MODE x. ALABASTER. 499 



soft to be polished. It may also, like that near 

 Nottingham, appear blue when held between 

 the eye and the light. 



It is now proper to pass to the consideration 

 of that fine compact gypsum called alabaster. 

 This substance, like alabastrite, is regarded as 

 being a sinter , or deposition; but from gypsous 

 rocks. Hence it is commonly found in small 

 layers, and being rather soft, is used for little 

 statues and ornaments. Yet Gmelin, who has 

 ranked it under gypsum, assures us that it forms 

 entire mountains, or at least very large strata, in 

 Thuringia and Siberia*; but he probably con- 

 founds it with alabastrite, the ancient or cal- 

 careous alabaster. If, as Mr. Kirwan asserts, 

 even mountains of gypsum are foundf, alabaster 

 may fill prodigious caverns. While Werner and 

 his disciples are perhaps too minute in lithology 

 and metallogy, they are in petralogy far too 

 theoretic and general : but if gypsum be found, 

 as they assert, in rocks distinguishable by their 

 white colour, they must belong to alabaster. 

 In fact, what has been styled primitive gypsum, 

 particularly the cubic of Salins, Mont Blanc, is 

 the purest alabaster; and naturalists ought to 

 attend to common distinctions, and the purposes 



* Linn. 118. 



t Geological Essays, 238. 



2 K2 



