PHYSICS — BURGESS, CARHART. 213 



carbon, it being the desire to investigate alloys having a lower content of 

 carbon than those with which other investigators have worked. A large 

 number of alloys of iron-copper, iron-nickel, and iron-tungsten have been 

 made, as well as a number of samples of each of the following combinations : 

 Iron-chromium-silicon, iron-chromium-nickel, iron-molybdenum, iron-molyb- 

 denum-vanadium, iron-chromium, iron-tungsten-vanadium. 



A number of interesting observations have been made in the testing of 

 these alloys, but reports will not be made until the chemical analyses can 

 be secured. In most cases the composition of the alloys is known only by 

 knowing the proportions of materials put into the charge, and, while some 

 checked analyses have been made, a large amount of analytical work is now 

 necessary before the composition of the alloys can be definitely stated, and, 

 when this w'ork is completed, a large amount of material will undoubtedly be 

 available for publication. 



Messrs. Bechlem and Wadsworth have conducted a thesis investigation 

 upon high-speed tool-steels made from our electrolytic iron, and they have 

 demonstrated the suitability of the material for this purpose. Prof. A. H. 

 Taylor and Mr. E. M. Terry, of the Physics Department, are conducting 

 extensive tests on the magnetic properties of the electrolytic iron and alloys, 

 and their work is to be continued through this year. 



It is the plan to complete during the coming year some of the various 

 lines of study mentioned and to study somewhat exhaustively one or more of 

 the alloys above named. 



Carhart, Henry S., University of Michigan, Ann Arbor, Michigan. Grant 

 No. 151. Determination of the electromotive force of Clark and Weston 

 cells, and of the electrochemical equivalent of silver. (For previous 

 reports see Year Book No. 3, pp. 124-126; Year Book No. 4, p. 250, and 

 Year Book No. 5, pp. 226, 227.) $500. 



The work with the absolute electrodynamometer for the measurement of 

 the electromotive force of the Weston cell has been carried forward during 

 the past year, but no results are to be reported different from those of the 

 preceding year. 



Progress has been made in another direction, namely, in the investigation 

 of the silver coulometer, and in the redetermination of the electrochemical 

 equivalent of silver. Preliminary work in this subject was in progress for a 

 year before any attempt was made to determine the silver equivalent. It 

 involved the very important effort to find if possible a salt of silver superior 

 to the nitrate as an electrolyte. This inquiry was stimulated by the theory 

 of Prof. T. W. Richards, which has been widely accepted, that with silver 

 nitrate as the electrolyte a heavy anodic liquid is formed, which increases the 

 deposit of silver if it is allowed to reach the cathode. 



