CONTENTS. 



Chapters in Spectrum Analysis. I (continued). 



By W. Marshall Watts, D.Sc. 97 



On the Formation of Hair Pigment. 



By H. Onslow. 101 



Dust. By William Swaine. ... ... ... ... 103 



The Making of Gun-flints. 



By Wilfred Mark Webb. F.L.S. 106 



Solar Disturbances during February, 1915 



Notes (continued) : — 



Meteorology. By William Marriott. F.R. Met. Soc. 114 

 Microscopy. ... By J. E. Barnard. F.R.M.S. 115 



Photography By Edgar Senior. 116 



Physics. By J. H. Vincent. M.A.. D.Sc. A.R.C.Sc. 117 

 Radio-Activity. By Alexander Fleck, B.Sc. 118 



Zoology. 



By Professor J. Arthur Thomson. M.A.. LL.D. 119 



By Frank C. Dennett. Ill Number of Spores in a Myxomvcete. 

 Notes — By W. B. Grove. M.A. 120 



Astronomv. The Face of the Sky for May. 



By A. C. D. Crommelin. B.A.. D.Sc. F.R.A.S. 112 By A. C. D. Crommelm. B.A.. D.Sc, F.R.A.S. 121 



Botany. By Professor F. Cavers, D.Sc, F.L.S. 112 Pollards. ... ... ... ... ••• ■•• ••• 122 



Chemistry. Stonyhurst College Observatory. 



By C. Ainsworth Mitchell. B.A., F.I.C. 113 By Frank C. Dennett. 125 



Geography By A. Scott, M. A.. B.Sc. 113 Reviews 125 



Geology. By G. W. Tyrrell, A.R.C.Sc. F.G.S. 114 Notices 128 



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