July 14, 1916] 



SCIENCE 



67 



THE IOWA ACADEMY OF SCIENCE 



The Iowa Academy of Science held its thirtieth 

 annual session with Drake University, Des Moines, 

 April 28 and 29, 1916. In the number of papers 

 presented this meeting exceeded any previous ses- 

 sion, a fact which speaks well for the scientific ac- 

 tivity of the students and investigators of the 

 state. The academy followed the plan instituted 

 last year of having most of the papers presented 

 before sectional meetings, of which there were 

 three — 1, Chemistry; 2, Physics; and 3, Botany, 

 Geology and Zoology. 



In the evening of the twenty-eighth Dr. Louis 

 Kahlenberg of the University of "Wisconsin gave 

 the annual address before the Academy on "Some 

 Eesults from the Experimental Study of Osmosis. ' ' 



The Iowa and Ames sections of the American 

 Chemical Society met with the Academy and an 

 Iowa section of the Mathematical Association of 

 America was organized during the meetings. 



The following were the officers elected to serve 

 during the coming year. 



President: G. W. Stewart, State University. 



First Vice-president: L. S. Boss, Drake Univer- 

 sity. 



Second Vice-president : Miss Alison E. Aitchison, 

 State Teachers College. 



Secretary: James H. Lees, Iowa Geological Sur- 

 vey. 



Treasurer: A. O. Thomas, State University. 



PROGRAM 



Abstracts are by the authors 

 Barium in Tobacco and Other Plants: Nicholas 



Knight. 



A number of samples of tobacco were examined 

 and a small quantity of barium found in each one. 

 The samples were obtained from Sumatra, Cuba 

 and from various sections of the United States. 

 Thirteen samples of leaves of common trees were 

 also examined, and a sample of the soil in which 

 they grew. 



Pure Sodium Chloride: Nicholas Knight. 



Samples of common salt were made by four dif- 

 ferent methods, and small amounts of potassium 

 chloride were found in each sample. Similar re- 

 sults were obtained from three samples of ' ' C.-P. ' ' 

 sodium chloride. 



Some Rock Analyses: Nicholas Knight. 



An Improved Method of Determining Solubility: 

 W. S. Hendrixson. 



Acid Potassium and Sodium Phthalates as Stand- 

 ards in Acidimetry and Alkalimetry, II.: "W. S. 

 Hendrixson. 



Some Auxoamylases : E. W. Eockwood. 



Electromotive Forces and Electrode Potentials in 

 Pure and Mixed Solvents, II.: P. S. Mortimore 

 and J. N. Pearce. 



The Behavior of Solutions at the Critical Tempera- 

 ture, a Preliminary Report: Perry A. Bond. 



A Comparison of Barbituric Acid, Thiobarbituric 

 Acid and Malonylguanidine as Quantitative Pre- 

 cipitants for Furfural: A. W. Dox and G. P. 

 Plaisance. 



An Accurate Aeration Method for Determining 

 Alcohol in Fermentation Mixtures: A. W. Dox 

 and A. B. Lamb. 



Relative Influence of Bacteria and Enzymes on 

 Silage Fermentation, Preliminary Report: A. B. 

 Lamb. 



Estimation of Calcium in Ash of Forage Plants and 

 Animal Carcasses: S. B. Kuzirian. 



The Pleasant Ridge Group of Effigy Mounds: 



Ellison Orr. 



These mounds are included in the proposed 

 Mississippi Valley National Park. This park will 

 include a strip of land along the bluffs from a 

 point about six miles south of McGregor, Iowa, to 

 the mouth of Yellow Biver, about three miles north 

 of McGregor. This group of mounds lies on a 

 very high point of the bluff about half way be- 

 tween McGregor and the mouth of Yellow Biver, 

 and is comprised of some eight or nine animal 

 mounds and three bird mounds, all in a good state 

 of preservation. 



An Old Roman Coin in South Dakota: David P£. 



Boot. 

 Contributions to the Geology of Southwestern 



Iowa: George L. Smith. 

 A Note on Fulgurites from Sparta, Wisconsin: W. 



D. Shipton. 

 A New Stratigraphic Horizon in the Cambrian 



System of Wisconsin: W. D. Shipton. 

 Records of Oscillations in Lake Level, and Records 



of Lake Temperature and Meteorology Secured 



at the Macbride Lakeside Laboratory, Lake Oko- 



loji, Iowa, July, 1915: John L. Tilton. 



Tidal effects were almost zero, barometric effects 

 too small to be detected without magnification, and 

 intake and outflow about equal. "Wind effects were 

 noticeable and quickly compensated by movement 

 in the lake. The wind directed the circulation in 

 the lake. The division of the lake water into 



