448 



Anniversary Meeting. 



[Nov. 30, 



Phil. Trans, vol. clvi. p. 269, " On the Manufacture and Composition of 

 Gun-cotton." In this paper, as the result of a long series of experiments, 

 made with great accuracy, the conditions were laid down for its uniform 

 manufacture and purification ; and the true nature of gun-cotton (tri- 

 nitro-cellulose) was finally established by an exhaustive series of analytical 

 and synthetical experiments. 



This paper was followed by another in 1867, published in the Philo- 

 sophical Transactions, vol. clvii., entitled, " On the Stability of Gun- 

 cotton," which was considered worthy of being made the Bakerian Lecture 

 for that year. This memoir details the results of four years' extensive 

 experiments on the effects of light and heat on gun-cotton, and upon the 

 protective action of water at low and high temperatures. It will be 

 recollected that the uncertain stability which had been characteristic of 

 gun-cotton was conclusively traced to minute quantities of unstable sub- 

 stances remaining in the fibre, even after the most careful purification 

 by the methods hitherto known, and the efficiency of simple measures 

 for securing the stability of gun-cotton was established. This led ulti- 

 mately to the development of a system of manufacture of gun-cotton 

 which permitted of its ready manufacture in a high state of purity 

 (pulping). 



Mr. Abel did not, however, confine his attention to gun-cotton ; 

 and, indeed, in 1864 had sent in a paper to the Royal Society, which 

 was published in the ' Proceedings,' vol. xiii., on " Some Phenomena 

 exhibited by Gun-cotton and Gunpowder under special conditions," in 

 which the behaviour of these substances when exposed to high tempera- 

 tures in rarefied atmospheres and in different mechanical conditions was 

 described. 



In 1869 a memoir, entitled " Contributions to the History of Explosive 

 Agents," was printed in the Philosophical Transactions, vol. clix. In this 

 memoir is discussed the influence of more or less strong confinement and 

 other mechanical conditions under which the detonation of such com- 

 pounds and mixtures was developed. It will be recollected that some 

 striking results were obtained in the examination of the behaviour of ex- 

 plosive compounds when exposed to initiative detonations of different 

 character. 



These phenomena were more fully discussed in a second memoir, pub- 

 lished in the Philosophical Transactions for 1874, vol. clxiv. ; it includes an 

 exhaustive investigation of the transmission of detonation from one mass 

 of gun-cotton, fulminates, and nitro-glycerine to other distinct masses in 

 the open air, and also through the agency of tubes. The causes of inter- 

 ference with the transmission of detonation-force, and the development 

 of detonation as distinguished from explosion, were clearly discussed. 

 The influence of dilution by solids and by liquids on the susceptibility of 

 explosives to detonation, and also the velocity with which detonation is 

 transmitted by different explosive agents under various conditions, was 



