52 



gentlemen, Profe 



April 5. The following donations were received : — Bitu- 

 minous coal from Nova Scotia, from George W. Feather- 

 stonhaugh; favosite from (Mean Point, and anadonta margi- 

 nata, Erie canal, from James Geddes ; cast of an encrinite, 

 from the upper part of the Susquehannah, from Joseph Henry ; 

 two copies of a " Memorial on the upward forces of the fluids, 

 &c." from Edmond C. Genet, the author. 



Dr. T. Romeyn Beck made some remarks on the analysis 

 of the impure limestone (hydraulic lime) used in the con- 

 struction of the locks of the Erie canal. 



This substance is found in large quantities in the western 

 part of the state of New- York. Its properties attracted at- 

 tention shortly after the commencement of the excavations on 

 the western route of the canal, and at the request of several 

 fessor Had ley undertook a hasty analysis of it, 

 s noticed by him, were as follows : — 

 Carbonic acid 35.05 



Oxide of iroa 2.02 

 98.21* 



Mr. Henry Seybert published an analysis of this 

 stance, in the second volume of the Transactions of 

 ican Philosophical Society, new series, p. 229 viz 

 Carbonic acid 39.3 * 



Silica n.7 

 Alumine 2.7 

 Peroxide of iron 1.5 

 Lime 25.0 

 Magnesia 17.8 



Mr. Seybert remarks, that it is evident that Dr. Hadlev 

 overlooked the magnesia which forms an essential constituent 

 of this mineral. 



The object of the remarks of Dr. B. was to introduce the 

 following observations of Professor Eaton, contained in hi* 

 Geological Survey of Albanv countv, p. 20. "We analy- 

 zed a specimen (of water limestone) from the Helderbenrh, 

 but by a method which is not deemed the most accurate, and 



