124 CARNEGIE INSTITUTION OF WASHINGTON. 



plants. Aside from the Marattiaceous structure of the synaugia, 

 the most important single determination made is that the strobili of 

 some of the Bennettiteae were functionally bisporangiate or bisexual, 

 a condition foreshadowed by Tumboa as having earlier existed among 

 the gymnosperms, but never before demonstrated in any member 

 of the group. These features bring the gymnosperms into close 

 apposition to the angiosperms, and strongly suggest a derivation of 

 both series of seed-bearing plants from a filicinian ancestry. 



PHYSICS. 



S. J. Barnett, Stanford University, Cal. Grant No. 149. For 

 research on the electric displace me7it induced in a certaifi dielectric 

 by motion in a magnetic field. $250. 



None of the experimental work planned by Professor Barnett has 

 yet been undertaken, as the necessary apparatus is still in process of 

 construction. 



William Campbell, Columbia University, New York, N. Y. Grant 



No. 179. For research on the heat treatmeyit of S077ie high-carbon 



steels. $1,500. 



Abstract of Report. — A series of high-carbon steels were heated to 



temperatures varying from 650° to 1,200° C. and slowly cooled. 



Their mechanical properties have been worked out, their electrical 



conductivity has been measured, and a preliminary examination of 



their microstructure made. 



The work will be continued by a detailed examination of their 

 microstructure. This will be followed by a series of experiments on 

 quenching and tempering, and the structure of the hardened steels 

 will be worked out, in connection with their transformation points. 



H. S. Carhart, University of Michigan, Ann Arbor, Mich. Grant No. 

 151. Por preparatioyi of viaterial for standard cells, etc. $500. 



Abstract of Report. — The problem to be solved is the determina- 

 tion in absolute measure of the electromotive force of Clark & 

 Weston standard cells, both of which are used as standards of 

 electromotive force in all the civilized countries of the world. 



An uncertainty of about one part in 1,000 exists in the value of 

 the electromotive force of these cells. The legal value for the 

 Clark cell in the United States is 1.434 international volts at 15° C, 

 but measurements made by Professor Carhart and Dr. Guthe (now 

 of the Bureau of Standards) in 1899, as well as those made since 

 by indirect methods in other parts of the world, show that the true 



