OF MAGNESIA, 307 



Ii*o7o grains of this salt were kept in a red 

 heat till nothing remained but pure magnesia, 

 which weighed 2*5 grains. As the salt was 

 neutral, its constituents are obviously 



1 atom acetic acid 6-25 



1 atom magnesia 2-50 



5 atoms water 5-625 



14-375 



11. Oxalate of magnesia is a tasteless salt, 

 which can only be obtained in the state of a 

 white powder. To determine its composition I 

 took 9*25 grains of the salt in a state in which it 

 did not alter the colour of vegetable blues, and 

 exposed them to a strong red heat in a platinum 

 crucible ; there remained behind 2%5 grains of 

 pure magnesia. This being equivalent to an 

 atom of magnesia, it is obvious that the oxalic 

 acid in the salt amounted to 4%5, or an atom. 

 Hence, the constituents of oxalate of magnesia 

 are 



1 atom oxalic acid 4-5 



1 atom magnesia 2-5 



2 atoms water 2 -2 5 



9-25 



If the oxalate of magnesia be dried by means of 

 artificial heat, the water contained in it is always 

 less than two atoms. 



12. Binoxalate of magnesia. This salt may 



