2i30 Miscellaneous Notices in Mineralogy, Geology, ^-c, 



shall both be gratified if we can add any thing to the stock 

 of useful knowledge by the best observations we can make. 



3 Lime for water Cement. 



The following notice of the lime used in the sub-aqueous consti'uctions of 

 the great canal in the state of New-York, we owe to the kindness of W. W. 

 Woolsey, Esq. The specimens alluded to have been received, but we have 

 not yet been able to subject them to any experiments. 



Extract of a letter from Benjamin Wright, Esq. chief Engi- 

 neer of the Erie Canal, to W. W. Woolsey, Esq. of 

 New-York, dated Rome, June 24, 1820. 



Dear Sir, 



The specimen of Argillo-ferruginous limestone, herewith 

 presented, is found in great abundance in the counties ot 

 Madison, Onondaga and Cayuga, in the state of New- York. 

 When found in place, it is always under the blue lime, which 

 is uniformly overlaid with grey lime. The grey is the up- 

 per stratum, and is found in large heavy blocks ; the whole 

 six or eight feet in thickness. The blue which next occurs, 

 is various in thickness, and from it is made the beautiful 

 white lime. Under the blue hes the first described, which 

 is found to be a superior water cement, and is used very 

 successfully in the stone work of the Erie canal, and believ- 

 ed to be equal to any of the kind found in any other coun- 

 try. I cannot give you the analysis — if convenient to give a 

 sample to Mr. Silliman for his examination, it might be use- 

 ful to the community to have its properties fully understood, 

 and if he thinks it merits a place in his useful publications 

 I presume he will give it. I do not know that it is found in 

 the counties west of Cayuga, but presume from the geolo- 

 gical character of that county it may be found in all the 

 country west to Niagara, and probably further west. It is 

 pulverized (as it will not slack) and then used by mixing two 

 parts lime and one part sand. It hardens best under water, 

 and it is believed its properties are partially lost if permit^ 

 ted to dry suddenly, or if not used soon after mixing. 



Mr. Canvass White, a friend of mine, has obtained a pat- 

 ent for it when used for hydraulic purposes, and it is be- 

 lieved it will answer an excellent purpose for rough casting. 



