122 SPECIFIC HEAT OF ATOMS. 



M. Dumas is disposed to modify the atomic theory so far 

 as to allow the divisibility of the atoms or ultimate masses 

 in which a body enters into combination, and to suppose that 

 they are groups of more minute atoms, into which they may 

 be divided by physical, but not by chemical forces. He dis- 

 tinguishes the atoms which correspond with equivalents as 

 chemical atoms, and allowing them to represent truly and 

 constantly the least quantities in which bodies combine, 

 still supposes that under the influence of heat and per- 

 haps other physical agencies, these molecules may be sub- 

 divided into atoms of an inferior order, of which for example, 

 two, four or a thousand are included in a single chemical 

 atom."* But surely such a view is entirely subversive of the 

 atomic theory. It is principally founded on the assumed 

 existence of a similarity between atoms in their capacity for 

 heat, and in their volume while in the gaseous state, in which 

 it would be more natural to admit a difference among different 

 atoms. 



SPECIFIC HEAT OF ATOMS. 



The quantity of heat necessary to raise the temperature of 

 equal weights of different bodies a single degree, varies accord- 

 ing to their nature, and may be expressed by numbers which 

 are the capacities for heat or specific heats of these bodies 

 (page 22). This difference appears in the numbers for several 

 simple bodies placed together in the first column of the table 

 below, among which no relation can be perceived. But if the 

 comparison is made between the capacity for heat not of equal 

 weights, but of atomic weights or equivalent quantities of the 

 same bodies, as in the second and third columns of the table, 

 then the numbers for several bodies are found to be nearly 

 the same, and those of others to bear a simple relation to each 

 other. 



* Lemons sur la Philosophic Chimique, professes au College de France, par 

 M. Dumas, page 233. Paris, 1837. 



