so Chemical Examination of Harmotome. 



98* 96-5t 98-91 J 99-09<§ 



It IS probable that the barytes-harmotome, is a compound 

 of, 



1 atom bisilicate of barytes, 

 4 atoms bisilicate of alumina, 

 3 atoms water. 



If the constitution of the lime-harmotome be similar, there 

 is a deficiency of lime in the specimen analyzed by Werne- 

 kink. In the Strontian harmotome, the barytes, lime, and 

 potash, seem altogether to make up the quantity of one 

 atom. 



29. THOMSONITE. 



This mineral was constituted into 'a peculiar species by 

 Mr. Brooke ; and 1 published a chemical analysis of it in 1820, 

 in the l6th volume of the first series of the Annals of Philoso- 

 phy, from which 1 deduced its composition to be, 



* Klaproth, Beitrage, ii. 83. From Andreasberg. 



f Tassaert, Hauy's Tableau compar. p. 201. 



I Wernekink ; Gilberl's Annalen, Ixxvi. 175. From Scbiffenberg- 



s Ibid. From Annerode. 



