PAGE 



Ancient Pipes. Andrew J. Bigney 211 



Polarization of Cadmium Cells. B}' R. R. Ramsey 213 



The Effect of Pressure on a Cadmium Cell. By R. R. Ramsey 215 



Notes on the Calibration and Use of the Ballistic Galvanometer. Bj^ C. M. 



Smith 221 



Qualitative Detection and Separation of Potassium and Sodium. F. C. 



Mathers and I. E. Lee 227 



An Apparatus for the Study of the Radiation from Covered and Uncovered 



Steam Pipes. By O. W. Silvey and G. E. Grantham 229 



Ash and Calorimeter Tests of Coal Purchased by Indiana University. By 



Frank C. Mathers and Ira E. Lee 237 



Recovery of Silver from Silver Chloride Residues. By Frank C. Mathers. 241 



A New Gas Generator. By Raymond Bellamy 243 



Some Abnormal Plants. By Rajanond Bellamy 245 



A Modified Method totr he Determination of Lead Peroxide in Red Lead. 



By A. R. Nees and O. W. Brown 247 



A Simple Laboratory Method of Measuring Vapor Tension. By A. E. 



Caswell 251 



A Theorem on Addition Formulae. By Leslie MacDill 255 



Note on Multiply Perfect Numbers, Including a Table of 204 New Ones 



and the 46 Others Previously Published. By R. D. Carmichael and 



T. E. Mason 257 



Concerning Spheric Geometry, by David A. Rothrock 271 



On the Representations of a Number as the Sum of Consecutive Integers. 



By T. E. Mason 273 



Application of the Cauchy Parameter Method to the Solution of Different 



Equations. By T. E. Mason 275 



Some Variations in Plants. By F. M. Andrews 279 



Report of the Work in Corn Pollination, III. M. L. Fisher 283 



New and Notable Members of the Indiana Flora. E. J. Grimes 285 



A Monograph of the Common Indiana Species of Hypoxylon. Charles 



E. Owens 291 



The Improvement of Medicinal Plants. F. A. Miller 309 



Nutrients in Green Shoots of Trees. By E. J. Retry 321 



The New York Apple Tree Canker. By Lex R. Hesler 325 



Value of Fertilizing Constituents of Weeds of Indiana. Analysis of Iron- 

 weeds. By Frank Mathers and Miss Gail M. Stapp 341 



