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Diary of Societies. 



THURSDAV. OCTOBEB 7 

 HorAt .\EBONArTlcAi. SotiElT (at Royiil Society of Arts), at 5.30 — 



Maj.-G*iil. Sir F. H. Sykes: CiTil .\Tiation." 

 OHliD-STiDr SociETr (at Hoynl Snnitary Institute), at 6.— Dr. C. W. 



Simmins : Tlie Hnndwritinp of the Future. 



MOXDAr. October 11. 

 BiocREUioi Socirrr (nt King's Collog^l. 



WliDXKSDAY. OcTOBEB 13. 



Institution- of .\rTOMOHiLE Engineehs (nt Royal Swietv .>f \rt-i_ 



lit 8. — Sir Henry Fowler : Presidential Address. 



THfRSDW. October 14. 



IxsTiTUTlo.v OF ,\rTOiiOBir.E Knoineers (at 28 Victorii* .Strrtit), 



at 8. — Graduates Meetinjr. Mo<Mirs. Chatt^rton and Watson : 



Factors affectijijr Power Output. 



FRIDAY. October 15. 



Royal College of Suroeonji of RNfa-ANp. at .5.— Prof. A. Keith ; De- 

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RoTAl SoclETT or .\RTS ilndian Section), at 4 30— T. SI. Alns- 

 conpli : British Trade with India. 



SATIRDAT. October 16. 

 PHr.siOLOoiCAL SociETT (at Gny's Hospital). 



CONTENTS. PAGE 



A " Tour de Force" 137 



The Dioptrics of Huygens. ByJ. L. E. D 140 



Analysis of Foods, By C. S 141 



Adventitious Plants of Tweedside 142 



Meteorological Constants 142 



Our Bookshelf ... 143 



Letters to the Editor:— 



The Separation of the Isotopes of Mercury. — Prof. 



J. N. Bronsted and Dr. G. Hevesy 144 



The British Aswciation — Prof. W. M. Bayliss, 

 F.R.S.; Prof.L. N. G. Filon, F.R S.; Dr. John 

 W. Evans, F.R.S. ; Dr. Wm. Garnett ; Rev. 

 A. L. Cortie, S.J. ; Prof. Arthur R. Cushny, 



F.R.S ... 144 



Uses for Aircraft.— A. Mallock, F.R.S 147 



Minerals Hitherto Unknown in Derbyshire. — C. S. 



Garnett 148 



Wheat-biilb Disease.— Prof. James F. Gemmill . 148 

 The Iridescent Colours of Insects. I. {Illustrated.) 



Bv H. Onslow 149 



Ballistic Calculations. By D. R. Hartree 152 



Obituary 154 



Notes 155 



Our Astronomical Column : — 



Epheineris of Pallas 160 



Tempel's Periodic Comet 160 



Eclipse Observations at Monte Video .... 160 

 Fossils and Life. I. By F. A. Bather, M.A., D.Sc, 



F.R.S 161 



The Constitution of Cellulose 164 



Joseoh Black and Belfast. By Sir T. E. Thorpe, 



C.B., F.R.S 165 



The Sakura-jima Eruption of 1914. By CD. . . 165 



University and Educational Intelligence 166 



Societies and Academies 166 



Books Received 167 



Diary of Societies 168 



