VI PREFACE. 



Mineralogy and the publication of ROBINSON'S Catalogue, 

 and so many doubtful points existed in relation to many of 

 those quoted in these works not a few having been erro- 

 neously announced, either through inaccurate determina- 

 tions of the species, or their occurrence in trifling and ac- 

 cidental quantitity that the proposed work seemed justi- 

 fiable solely on this ground, provided there was a reasona- 

 ble hope of placing the subject in a more just light. Be- 

 sides, it was had in view to indicate the crystalline forms 

 noticeable among our minerals, a point which had been so 

 much overlooked as to have created a very unfavorable 

 impression of the mineralogical riches of the country. 

 There seemed room also, to perform a desirable service 

 by appropriating to the work the latest discoveries of the 

 German mineralogists, to whom the science is indebted for 

 its most important advances during the last ten years. 



The general rules according to which the descriptions 

 have been drawn up, are those laid down in . 126, of the 

 Introductory volume- The trivial names to the species 

 having been adopted in the analytical tables for the reasons 

 given in 117, it became necessary to employ them also 

 in the present work. Indeed so small is the number of 

 species in the mineral kingdom compared with the species 

 in the other departments of Natural History, and so defi- 

 cient in fixity are many of the still accounted species, that 

 it is, and probably for some time to come will be, most 

 prudent to call them by these names- The chemical de- 

 signations having by general usage been dropped where 

 other names existed, BF.UDANT in his system of Mineralo- 

 gy has attempted by the invention of new names, where 

 it was necessary, to render universal the application of the 



