

Some Structural Properties of Gypsum and of Rein- 

 forced Gypsum, W. A. Slater 157 



Wind Stresses in Steel Skeleton Construction, W. M. 

 Wilson 168 



Heat Transmission of Simple and Compound Walls, 

 with Special Reference to Building - Construction, 

 Arthur C. Willard 171 



The Determination of V and E/M for Cathode Rays 

 as a Laboratory Experiment in Physics, Chas. T. 

 Knipp 187 



The Reflecting Power of Alkali Metals in Contact with 

 Glass — As Determined by the Photo-Electric Cell, 

 Abstract, J. B. Nathanson 188 



On the Initial Conditions of the Corona Discharge, 

 Jacob Kunz 190 



A Wehnelt Cathode Ray Tube Magneto-Meter, L. A. 

 Welo 191 



Papers on Geology and Geography 



Graphical Method of Determining the Average In- 

 clination of a Land Surface from a Contour Map, 

 John L. Rich 195 



Present Condition of the Oil Industry, Fred H. Kay..200 



The Variety of Physiographic Material in a Few 

 Counties of Southern Illinois, Clarence Bonnell... .203 



The Present Status of the Dolomite Problem, Francis 

 M. Van Tuyl 208 



The Genesis of Sedimentary Rocks, an Undeveloped 

 Field in Geology, Abstract, Francis M. Van Tuyl. .209 



The Chloritic Material in the Ores of Southeastern 

 Missouri, Abstract, C. S. Ross 209 



Lateral Erosion in the Upper Illinois Valley, by the 

 Chicago Outlet, Abstract, Gilbert H. Cady 210 



The New Richmond Sandstone of Northern Illinois, 

 Abstract. Gilbert H. Cady 210 



The Stratigraphy of the Kinderhook Group in Western 

 Illinois and Missouri, Abstract, R. C. Moore 211 



Erosion Features of the Mesa Verde, W. H. Haas... .211 



