RECORDS. 343 



motive were 11.48 inch-pounds, per pound of static load, con- 

 strained by a negative bending moment of 1.7 1 inch-pounds. 



On December 30 locomotive No. 2032, a ten-wheel type of 

 engine, with closer wheel spacing, weighing 283,900 pounds, 

 drawing the "Southwestern Limited" of ten cars weighing 

 910,000 pounds, at a speed of 40 miles per hour, at the same 

 place as the preceding tests, the positive bending moment for 

 the engine was 10.80 inch-pounds per pound of static load, for 

 one rail, constrained by a negative bending moment of 2. 1 8 inch- 

 pounds — a more favorable result than for the eight-wheel type. 



For the entire locomotive, the positive bending moment — 

 for normal tender wheels — was 9.82 inch-pounds, for one rail, 

 constrained by a negative bending moment of 1.90 inch-pounds, 

 indicating a more favorable loading of the foundation. The 

 bending moments of different types of locomotives on the same 

 superstructure are a measure of the relative efficiency of the dis- 

 tribution of their loads to the foundation ; while with the same 

 type of engine the relative efficiency of the construction of the 

 superstructure of the permanent way can be measured. These 

 are first bending moments measured in rails under moving loco- 

 motives and cars. 



Dr. H. G. Piffard exhibited an electrometer specially designed 

 for use in measuring radioactivity, and showed the action of the 

 instrument by lantern projection. 



C. C. Trowbridge, 



Sca^ctmy. 

 SECTION OF BIOLOGY. 



May 9, 1904. 



Section met at 8:15 P. M., Vice-President Underwood pre- 

 siding. The minutes of the last meeting of Section were read 

 and approved. 



The following program was then offered : 



E. W. Berry, The Cycadofilicales and the Origin of the 

 Seed Plants. 



D. T. MacDougal, Morphogenic Changes Caused by the 

 Transposition of Aquatic and Terrestrial Plants. 



Alter the stated papers were presented Professor Dean exhib- 



