﻿1903] 



CHEMICAL STIMULATION 



93 



to form a visible precipitate, this was allowed to settle, and the 

 solution then siphoned into C. As one-third of the baryta water 

 used was ordinarily more than was needed for titration, I was 



OXALIC 

 ACID 





1 



I 





Fig. 2. 



nmg to measure it. 

 "burette" D. which 



able to use it freely in washing out the apparatus before begin- 



For the actual measurement I used the 

 I blew from heavy tubing with a bore of 

 less than 3'"'°; from the scratch above the bulb to that below is 

 exactly io<=^ The titrating was done in 100'='= bottles, with per- 

 forated corks. Two drops of neutral alcoholic phenolphthalein 



