we 
Messrs. Johnson and Blake on Kaolinite and Pholerite. 355 
a pearly luster. Dr. Genth remarks that under the microscope 
the scales appear to be clinorhombic. His analysis of this sub- 
stance, after purification by hydrochloric acid, is given below. 
.. The first mention of a crystalline substance with the compo- 
sition of Mrchhammer’s kaolin that we have been able to find 
_ is by Wohler, who describes, under the name steinmark, a pale 
yellow coherent mass which is converted by dilute hydrochloric 
acid, with solution of a little oxyd of iron, into a white shining 
powder. (Ann. d. Ch. u. Ph., lxxx, 122.) With help of a lens, 
Wohler found it to consist of ‘shining lamin, which, when 
assumed luster by rubbing, an unctuous feel, and adhered 
strongly to the tongue. Sp. gr. 2:6.” The locality was Schneck- 
enstein, Saxony. The analysis by Prof. W.S. Clark, now ‘of 
Amherst College, is given below. 
n response to our application, Prof. Clark has kindly favored 
! that it re- 
Schl 
form of brilliant white seales, which is obviously 
(Jour, 
In 
; ineral ana y Pisani the same | 
ty (Comptes Rendus, liii, 1072, also Dana’s 10th Suppleme 
