1887.] NEAV YORK ACADEMY OF SCIENCES. 91 



Mr. Chittenden stated that litigation over patents had de- 

 "veloped the fact that driven wells were first used practically by 

 the Union armies during the war of the rebellion. 



The subject was further discussed by Prof. J. J. Stevenson, 

 Mr. Chittenden, Mr. Merrill, and the Chairman. 



February 7, 1887. 



Kegular Business Meeting. 



The President, Dr. J. S. Newberry, in the chair. 



Sixteen persons present. 



The Eeport of the Council recommended the acceptance of 

 the resignation of Mr. John Townshend, which was adopted. 



Mr. a. p. Bjerregaard read a paper : 



keport upon the pink dolomite recently obtained near 

 morrisania, with analysis. 



Discussion. 



Prof. D. S. Martin thought that the mineral had some of 

 the characteristics of calcite, but should be regarded as a variety 

 of dolomite, the latter name properly being generic. 



Dr. a. a. Julien said that there had been too much reliance 

 upon chemical analysis alone ; a microscopic examination of 

 these dolomitic limestones shows a heterogeneous condition, 

 grains of calcite being mingled iu the mass. He thought that 

 the mineral might be a mingled calcite and dolomite. 



Mr. Bjerregaard said he had obtained little insoluble matter 

 in dilute acid, less than five per cent. 



Dr. Britton suggested that the color might be due to 

 manganese. 



The President spoke of the characters of true dolomite, and 



