300 MR HAIDINGER on the Determination of the Species in 



ness has been rather the consequence of a more intimate ac- 

 quaintance with nature, than the result of applying philoso- 

 phical principles to observation. The application of geometry 

 in the consideration of forms, imparted precision to a pro- 

 perty which had hitherto been as vague and uncertain as others 

 The striking contrasts offered by the forms of different species 

 being once recognised, it became almost impossible for HAUY, 

 and subsequent crystallographers, to fall into the same errors 

 which render the systems of an earlier period useless. The cry- 

 stallographic method of WERNER was far from affording preci- 

 sion and security, in its determinations ; and his species, there- 

 fore, are less correctly circumscribed than those of HAUY, who, 

 notwithstanding the great superiority of geometrical evidence to 

 that of mere inspection, considered the introduction of a chemi- 

 cal principle into the determination of the species as unavoid- 

 able. Although chemistry has always exercised a great influ- 

 ence upon the methods received in mineralogy, it cannot be said 

 that this was more particularly the case in respect to the esta- 

 blishment of the idea of the species, when it even required the 

 sagaeity of ROME' DE L'!SLE to demonstrate that there really 

 were such things as true species in the mineral kingdom, which 

 till then was denied by the chemists of the day. The Werne- 

 rian System demonstrates, in every one of its departments, that 

 it has in fact no principle upon which it might be said solely to 

 depend ; and the characteristic ingredient itself may be ambigu- 

 ously interpreted. This want of unity in the principle of the 

 Wernerian system, has perhaps nowhere been more plainly ex- 

 pressed than in the first edition of Professor JAMESON'S System 

 of Mineralogy, where we find the following passage : " The Wer- 

 " nerian oryctognostic system is founded solely on the natural 

 " alliances and differences observable among minerals. But on 

 " what do these depend? WERNER answers, on the quality, 



