THE ALUMNI JOURNAL. 



311 



Section (Prof. Roscoe), to Widnes to 

 visit the works of Messrs. Gaskell, Dea- 

 con & Co., will well remember that at 

 these works they saw, side by side, 

 Weldon's process and Deacon's process 

 in operation, and no one present will 

 have forgotten the thoughttul, flashing 

 eyes and impressive face of Mr. Deaeon 

 when he explained to his visitors the 

 theoretical views he had formed as re- 

 gards his process. 



Mr. Deacon had made a careful study 

 of thermo-chemistry, which had been 

 greatly developed during the predeeding 

 decade by the painstaking, accurate and 

 comprehensive experiments of Julius 

 Thomsen and Berthelot, and had led the 

 latter to generalizations, which, although 

 not tully accepted by scientific men, have 

 been of immense service to manufacturing 

 chemistry, 



Mr. Deacon came to the conclusion 

 that if a mixture of hydrochloric acid 

 with atmospheric air was heated in the 

 presence of a suitable substance capable 

 of initiating the interaction of these two 

 gases by its affinity to both, it would to 

 a very great extent be converted into 

 chlorine with the simultaneous formation 

 of steam, because the formation of steam 

 from oxygen and hydrogen gives rise to 

 the evolution of a considerably larger 

 quantity of heat than the combination of 

 hydrogen and chlorine. Mr. Deacon 

 found that the salts of copper were a very 

 suitable substance for this purpose and 

 took out a patent for this process in 1868 . 

 He entrusted the study of theoretical and 

 practical problems connected with this 

 process to Dr. Ferdinand Hurter who 

 carried them out in a manner which will 

 always remain memorable and will 

 never be surpassed, as an example of 

 the application of scientific methods to 

 manufacturing problems and which soon 

 placed this beautiful and simple process 



on a sound basis as a manufacturing 

 operation. 



In the ordinary course of manufacture, 

 the major part — about two- thirds — of the 

 hydrochloric acid is obtained mixed with 

 air and a certain amount of steam, but 

 otherwise very little contaminated. In- 

 stead of condensing the muriatic acid 

 from this mixture of gases by bringing it 

 into contact with water, Mr. Deacon 

 passed it through a long series of cooling 

 pipes to condense the steam which of 

 course absorbed hydrochloric acid and 

 formed a certain quantity of strong muri- 

 atic acid. The mixture of gases was 

 then passed through an iron superheater 

 to raise it to the required temperature 

 and thence through a mass of broken 

 bricks impregnated with sulphate or 

 chloride of copper contained in a chamber 

 or cylinder called a decomposer, which 

 was protected from loss of heat by being 

 placed in a brick furnace kept sufficiently 

 hot. In this apparatus from 50 to 60 per 

 cent, of the hydrochloric acid in the 

 mixture of gases was burnt to steam and 

 chlorine. In order to separate this 

 chlorine from the steam and the remain- 

 ing hydrochloric acid the gases were 

 washed with water and subsequently with 

 sulphuric acid. The mixture now con- 

 sisted of nitrogen and oxygen, containing 

 about 10 per cent, of chlorine gas, which 

 could be utilized without any difficulty 

 in the manufacture of bleach liquors and 

 chlorate of potash, and which Mr. Dea- 

 con also succeeded in using for the manu- 

 facture of bleaching powder, by bringing 

 it into contact in specially constructed 

 chambers with large surfaces of hydrate 

 of lime. Within recent years this latter 

 object has been attained in a more ex- 

 peditious and perfect manner by con- 

 tinous mechanical apparatus (of which 

 those constructed by Mr. Robert Hasen- 

 clever and Dr. Carl Danger, have been the 

 most successful), in which the hydrate of 



