628 
Wisconsin Academy of Sciences , Arts , and Letters. 
4. A new geometrical and analytical solution for determining the 
principal axes at any point of a rigid body. Charles S. Slichter. 
5. An elementary explanation of the probability curve. Charles S. 
Slichter. 
Reading of memorial sketches of the following deceased members: 
Harlow S. Orton, John G. Meaehem, Sr., Christian Preusser, Alice 
Aikens Bremer, Wayland S. Axtell, James C. Foye. 
Evening Session. —Academy banquet, complimentary to visiting mem¬ 
bers, followed by the address of the retiring president, Professor C. 
Dwight Marsh, cf Ripon College, 8:00 o’clock. “The Plankton of Fresh 
Water Lakes. 
Friday, December 29.—Reports of officers and other general business* 
Reading of papers. 
6. The ice ramparts formed along the shores of lakes Mendota and 
Monona during the winter of 1898-99. Ernest R. Buckley. 
7. The principles controlling the deposition of ores. Charles R. Van 
Rise. 
8. The nepheline syenite of the Wausau district. Samuel Weidman. 
9. The graphite deposits of central Wisconsin (preliminary note). 
Garry E. Culver. 
10. Chlorine in natural waters—its accurate determination and sig¬ 
nificance. Erastus G. Smith. 
11. The action of light on certain nitroso compounds. Oswald 
Schreiner. 
12. The sour taste of acid salts and their electrolytic dissociation. 
Louis Kohlenberg. 
13. The historical development of chemical symbols from the times 
of alchemy to the present. (Illustrated by lantern slides.) Oswald 
Schreiner. 
Saturday , December 30. —Election of officers and other general busi¬ 
ness. 
Reading of papers. 
14. The absorption of the sun’s energy by water. Edward A. Birge. 
15. Some of the undeveloped natural resources of Wisconsin: clays, 
road materials, and marls. Ernest R. Buckley. 
16. Account of some work done on the state survey. Dexter P. Nich¬ 
olson. 
17. The work of the Wisconsin Geological and Natural History Sur¬ 
vey. Edward A. Birge. 
18. On the changes of length of substances in an alternating magnetic 
field. William M. Jolliffe. (By title.) 
