32 



[Senate 



17. Potsdam sandstone, with spherical concretions. Vicinity 



of the Caledonia or old Parish iron mine, Rossie, St. Law- 

 rence county. 



18. Serpentine and steatitic pyroxene. Village of GouvemeuT, 



St. Lawrence county. 



19. Sphene (black) in crystals, imbedded in Gneiss. Near Gouv- 



erneur village, St. Lawrence county. 



20. Calcareous spar. Banks of Vrooman's lake, Antwerp, Jef- 



ferson county. 



21. Iron sand, (magnetic.^ Shore of Buonaparte's lake, Diana, 



Lewis county. 



22. Cast of the labrum of an Isotelus. Found in Ohio. 



23. Dodecahedral crystals of sulphuret of iron. Farm of 



John Robinson, Gouverneur, St. Lawrence county. 



24. Cubic crystals of sulphuret of iron. Same locality. 



25. Spinelle, (pale red.) Farm of Mr. Ayers, Gouverneur, near 



Somerville, St. Lawrence county. 



26. Calcareous tufa. Martinsburgh, Lewis county. 



27. Crystalized mica. (5 specimens.) Vrooman's lake, Antwerp, 



Jefferson county. 



28. Minute capillary crystals of sulphuret of nickel ? Found 



on Ankerite, and associated with Cacoxenite. Sterling 

 iron mine, Antwerp, Jefferson county. 



29. Potsdam sandstone, (cylindrical structure.) Rossie, St. Law- 



rence county. 



This curious structure is frequently observed in this section of the 

 country, and I do not recollect of having seen a satisfactory theory 

 to account for its formation. These cylindrical masses are of all sizes, 

 from three inches, to fifteen or twenty feet in diameter ; and their axes 

 are always nearly, if not exactly vertical. At times, two or more en- 

 croach on each other. 



The large circle represented in the following figure, is about twelve 

 feet in diameter, at the locality in Somerville, and the whole is nearly 

 of the same level. The concentric lines of stratification are sometimes 

 obscure, but the cylindrical structure is always sufficiently apparent. 

 To no active agent can we attribute these interesting appearances with 

 more plausibility, than that of water, revolving in the little vortices or 

 eddies, and causing the sand, which is the principal constituent in the 



