164 ACID1FIABLE COMBUSTIBLES. 



1 atom boracic acid 3 or 57' 143 



2 atoms water 2-25 42-85? 



5-25 100 



which almost coincides with Davy's experiment. 

 6. Very few of the borates have hitherto been 

 Se of ami analyzed, and very few of them accurately. 

 However, from Berzelius' analysis of borate of 

 ammonia, I think we are entitled to conclude 

 that the salt is composed of 



1 atom boracic acid 3 



1 atom ammonia . 2-125 



2 atoms water . . 2-25 



7-375 

 Berzelius obtained 



Boracic acid 2-659 

 Ammonia 2-125 



Water 2-25 



7-034 



Analysis of j t It was not till I had satisfied myself of the 

 true atomic weight of boracic acid from the 

 specific gravity and combinations of fluoboric 

 acid, that I became acquainted with M. Arfwed- 

 son's method of analyzing the borates by means 

 of fluor spar. He mixes the borate to be 

 analyzed with a determinate quantity of fluor 

 spar reduced to the state of a very fine powder, 

 and exposes the mixture with the requisite 



