Geological Survey of the State of New York. 73 



Prehnite generally accompanies the Thomsonite, and some- 

 times the datholite. A vein of Thomsonite with this mineral oc- 

 curs between Nos. 9 and 10, but it is difficult to procure any thing 

 from it. A specimen of prehnite and Thomsonite, presenting a 

 surface about three or four inches square, found loose, is of great 

 beauty — the latter in long, transparent crystals, radiating through 

 the former. 



Blende, imbedded in apophylhte, has been obtained here — the 

 quantity very small ; colors green and red. Galena, in small crys- 

 tals, of which only a specimen or two was found. 



Among the loose bowlders to be met with in the soil where the 

 excavations were made, was one from which some good speci- 

 mens of idocrase were taken. 



Scolecite, I think, may also be included in the list of the mine- 

 rals of this locality, a specimen in my collection answering the 

 description by Dana in its external characters. 



Dr. Beck, in his last report on the mineralogy of New York, 

 states that he visited Bergen Hill, and found stellite there. He 

 also appends to his report Dr. Thomson's description of the mine- 

 ral. Since reading it, I have re-examined my own collection, 

 and have little doubt that I had previously confounded the stel- 

 lite with Thomsonite. 



The greenstone ridge, in which the veins just described occur, 

 is two miles from Jersey City, the mile post being placed near 

 the middle of the cut. This is the principal one of three ridges 

 which are covered with soil, although they are in some places 

 denuded, and the valleys between them filled with bowlders and 

 sand, which, doubtless, have been deposited there by diluvial ac- 

 tion ; but I leave these interesting speculations for others. 



Art. yn. — Notice of the Geological Survey of the State of New 

 York, presented to the Legislature, Jan. 24, 1840 ; by Oli- 

 ver P. Hubbard, M. D., Prof, of Chemistry, Mineralogy and 

 Geology in Dartmouth College, N. H. 



The steady progress which has attended the geological survey 

 of New York, must be gratifying to every friend of science and 

 of popular improvement. These annual reports are intended only 

 as evidence to the proper authorities of the State of the advance 



Vol. XL, No. 1.— Oct.-Dec. 1840. 10 



