(J24 SUMMARY OF CUKKENT RESEARCHES. 



Microscopic Effects of Stress on Platinum.* — Messrs. T. Andrews 

 find C. R. Andrews prepared an ingot of pure platinum, carefully ma- 

 chined into a cube 0*30 in. square. This was microscopically polished 

 and subjected to a compression stress of 12 '82 tons per square inch, 

 thereby reducing its height by 10 p.c. of the original dimension. Tho 

 result was to produce a great number of " slip-bands," roughly inclined 

 at an angle of 45° to the line of the compression force on the crystal 

 sectional facets. The experiment is confirmatory of the observations 

 of Ewing and others, that stress alone, without etching, sometimes 

 renders manifest the lines of inter-crystalline junction of the large or 

 primary crystal grains of a stressed metal, providing that the stress 

 is of sufficient intensity. 



Eichards, B. E. — System of Recording Cultures of Bacteria genealogically for 

 Laboratory Purposes. 



[This system furnishes a convenient means of recording all data relating to 

 the study of individual laboratory cultures of bacteria.] 



Joum. Applied Microscopy, 1902, pp. 1877-83. 

 Starrow, F. W., E.N — Principles of Simple Photography. 



[A manual embodying the ruling principles of. elementary photography.] 



London, Hazell, Watson & Viney, 1902, 130 pp., 

 with illustrations by the author. 



* Tree. Eoy. Sec, lsx. No. 4C2 (1902) pp. 250-2 (3 figs.). 



