CLARKK AND"! . 
BTEIGER. J 
CONSTITUTION 
OF ANALCITE. 
Si0 4 =K 2 
Si0 4 =Na 2 
\ai- 
Al Si,O s =K 2 
-SiO„ 
=A1. 
yAl— Si0 4 = A I. 
Al 7 Si i Os=Na, +ni.() 
Si :! 8 =Al 
Si.Ox^Al 
Leu cite. 
Analcite. 
25 
That is, analcite and lencite become members of the garnet-sodalite 
group of minerals, and their relations to nephelite, albite, prehnite, 
natrolite, etc., natural and artificial, are perfectly clear. In analcite 
there may be admixtures of strictly analogous ortho- or trisilicate 
molecules; but these remain to be separately discovered. 
Now, these formula? are not ultimate verities to be blindly accepted. 
They are siinjdy expressions which represent composition and a wide 
range of established relationships, and which serve a distinct purpose 
in the correlation of our knowledge. Properly used, with due recogni- 
tion of their limitations, they are helpful, and suggest possibilities of 
research; misused, they may become mischievous. They now satisfy all 
known conditions, and that is a sufficient warrant for their existence. 
