108 OF THE GENERATION AND [ SECT . ,. 



differently stated : it combines with eight times its weight of oxygen ; and 

 according to the experiments of 



Dr. Crawford . 67200 



Lavoisier . 41440 



Dalton - - . 44800 



3)153440 



Mean 51146 Ibs. of water is 

 raised 1 by one pound of hydrogen. 



The number 50,000 therefore represents the mean effect of hydrogen very 

 nearly, and, as far as we have compared it with other experience, seems to be 

 about the true effect. 



186. By the experiments of 



Lavoisier, 1 Ib. of phosphorus combining with oxygen 



raises 15400 Ibs. of water 1. 



Dalton - 8400 



2)23800 

 Mean 1 1900 



Sulphur combining with oxygen, according to Dalton, heats 2800 times its weight 

 of water one degree. 



187. From these we may proceed to compare the several compound bodies 

 on which experiments have been made, and also to show the proportions of 

 oxygen they consume. The first column of the following table contains the name 

 of the substance, and the author of the analysis ; the second column, its compo- 

 sition in decimal parts of its weight ; the third shows the quantity of oxygen each 

 of its components requires, and their sum, or that required for the substance ; the 

 fourth column shows the heat each component affords, and their sum is the whole 

 the substance yields ; the fifth and last column contains the whole heat afforded 

 by the substance according to experiment. 



