SECT. III.] 



CONDENSATION OF STEAM. 



Ill 



188. These are the results as far as the latest researches in chemistry enable 

 us to carry the comparison : it is sufficient to show that the correspondence is very 

 close, and that the numbers we have selected for the binary compounds are very 

 nearly the true ones. It will be particularly remarked, that in wax, oil, and those 

 substances which are likely to afford the most accurate results, theory and 

 experiment agree. 



There is, however, still another mode of prosecuting our inquiries, and perhaps 

 with equally satisfactory results. 



189. In gas works, from the quantity of gas and coke afforded by a given 

 quantity of coal or other matter, we have an approximate means of measuring 

 its effect as fuel ; but from the want of a correct knowledge of the density of 

 the gas, in each case, we are obliged to assume it to be the same as carbureted 

 hydrogen. 



1 The experiments marked Da. were made by Dalton, Ru. Rumford, and Cr. Crawford. The 

 analyses of the substances are referred to their authors ; Dr. Ure's will be found in his ' Chemical 

 Dictionary,' and Dr. Thomson's in his 'Annals of Philosophy.' 



z This is the result collected from a comparison of Lavoisier's experiments. Treatise on Warm- 

 ing Buildings, art. 31. 



