305 [Douton. 



Virginia, Nevada, February 10th, 18G6, acknowledging their election 

 to Corresponding Membership. 



The following gentlemen were elected Resident Members : 

 Dr. J. H. Warren, Messrs. AY. E. Boardman, C. P. Putnam, 

 Edwin Bnrgess of Boston, and Mr. Frank C. Garbutt of 

 Cambridge. 



March 7, 1866. 

 The President in the chair. 



Forty-two members present. 



The following communications were read : 



Ox A Mineral, eesemblixg Albertite, from Colorado. By 

 Prof. William Dextox. 



When on an exploring trip west of the Rocky Mountahi Rano-e, in 

 July of last summer, I found, near the junction of White and Green 

 Rivers, and probably in Utah, a series of tertiary beds of brown 

 sandstone, passing occasionally into conglomerate, and thin beds of 

 bluish and cream-colored shale alternating with the sandstones. 



These beds dip to the west at an angle of about 20°; and croppino- 

 out from beneath them on the east, are beds of petroleum shale, a 

 thousand feet in thickness, varying in color from a hght cream to inky 

 blackness. One bed, ten feet in thickness, which I traced for six 

 miles, is scarcely distinguishable from the best cannelite of Xew Bruns- 

 wick. In the sandstone overlying the shales, I found a perpendicu- 

 lar vein of bitumen resembling in lustre, fracture, and other physi- 

 cal characters, pure Albertite. This vein has a width of from two 

 feet six inches, to three feet four inches ; it lies between smooth walls 

 of sandstone, and was traced by us for a distance of five miles in a 

 nearly direct line, due west. Two more small veins were discovered 

 parallel to the first, one south, and the other north, and each distant 

 about a mile. 



The sandstone has been eroded by water into ravines and canons 

 to a depth of from eight hundred to one thousand feet, and the princi- 

 pal vein can be traced from the top of the mountain to the bottoms 

 of these canons, retaining its width, but not apparently increasing it. 

 In the sandstone I found fossil wood of deciduous trees, fragments 



rPvOCEEDIXGS E. S. >". H.— VOL. X. 20 JUXE, 1866. 



