94 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
MICROSCOPY. 
The Reaction of the Eye to Light. — Prentice Reeves (Research 
Laboratory, Eastman Kodak Co., N.Y.), ( Transactions of the Optical 
Society , 22, No. 1, 1920-21). 
Classification and Nomenclature of Optical Glass. — George W. 
Morey ( Journal of the Optical Society of America , July, 1920, 4 , 205- 
12 ). 
A Note on the Annealing of Optical Glass. — L. H. Adams and 
G. D. Williamson (< Journal of the Optical Society of America , July, 
1920, 4 , 213-23). 
Optical Properties of Anthophyllite. — N. L. Bowen (. Journal of 
the Washington Academy of Sciences, 10, No. 14, August 19, 1920). 
Dispersion in Optical Glasses. — F. E. Wright ( Journal of the 
Optical Society of America, May and July, 1920, 4 , 148-59, 195-204). 
Certain Relations between Chemical Composition and Refrac- 
tivity in Optical Glasses. — F. E. Wright ( Journal of the American 
Ceramic Society, 3, No. 10, October, 1920). 
Optical Glass and its Future as an American Industry. — 
Arthur L. Day, Ph.D., Sc.D. ( Journal of the Franklin Institute , 
October, 1920). 
The Unaided Eye. Part III. — James Weir French, B.Sc. 
(. Transactions of the Optical Society, 21 , No. 4, 1919-20). 
The Rock-Crystal of Brazil. — Robert R. Walls, M.A. B.Sc. 
(. Transactions of the Optical Society, 21, No. 4, 1919-20). 
METALLOGRAPHY. 
Constitution of Tungsten and Molybdenum Steels. — A. M. 
Portevin ( Iron and Steel Inst . Meeting , September, 1921). Extremely 
slow cooling is shown to effect in the disappearance of obviously hard 
states, and the structures generally supposed to be in equilibrium are 
then superseded by others characteristic of a still more advanced con- 
dition of stability. In Tungsten steels, the structure consists of a 
tungstitic ferrite, a tungsten carbide, a tungstitic troostite, and a new 
constituent — complex ferrite -f Fe 2 W. There are, however, only three 
phases — a solid solution, a tungsten carbide, and the compound Fe 2 W. 
A more highly carburized, though analogous constituent, is found in 
the case of Molybdenum steels. F. I. G R. 
