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DIARY OF SOCIETIES. 



WEDNESDAY, March rr*. 

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THURSDAY, March 27. 

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CONTENTS. page 



Colour Vision 53 



A Medieval Physician. By Sir T. Clifford Allbutt, 



K.C.B., F.R.S 54 



The Structure and Biology of the Bacteria. Bv Prof. 



R. T. Hewlett 55 



Our Bookshelf 56 



Letters to the Editor:— 



TheRadio-Elementsandthe Periodic Law. — Frederick 



Soddy, F.R.S. 57 



An Unknown Assyrian Antelope. (Illustrated.) — -*■ 



R. Lydekker, F.R.S 5S 



Cavities in Stones. — E. VV. Swanton 59 



An Experiment for Showing Lines of Force in an 



Electrostatic Field. — R. F. D'Arcy 59 



Units of Pressure in Vacuum Work. — Dr. P. E. Shaw 50 



New Microscope Eyepieces. (Illustrated.) ... . 50, 



Standards and Tests for Sewage and Sewage Efflu- p([ 



ents. By E. A 61 



Birthmarks as a Test of Race • .... 62 



Colonel J. S. Billings, M.D. By Sir Lauder Brunton, 



Bart., F.R.S 62 



Notes 62 



Our Astronomical Column : — 



The 100-in. Reflector at Mount Wilson ... .... 67 



Solar Radiation During the Eclipse of April 17, 1912 . 67 



Bantu Star Names 67 



The Explosion of Worlds 67 



The Detroit Observatory 67 



The Institution of Naval Architects 67 



Colloids and their Viscosity . . . . 69 



Atmospheric Humidity and Temperature 69 



Recent Advances in Scientific Steel Metallurgy. 



(Illustrated.) By Prof. J. O. Arnold, F.R.S 70 



University and Educational Intelligence 72 



Societies and Academies 73 



Books Received 77 



Diary of Societies 7S 



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