ATOMIC WEIGHTS 209 



be contaminated with traces of lime derived from a glass tube. They 

 finally resorted to the crystallized siilphate as the most available salt 

 for their purposes. This compound, upon strong ignition, yields pure 

 glucina. The data are as follows : 



0023 



Hence Gl = 9.113. 



Kriiss and Moraht ' in their work followed the general method adopted 

 by Nilson and Pettersson, but with various added precautions and greater 

 elaboration of detail. Their glucina was derived from three sources, 

 namely, leucophane, beryl and gadolinite, and the sulphate was repeat- 

 edly recrystallized. The results are subjoined: 



G1S0,4H.0. GIO. Per cent. GIO. 



21.1928 3.0008 14.160 



16.2038 2.29455 14.161 



15.49345 2.1902 14.136 



20.1036 2.8433 14.143 



22.0465 3.1167 14.137 



4.9619 .7019 14.146 



18.3249 2.5921 14.145 



24.3907 3.0253 14.143 



20.18045 2.85255 14.135 



20.0253 2.8328 14.146 



18.9840 2.6832 14.134 



17.0072 2.4073 14.155 



22.5044 3.1805 14.133 



20.88675 2.95645 14.1.54 



19.0591 2.69305 14.130 



17.8227 2.5226 14.153 



]\Iean, 14.144, ± .0017 



Hence Gl = 9.062. 



The first two determinations, which give the highest percentage, were 

 made upon sulphate thrice crystallized. The others were made upon a 

 salt four times crystallized, except in one instance, when there were five 

 crystallizations. To the data derived from the four times crystallized 

 compound Kriiss and ^Moraht give preference, and so find a slightly lower 



1 Ljebig's Annalen, 262, 3S. 1891. 



