BAXTER AND COFFIN. — ANALYSIS OF SILVER ARSENATE. 191 



gram respectively, the average being 0.00030 gram. This correction 

 was confirmed in another experiment in which the hard glass tube was 

 kept at the highest temperature obtainable with the blast lamp for one 

 hour. The observed gain in weight of the absorption tube was 0.00048 

 gram. A negative correction of 0.00030 gram was applied in each 

 water determination. 



In order to allow for moisture the weight of the arsenate was there- 

 fore always corrected by subtracting 0.000056 gram per gram of salt. 

 Ebaugh took no notice of the water contained in silver arsenate which 

 had been dried at only 170°. 



The Specific Gravity of Silver Arsenate. 



In order that the apparent weight of the silver arsenate might be 

 corrected to a vacuum standard, the specific gravity of the arsenate 



was found by determining the weight of toluol displaced by a s known 

 quantity of salt. The toluol was first dried by means of stick soda and 

 was then distilled, with rejection of the first portion of the distillate. Its 



