82 EXPERIMENTS OF THOMSON. 



the atoms of all simple bodies have the same specific 

 heat; because when they vary, it is in multiple 

 or submultiple ratios, or nearly so ; and that the 

 atomic equivalents of all bodies which do not ac- 

 cord with this assumed law, ought to be altered 

 and made to agree with it. (Ann. de Chim. et 

 de Phys. torn, x.) 



The recent efforts of Dr. Thomson to verify 

 the hypothesis of Dulong and Petit, have not 

 been more successful ; as will appear from the 

 following table, representing the atomic weight 

 of twenty-six simple substances, (compared with 

 oxygen as unity,) their specific heat, and the re- 

 sulting product. He observes, that " if the spe- 

 cific heat of bodies multiplied into their atomic 

 weights be a constant quantity, it will follow that 

 every simple atom is surrounded with the same 

 quantity of heat." (Records of Science, April, 

 1836.) 



Atomic weight. Specific heat. Product. 



Carbon 0.75 0-257 0-192 



Silicon 1- ,... 0-187 .... 0-187 



Aluminum 1-25 0-150 0-187 



Oxygen 1 0-236 0-236 



Chlorine 4-5 0'827 0-372 



Bromine 10 0-472 0-437 



Hydrogen 0-125 3-293 0-412 



Nitrogen 1-75 .... 0-269 0-472 



Sulphur 2 0-188 0-376 



Arsenic 4-75 0-081 .... 0-385 



Antimony 8 .... 0-047 9-376 



Tellurium 4 0-091 0.364 



Iron 3-5 .... 0-110 .... 0-385 



Nickel 3-625 0-103 . . 0-375 



