1808. ^T. 30.] PROFESSOR DAVY. 357 



plate thirty-two square inches ; so that the whole 

 number of double plates is 2,000, and the whole 

 surface 128,000 square inches. This battery was 

 charged with sixty parts water and one .part of nitric 

 acid. It gave a spark from charcoal points through 

 four inches of air.' 



On July 12 the Laboratory Notes say, ' Tried the ex- 

 periments upon the decomposition of the earths by iron 

 wire with the happiest results.' These were obtained 

 with the battery of only twenty pair. 



On July 18 he wrote, 'In pursuit of the researches on 

 the deoxygenation of diamond and charcoal. 



< Is not diamond the 2-oxide of carbon, charcoal 

 the 1 -oxide, the gaseous oxide of carbon a triple 

 compound of hydrogen, nitrogen, and charcoal ? ' 



On September 21, 22, 23, 24, 25, 26, 27 experiments 

 were tried on the production of cold by induced elec- 

 tricity. He tried the decomposition of sulphur ' with 

 success.' He tried to decompose mercury in the 

 Torricellian vacuum ' with success apparently. ' 



' Sulphur, after giving out hydrogen by electricity, 



had lost its yellow colour and was become brownish, 



but still non-conducting, crystalline, and transparent.' 



Numberless experiments were made on the action of 



potassium on ammonia and on nitrogen. 



In November he must have injured his right hand, 

 for his notes are made with his left hand on the 19th 

 and 20th of this month. 



On December 15 he gave another Bakerian lecture 

 on New Analytical Researches on Alkalies, Phosphorus, 

 Sulphur, &c. In this paper he says his chief object 



