and Skepard's Treatise on Mineralogy. 335 



mineral, and as affording the most simple arrangement ; and then 



proceed to such as, by the most authentic analyses, appear to 



consist chiefly of silica. Those of which alumina forms the 



greatest proportion succeed, as being the earth next in age and 



abundance. Magnesia follows ; then such minerals as consist 



primarily or in part of zirconia or glucina, or lastly of yttria and 



thorina." Independently of the loose principles of arrangement 



here laid down, it sounds like the fancies of days long gone by, 



this making silica the "oldest" mineral, and alumina " next in 

 age !" 



The work begins with the species in the following order : 



Quartz 



Heulandite, Davyne 



zoisite, epidote, &c. ; a strange commingling of minerals, whether 

 we consider the principles of chemistry or natural history. From 

 quartz and opal, the first transition is to Icarpholitc, a hydrous 

 silicate of alumina and manganese ; next to alumocaltite, a variety 

 of opal ; then to the complex anhydrous earthy mineral garnet: 

 soon follows Prehnite, stilbite, Heulandite, &c, hydrous species ; 

 and then the wanderers, zoisite and epidote. 



Take another place in the system, where we find the following 

 order, (p. 192, &c.) — Feldspar, ryacolite, petalite, spodumene, 

 Latrobite, agalmatolite, glaucolile, mesotype, Thomsonite, Peris- 

 terite, leucophane, mesole, &c. After feldspar and ryacolite we 

 find nothing of the other feldspar minerals, anorthite, albite, 

 &c., so ably investigated by Abich ; these occur many pages 

 °ff: but there follows spodumene, and soon after, the zeolites, me- 

 sotype and Thomsonite; next, Thomson's Peristerite, (nothing 

 but an iridescent feldspar from Perth, U. C. ;) after this, another 



zeolite, mesole. 



Eloiolile is followed by Hi 



then hydrous anthophyllite, a hydrous mineral near steatite in its 

 characters ; next antrimolite, a zeolite ; Pericline, one of the feld- 

 spars, (which by the way has been shown of late by Gmelin to 

 be identical with albite ;) Labradorite, albite, other feldspar min- 

 erals; and then the hydrous silicate, analcime. There is still 



appearance 



a, s contain an alkali. Such incongruous connections prove the 



adop 



classification. 



upon 



