Miscellanies. 191 



16. Evidences of diluvial currents — petrifactions — metallic models of 

 shells. To Prof. Silliman & Son : Gent., — Herewith I send you speci- 

 mens of the surface rock in this vicinity. The large slab, containing 

 chert, was taken from the village of Black Rock, about four miles north 

 of this city. The grooves at this locality, as determined by Mr. Haskins 

 and myself, range, allowing for variation, N. 2S^ 12' E. 



You will perceive, that wherever a nodule of chert projects above the 

 surface, a ridge of the softer limestone has been protected,- in some 

 measure, from friction, which invariably, at this locality, as well as at the 

 Black Rock quarry, one and a half miles distant, point in a southerly di- 

 rection. Some parts of the surface rock, where this slab was procured, 

 present this phenomenon much more perfectly ; the nodules of chert 

 often having a semi-circuiar depression worn into the rock on their north- 

 ern sides, opposite to the projecting ridge. I regret that such a specimen 

 could not be procured, as the strata on which they occur are from one foot 

 to one and a half feet in thickness. 



Can proof be more conclusive, that these marks and scratches were 

 produced by gravel stones and boulders, swept over the surface of the 

 rocks by currents, tides, or waves, which flowed from the north ? 



I also send a smaller slab, somewhat polished. It was procured about 

 half a mile further north, but as no marks appear on the surface, we 

 could not determine precisely the course from which the water flowed. 



At Black Rock quarry, where a large surface has been uncovered for 

 the purpose of procuring materials to construct the breakwater, outside of 

 Buffalo harbor, the grooves range N. 15° 33' E. The friction there has 

 been equally powerful ; but as the rock consists almost entirely of chert, 

 the ridges pointing towards the south are less prominent. 



I also put into the box a piece of weathered chert, from which the car- 

 bonate of lime has been decomposed. The workmen here sometimes 

 call this "chawed stone." I add also some madreporites, and metallic 

 casts of two species of terebratulites, of which I have been able to procure 

 but single specimens. 



Hoping that the box and its contents will prove acceptable, I remain, 

 yours truly, &c. Geo, E. Hayes. 



The box was highly acceptable, especially as the proofs of powerful 

 and lasting diluvial action are decisive on the slab of limestone, as well 

 as on the pieces which we have recently seen at Buffalo, in the possession 

 of Mr. Haskins and Dr. Hayes. — Editors. 



17. The American Almanac, and Repository of Useful Knowledge, 

 for the year 1839. Boston, Chas. Bowen. Vol. 10. — This valuable work, 

 for the ensuing year, has been forwarded to us by its Editor, Mr. J. E. 

 Worcester. To it is appended a general index of the last ten volumes, 



