November 21st, 1887. 



President Nipher in the chair ; thirteen members present. 



Mr. H. A. Wheeler read a paper by W. J. McGee, U. S. Ge- 

 ologist, entitled, "Notes on the Geology of Macon County, Mo.'"" 

 Referred to the Committee on Publication. 



Prof. Nipher exhibited a steam-pipe, six inches in diameter^ 

 which had been capped with a plain cast-iron head. The head 

 of the pipe (9 lbs) had been blown off by a ball from a Winches- 

 ter rifle. He explained that this had been done by standing the 

 pipe on its closed end and filling it with water. The ball had been 

 fired down vertically upon the water. The floor upon which the- 

 pipe stood had yielded, and the head of the pipe had been forced 

 down by the water pressure with such quickness that the pipe 

 could not follow. The head of the pipe had therefore been pushed' 

 off. To do this required a force of between 135,000 and 150,000. 

 lbs., or about 70 tons. The ball was a 38 calibre ball and the 

 charge of powder was 40 grains. The pipe was 5 ft. long, and 

 exclusive of the head weighed 96 lbs. The ball was greatly flat- 

 tened by the water, but did not batter on the bottom. 



Mr. J. A. Seddon exhibited a chart showing the results of a 

 series of precise levellings made by the Missouri River Commis- 

 sion between St. Louis and St. Charles. 



December ^t/i, 1887. 



President Nipher in the chair ; six members present. 



Mr. W. G Eliot, Jr., presented a paper on some measurements 

 of the trimorphic flowers of Oxa/is Suksdorfii, Trelease, in which 

 the heterogony of the species was clearly shown ; and the mutual 

 relation of stamens and pistils in the three forms of flowers were 

 graphically represented in a series of curves obtained by plotting; 

 the measurements. 



In commenting upon the paper, Mr. Trelease called attention 

 to the dymorphism of Oxalis violacea, as it occurs through the 

 Upper Mississippi Valley, from the suppression of the mid-styled 

 form, and by the means of a similar series of curves contrasted 

 this species with Oxalis Snksdorfii, calling especial attention to 

 the unexplained fact that in both species the mid-length stamens 



