MODE V. GRANITE. 137 



passes to the bottle green, through the brown; 

 afterwards loses its colour, and dissolves with 

 some effervescence, which proves there is a mix- 

 ture of magnesian earth. 



" The earthy steatite, which also forms a very 

 inconsiderable part of the mass of these granites, 

 resembles that of 1987. 



" All these granites have their natural divi- 

 sions covered with some coat, either green or 

 blackish. This is an earth like chlorite, of a 

 green almost black, and a little shining on its 

 external surface, but of a more bright green and 

 earthy in its fracture; soft, scratching with a 

 greenish grey streak ; at first turning brown un- 

 der the blow-pipe, then yielding a knob = 0,3, 

 or fusible at the 189th degree of Wedgewood. 

 This knob has a metallic aspect, somewhat un- 

 equal, and a little dull, like that of bars of melted 

 iron; and not only the knob, but all the parts 

 that the action of the flame renders brown, are 

 strongly attractable by the magnet. A small 

 fragment tried upon the rod of sappare, at first 

 infiltrates like ink between its fibres, then be- 

 comes of a dull brown, and at length entirely 

 discolours, but without any appearance of dis- 

 solution. 



" The green coat which covers other pieces 

 of these granites in their spontaneous divisions, 



