Further Note on the Spectrum of Silicium. 403 



f Sir Michael Foster, K.C.B., D.C.L., LL.D. 

 Secretaries. < .rrmi -A- T A 



I Professor Arthur William Rucker, M.A., D.Sc. 



Foreign Secretary. Thomas Edward Thorpe, C.B., Sc.D. 



Other Members of the Council. Professor Henry Edward Armstrong, 

 LL.D. ; Charles Vernon Boys ; Horace T. Brown, LL.D. ; William Henry 

 Mahoney Christie, C.B. ; Professor Edwin Bailey Elliott, M.A. ; Hans 

 Friedrich Gadow, Ph.D. ; Professor William Mitchinson Hicks, M.A. ; 

 Lord Lister, F.R.C.S. ; Prof essor William Carmichael Mclntosh, F.L.S.; 

 Ludwig Mond, Ph.D. ; Professor Arnold William Eeinold, M.A. ; Pro- 

 fessor J. Emerson Reynolds, Sc.D. ; Robert Henry Scott, Sc.D. ; Pro- 

 fessor Charles Scott Sherrington, M.D. ; J. J. H. Teall, M.A. ; Sir John 

 Wolfe Barry, K.C.B. 



The following Papers were read : 



I. " Further Note on the Spectrum of Silicium." By Sir J. NORMAN 

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



II. " On Solar Changes of Temperature and Variations in Rainfall in 

 the Region surrounding the Indian Ocean." By Sir J. NORMAN 

 LOCKYER, K.C.B., F.R.S., and Dr. W. J. S. LOCKYER. 



III. u On the Restoration of Co-ordinated Movements after Nerve- 

 crossing, with Interchange of Function of the Cerebral Cortical 

 Centres." By Dr. ROBERT KENNEDY. Communicated by 

 Professor McKENDRiCK, F.R.S. 



"Further Note on the Spectrum of Silicium." By Sir NORMAN 

 LOCKYEK, K.C.B., F.R.S. Received October 26, Read Novem- 

 ber 22, 1900. 



In a previous note* I gave an account of some observations on the 

 spectrum of silicium, and showed the relation which exists between the 

 various groups of silicium lines and certain lines prominent in the 

 spectra of some of the hottest stars. 



Further photographs have recently been obtained (with a 3-inch 

 Cooke spectrograph) of the spectrum of silicium bromide in a capillary 

 vacuum tube, and of the spark spectrum between two poles of metallic 

 silicium which were kindly sent to me by Sir William Crookes. In 

 each case the large Spottiswoode coil and plate condenser were used. 

 The spectra extend from about A 3850 to D, and occupy a length of 

 about 7 inches between those limits. Although all the silicium lines are 



* ' Hoy. Soo. Fror.,' vol. 65, p. 449. 



2 G 2 



