554 



Dr. C. K. Akin on Ray -Transmutation. 





HeatX 

 absorbed by 

 decompo- 

 sition. 



Heat evolved by combina- 

 tion. 



Raoult. 



Favre and 



Silbermann. 



Water 



-33803 

 -29895 





34462 

 29605 

 40192 

 34500 



Sulphate of copper 



Hydrochloric acid (dilute) ... 

 Cupric chloride 



-33859 

 -28371 



35200 

 29500 



Observations. 



Water. — The number —83803 is the mean of the results, 

 agreeing within -^ obtained with water containing sulphuric 

 acid or soda. 



Sulphate of Copper. — The sulphate of copper employed was 

 acidulated beforehand with y^th of sulphuric acid, in order that 

 its conductivity might not alter during the experiment. 



Hydrochloric Acid. — The acid employed was of such a strength 

 that it decomposed exactly into hydrogen and chlorine, but 

 nevertheless evolved no heat when mixed with water. The 

 concentrated acid gives a lower number ; but if the heat which 

 this acid evolves by combination with excess of water is added 

 to the result, it makes up very nearly the mean value 33859. 



Cupric Chloride. — As this compound is converted into sub- 

 chloride of copper in contact with the negative pole, it could 

 not be employed. The difficulty was got over by putting acidu- 

 lated sulphate of copper on the side of the negative electrode, 

 and hydrochloric acid saturated with chlorine on the side of the 

 positive electrode. According to the law of moduli, the quan- 

 tity of heat (28371) destroyed by this voltameter ought to be 

 that which corresponds to the decomposition of chloride of cop- 

 per, CuCl. 



LXVI. Note on Ray-Transmutation. By Dr. C. K. Akin.* 



IN a communication made by Prof. Tyndall to the (last) 

 November Number of the Philosophical Magazine, entitled 

 " On Luminous and Obscure Radiation," the following sentences 

 occur: — "Dr. Akin inferred from the paucity of luminous rays 

 evident to the eye, and a like paucity of extra-violet rays, as 

 proved by the experiments of Dr. Miller, that the radiation from 

 a flame of hydrogen must be mainly extra-red ; and he con- 

 cluded from this that the glowing of a platinum wire in a hy- 

 drogen-flame, as also the brightness of the JQruinrnond light in 



* Communicated by the Author. 



