OBSERVATIONS ON THE TREMOHTE. 2.95 



gent rays, tranfverfely crofied by other fibres, fo as to repre- 

 sent a kind of texture, as is fometimes the cafe with the zeo- 

 lite mezotipe. This trernolite is of a greenifli white colour: 

 it adheres to a granulated but very compacl mafs of carbonate 

 of lime, mixed in almoft equal proportions with the fame tre- 

 rnolite, alfo in a granulated flate, on which account it ftrikes 

 fire with fteel. This carbonate of lime pouefles both kinds of 

 phofphorefcence, but the light which it gives is of a (lightly 

 blueifh colour ; the fame is the cafe with the trernolite which 

 it contains. This carbonate does not belong to the dolomie, 

 and it diflblves in acids in the fame manner as the common 

 carbonate of lime. 



The trernolite of Vefuvius is likewife in the fibrous ftate, Trernolite of 

 with fine and clofe fibres ; its colour is a greyifli white, it Mount Vefu- 

 adheres to a gangue compofed of carbonate of lime, of an im- 

 menfe quantity of very fine fmall fibres of the fame trernolite, 

 and of a great number of very fmall cryftals of pyroxene, of a 

 beautiful green colour and tranfparent. Some portions of ido- 

 crafe are alfo obfervable, of which there is a group at one of 

 the extremities of the fpecimen in pretty large cryftals. The 

 carbonate of lime does not belong to that of flow folution ; it 

 poflefles both kinds of phofphorefcence, and the light which 

 it emits is of a very lively deep orange colour. The trernolite 

 exhibits abfolutely the fame phofphorefcence. 



We owe our knowledge of the trernolite of Bengal to Sir Trernolite of 

 John Murray. It is in pretty large cryftals of a greenifli grey Bengal* 

 colour, bedded feparately in a granulated carbonate of lime, 

 the very fine grains of which have a ftrong adhefion to each 

 other j a character which, joined to the great whitenefs of this 

 ftone, caufes it very much to refemble a piece of double re- 

 fined fugar. This carbonate of lime belongs to the fpecies of 

 the dolomie; it is even one of thofe in which I have obferved 

 the folution to be the flowed and moit infenfible, but it is ne- 

 verthelefs completely dilfolved in the nitric acid, leaving only 

 a light whitifh and clouded refidue, which difappears when 

 the acid is diluted with water. Its hardnefs, which is much 

 fuperior to that of the ordinary carbonate of lime, is rather 

 inferior to that of the fluate of the fame earth ; and this is the 

 cafe with all the dolomies, not excepting thofe whofe grains 

 have the leaft adhefion with each other. This dolomie is not 



phofpho- 



