and highly 

 destructive effects, as pointed out by Sprengel in 1873, and 

 recent experiments at Woolwich have shown that it does this 

 even, as in the case of gun-cotton, when it contains as much as 

 15 per cent, of water. It is no longer a secret that picric acid 

 at any rate forms the basis of the much vaunted and mysterious 

 explosive for shells for which the French Government were said 

 to have paid a very large sum of money, and the destructive 

 effects of which have been described as nothing less than mar- 

 vellous. M. Turpin patented, in 1875, the use of picric acid- 

 alone as an explosive for shells and for other engines of destruc- 

 tion, and whether or not his claims to be the inventor of melinite 

 are valid, there appears no doubt that his patent in France was 

 the starting-point of the development and adoption of that 

 explosive. 



The attention thus directed in France to the properties of 

 picric acid appears to have given rise to experiments resulting in 

 its employment as an ingredient of the first smokeless powder 

 {Poudre B) adopted for the French magazine rifle. 



The idea of employing picric acid preparations as explosive 

 agents for propulsive purposes originated with Designolle about 

 twenty years ago, but no useful results attended the experiments 

 with the particular mixtures proposed by him. It is certain that 

 the recent adaptation of that substance in France was of a 

 different character, and that, promising as were the results of the 

 new smokeless powder, of which it formed an ingredient, and of 

 which a counterpart was made the subject of experiments at 

 Woolwich about three years ago, its deficiency in the all- 

 essential quality of stability must have been at any rate one 

 cause of its abandonment in favour of another form of smokeless 

 powder, which there is reason to believe is of more simple 

 character. 



In Germany, the subject of smokeless powder for small arms 

 and artillery was being steadily pursued in secret, while the 

 sensational reports concerning Poudre B were spread about in 

 France, and a small-arm powder, giving excellent results in 

 regard to ballistic properties and uniformity, was elaborated at 



