186 TRANSACTIONS OF THE [ApR. 3 



Journal, December 17, 1892, p. 581 ; the Scientific American, 

 December 31, 1892, p. 423 ; the School of Mines Quarterly, 

 January, 1893, p. 93, with two steel portraits, one taken in 1865 

 and one in 1887 ; the Bulletin of the Torrey Botanical Club, 

 March, 1893, with an artotype ; and the Bulletin of the Geo- 

 logical Societ}' of America, Proceedings of the Ottawa Meeting, 

 December, 1892, also with an artotype. A memorial, by Profes- 

 sor J. J. Stevenson, is to appear in the American Geologist for 

 July, 1893, with a revised chronological bibliography by J. F. 

 Kemp, 



April 3, 1893. 

 Regular Business Meeting. 



President Bolton in the chair, and twentj'-seven persons 

 present. 



section of astronomy and physics. 



A paper was read by Professor William Hallock entitled 

 "Investigations of the Temperature of the Earth's Crust." 

 This paper gave an account of temperature measures made at 

 Wheeling, W. Va., in a dry well 4,500 feet deep. These meas- 

 ures, when plotted, showed a small but distinct variation from 

 uniformity in the rate of increase of the earth's temperature. 

 The results have been described in Proc. Am, Assn., Vol. XL., 

 p. 257 ; and Am. Journ. Sci., March, 1892. 



Mr. Tatlock then read a note on the place of A Urs?e Minoris, 

 calling attention to the bearing upon the subject of Dr. Elkin's 

 recent heliometric triangulation of close polar stars. The 

 matter was further discussed by Professor Safford and Mr. 

 Jacoby. 



Professor S.\ffokd read a paper entitled, " The Construction 

 of a Catalogue of Standard Polar Stars." The paper dealt 

 with the various peculiar difficulties attending the observation 

 of close i^olar stars, as well as the complexity and great length 

 of the resulting computations. The author referred to his own 



