2S2 Count de Bournon's Description of 
may be perceived, here and there, some small particles, in which 
an incipient laminated texture is discernible. These particles 
are rendered visible by the reflection from the laminae ; they 
are of a beautiful rose colour, and have a slight degree of trans- 
parency. The lens also shows, at the same time, a great 
number of small globules, of a deep black colour, and of a very 
brilliant lustre : these globules do not consist of attractable oxide 
of iron, although that oxide is very common in the substance 
here treated of ; but, on account of their small size, it has not 
yet been possible to determine their nature. 
The compact corundum of a red colour gives pretty strong 
sparks, when struck with steel ; it also gives, by collision, the 
same phosphorescent fiery red light as the other red varieties of 
corundum, both perfect and imperfect. 
The mean specific gravity of compact corundum, taken from 
three trials, which differed very little from each other, was 
■ 39 °®- 
MATRIX OF IMPERFECT CORUNDUM FROM THE PENINSULA OF 
INDIA, AND CHIEFLY FROM THE CARNATIC. 
This matrix, which, as far as our present knowledge extends, 
appears to be peculiar to the imperfect corundum of this part of 
Asia, is a stone of a particular nature : it is sometimes in masses 
of a loose and granulated texture, with very coarse grains, and 
pretty much resembles a coarse sand stone ; at other times, it has 
a closer texture, the grains being nearer each other, and less 
distinct, so as either to give it an appearance similar to the kind 
of marble known by the name of coarse-grained saline marble, 
.or to that kind of prehnite which is composed of a mass of 
