ACCURACY OF NEUMANN’S METHOD. 93. 
4, The error is independent of the time of contact between 
the precipitate and the mother liquor. 
5. The error cannot be reduced by lowering the temper- 
ature of precipitation, as this leads to incomplete precipi- 
tation. 
In conclusion I wish to express my thanks to Professor 
Anderson Stuart, in whose laboratory this work was done, 
and to Assistant-Professor Chapman for his advice and 
encouragement. 
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