SUMMIT OF PARNASSUS. 265 
crystallization'^', but the observation had not been chap. 
extended to bodies considered as amorphous. 
Nothing is more common, however, than the 
primary angle of crystallized silica, among the 
fragments of common quartz, when found in the 
form of sand or gravel ; of the primary angle of 
carbonate of lime, in the fracture of a shell ; or, 
upon a much grander scale, in the fissures of 
beds of chalk, as in the clitfs upon the south 
coast of Britain ; also of the primary angle of 
corundum in the fracture of emery; together 
with many other examples that might be 
adduced, all of which would be rather out of 
place here. The author, indeed, apologizes for 
the little he has been tempted to introduce 
upon the subject, owing to his predilection for 
a favourite branch of Natural History; and 
believing, as he does, that if more attention 
were given to the circumstance, it would not 
only be serviceable to the science in general, 
but to the purposes of commerce, as connected 
with the sale of precious minerals, and with 
mining speculations. 
(2) Witness the surprising discovery of Haul/, and his theory of 
crystallization thereon founded. Also the observations of our own 
IFbllaston, Secretary of the Royal Society, and his valuable invention 
of a reflecting goniometer, as applied to the inclination of surfaces 
disclosed by fracture, where crystallization has taken place. 
