58 



SIXTH REPORT 1836. 



By subtracting the 215"-5 (the time the empty flasks took to cool) 

 from the numbers in the preceding table, we obtained the ratios of the 

 specific heat of equal volumes of the above mixtures. By dividing 

 these numbers by the specific gravities of the various liquids as given 

 above, we obtain the specific heats of equal weights of each. The 

 following table shows these specific heats, that of water being reck- 

 oned unity. 



To know how far these numbers accord with the theory of Dr. Ir- 

 vine, at present universally admitted, namely, that the heat evolved 

 when oil of vitriol and water are mixed is owing to the diminution of 

 the specific heat, we must make a comparison of the specific heats 

 above found with the specific heat of the mixture, supposing it a mean 

 of the specific heats of the acid and water without any change. This 

 is done in the following table. 



The slightest comparison of the second and third columns of the 

 table is suflficient to show that the theory of Dr. Irvine cannot be ac- 

 curate. The specific heat of a compound of 1 atom oil of vitriol and 



