180 HENRY DEACON 



by the employment of salts of copper in 

 conjunction with sulphurous acid gas together 

 with oxygen or air. The process is to im- 

 pregnate pieces of burnt clay with a strong 

 solution of sulphate of copper and dry them ; 

 these are placed in a tower, and through them 

 are passed heated mixtures of sulphurous acid 

 gas and oxygen in equivalent proportions 

 with or without super-heated steam, and sul- 

 phuric acid is produced, and can be condensed 

 in any convenient manner. The success of 

 this invention depends not only upon the use 

 of such a chemical re-agent as sulphate of 

 copper, but also upon the temperature at 

 which it is performed, which temperatures 

 vary between the point at which sulphate of 

 copper begins to be decomposed in a current 

 of hot air, and about that point at which tin 

 melts, so that the sulphate of copper may 

 continue and remain sulphate of copper. 



No. 1,682. 2/th June, 1871. Improve- 

 ments in apparatus for producing chlorine and 

 sulphuric acid; this apparatus applies to the 

 process previously specified. 



No. 691. 1 5th March, 1871. The em- 

 ployment in the manufacture of bleaching- 

 powder, and of sulphate of soda, &c., of 

 inclined shelves on which are placed solid 



