Prof. Maskelyne and Dr. Lang's Mineralogical Notes. 53 



fell at Bulloah are small fragments, fitting on, as before men- 

 tioned, to one of the long edges of the Piprassi stone. Probably 

 the whole five formed a long bar-like piece fitting on to that 

 edge, and these two would, in that case, constitute the half of it. 



The Bulloah stones (numbered 1 and 2 in the figures on 

 Plate IV.) are rounded along their summits and sides, and 

 are there coated with a crust of a sooty black, and of dense 

 texture. On the surface of contact they and the Piprassi are 

 not crusted. The material of which the interior of the Bulloah 

 stones is composed proves, when examined by a lens, to contain 

 a profusion of protruding points of metallic iron. It presents a 

 yellowish-brown ground-mass. It is mottled with irregular 

 dark stains, which surround the metallic iron. This iron, asso- 

 ciated with a considerable amount of meteoric pyrites, is present 

 in this aerolite to a very high percentage. It is very evenly 

 distributed in small, isolated, irregularly formed and sometimes 

 crystalline-looking particles, not aggregated into a sponge, as in 

 the siderolites, but, as in the beautiful aerolite of Akbarpur, the 

 grains of metal seem linked by a ferruginous or iron-stained 

 mineral, which may possibly indicate the vestiges of a sponge- 

 like structure of the iron at some earlier period in its history, 

 when perhaps the silicates were less basic than at present, and 

 less of the iron oxidized. 



Besides these ingredients, there are several very irregularly- 

 distributed spherules of a mineral of the greenish-brown colour 

 and translucency, as well as the lustre, of dirty bees-wax. It is 

 somewhat transparent in thin sections, and presents the charac- 

 ters of olivine. 



A minute amount of iron pyrites occurs besides the meteoric 

 pyrites ; and a little of a very dark-coloured mineral is also pre- 

 sent, generally with a lustrous fracture, and perhaps occasionally 

 somewhat crystalline. 



ft In a section under the microscope with a power of one-inch 

 focus, this aerolite does not prove to be a very remarkable one. 

 The mass of it seems to consist of olivine. This is associated 

 with a grey mineral, and also with one that is of an opake white. 

 This grey mineral in some cases seems to constitute entire no- 

 dules of the aerolite, and sometimes seems mingled in the sovt 

 of brecciated mass, containing olivine crystals, that forms other 

 nodules in it. It presents the appearance, in the former case, 

 either of a dark mottled surface spangled with dark points (con- 

 sisting sometimes of iron, and in some cases curiously distributed, 

 as if spurted through the mass from a centre), or of a mineral 

 presenting very regular and minute parallel cleavage-planes 

 with dark grey bars running aloug them, often rayed out like a 

 fan, and with cross cleavages usually oblique, but at angles 



