Arrangement ofMinerah. 383 



You have further co-operated materially in advancing our in- 

 quiries, by your personal assistance, at all times cheerfully 

 and liberally rendered to all your fellow-labourers, in the same 

 field of scientific research, who stood in need of yoiu- aid, for 

 the elucidation of minute distinctions in the characters of fos- 

 sil organic remains, which have at this time become so im- 

 portant an element in geolog\\ The volumes of the Transac- 

 tions of this Society, and other publications by many of its 

 members, including myself, bear further testimony to the va- 

 lue of your labours in illustrating our works with drawings and 

 engravings of fossil shells and plants, expressing their charac- 

 ters with a degree of accuracy and truth, which no pencil or 

 burine but those of a scientific artist could possibly accom- 

 plish ; and I am sure I give utterance to the feelings of many 

 of our fellow-labourers, now around me, when I thus publicly 

 acknowledge the services you have rendered, both to ourselves 

 and to the science we cultivate ; and testify our satisfaction 

 at the present public recognition of your valuable services by 

 the Geological Society of London." 



Arrangement of Minerals, founded upon Physical and Che^ 

 mical Characters. 



CLASS I. 



Characters of the C?airs.— Specific gravity less than 3.a. 

 No bituminous smell. If solid is sapid. 



Order I. Gas. Order II. Water. Order III. Acid. Order IV. 



Salt. 



CLASS II. 



Characters of the CVass.— Specific gravity more than 1.8. 

 Tasteless. 



A. — Haloidal Minerals. 



Tasteless compounds of Earths and Acids, and of Metals 

 and Acids. 



