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May 16, 1849. 

 The President in the Chair. 



Present, twenty-one members. 



Dr. Bacon read a paper by Mr. T. S. Hunt, of tho 

 Geological Commission of Canada, on a new mineral, foi 

 which he proposed the name of Algerite. 



This mineral occurs in Franklin, N. J., imbedded in a white 

 crystalline limestone. The crystals are sometimes three inches 

 in length, and rarely more than one eighth of an inch in thickness. 

 They are frequently curved, like Sillimanite and Scapolite. 

 Color brownish, yellowish white, or straw yellow, sometimes with 

 a greenish shade. They are translucent, with a vitreous lustre. 

 Some specimens bear a striking resemblance to Chondrodite, 

 with which the mineral was at first supposed to be identical, 

 when found in a few fragments. It has also been referred to 

 Scapolite and Spodumene. Prof. Nuttall was the first mineral- 

 ogist who expressed the opinion that it might be new, but he did 

 not enter into any investigation of its characters ; and for the 

 last ten years it has been overlooked, until recently brought to 

 light and examined in better specimens by Mr. F. Alger, whose 

 description of its physical characters is copied by Mr. Hunt. The 

 form of the crystals is an oblique rhombic prism, the angle of M 

 on M^ being about 94°, as determined by the common goniome- 

 ter. The terminal and basal planes, although plainly indicated, 

 are not sufficiently distinct for measurement. The only modifi- 

 cations observed are replacements of the oblique and lateral edges 

 of the prism by single planes. The specific gravity is 2.785 

 (Hunt,) and the hardness 3 — 3.5 (Alger,) or less than that of 

 fresh crystals of Laumonite. 



Its analysis afforded Mr. Hunt the following results: — 

 Silica 49.82, alumina 24.91, peroxyd of Iron 1.S5, magnesia 

 1.15, potash 10.21, soda-traces, water 7.57, carbonate of lime 

 3 94, The composition of the mineral, deducting the carbonate 

 of lime, which appears to be derived from the matrix, is a 

 hydrafed silicate of alumina and potash, in which small quantities 



