378 Dr, Ure’s new experimental researches 
Whatever reception these speculations may experience* 
they must not be confounded with the experiments n the 
expansions of metallic rods, and the corollaries, which have 
a distinct and independent existence. 
§ II. On the doctrines of capacity, as connected with the pre- 
ceding investigation. 
Dr. Crawford and De Luc, tried to verify the justness of 
the thermometric indications, by mixing together water at 
si 2 0 and 32 0 ; when the former found 122 0 , and the latter 
119 0 , to be the resulting temperature. De Luc’s number is 
3 0 below the mean ; Dr. Crawford’s is exact. This inge- 
nious philosopher afterwards sought to confirm the evidence 
thus given to the accuracy of the scale, by other experiments, 
which were however of rather an equivocal import. Both of 
the above results have been condemned and rejected by Mr. 
Dalton: he states the true mean temperature to be not 
122 0 , nor even 119 0 , but 110°. For this deviation, the reasons 
which he assigns appear, independently of all arguments 
derived from other quarters, to be in themselves inconclusive. 
He says,“ the temperature of the above mixture ought to be 
found above the mean 122 0 .” “ Water of these two tempe- 
“ ratures (32 0 and 212 0 ) being mixed, loses about of its 
“ bulk. This condensation of its volume * must expel a 
“ quantity of heat, and raise the temperature above the 
“ mean." p. 7. Again, p. 50, “ that water increases in its 
“ capacity for heat with the increase of temperature, I con- 
“ sider demonstrable from the following arguments. 1st. A 
* That condensation of volume in a liquid, is no proof of the expulsion of heat, is 
shown in my Essay on Sulphuric Acid. 
