‘ 
S. L. Penfield—Chemical Composition of Childrenite. 315 
tion flow, as the force of rotation would impel them. A lan- 
Art, XXXIX.— On the Chemical Composition of Childrenite ; 
by 8. L. PENFIELD. 
AFTER the publication by Messrs. Brush and Dana* of their 
paper in which the new species, eosphorite, was described and 
shown to be closely related both physically and chemically to 
childrenite, they proposed to me to make a new or 
tion of the composition of the latter species with a view to de- 
ciding the uncertainty in regard to its true formula. Professor 
Brush very kindly placed at my disposal a suitable specimen 
tom Tavistock out of his collection. From this the ma- 
terial for the following analysis was taken. The crystals were 
small, of a yellow-brown color, and were very carefully picked 
* This Journal, July, 1878, 
