1881.] 



Presents. 



249 



Classifying the sources of light used by Cornu, we get the following 

 approximate relative velocities : — 



Source of light . 



Xo. of 

 observations. 



Approximate relative 

 velocity. 





20 



298,776 kilos. 



Sun near horizon 



77 



300,242 „ 



Lime light 



449 



300,290 „ 



All these results seem to support the view that the more refrangible 

 the source of light, the greater is the velocity. But the evidence of 

 the present observations, indicating an excess of velocity for blue over 

 red light, seeming to exceed 1 per cent, of the whole, must rest upon 

 the merit of the present observations themselves. 



Presents, May 5, 1881. 



Transactions. 



Edinburgh:— Royal Society. Transactions. Vol. XXIX. Part 2. 



4to. Edinburgh 1880. ' Proceedings. Vol. X. No. 105. 8vo. 



Edinburgh 1880. The Society. 



Graz : — Naturwissenschaftlicher Verein fur Steiermark. Mittheil- 



ungen. Jahrg. 1880. 8vo. Graz 1881. The Association. 



Jena : — Medicinisch-naturwissenschaftliche Gesellschaft. Jenaische 



Zeitschrift. Bd. XIV. Supplement- Heft I. 8vo. Jena 1881. 



The Society. 



London: — Anthropological Institute. Journal. Vol. X. No. 2. 8vo. 

 London 1880. The Institute. 



Entomological Society. Transactions. 1881. Parti. 8vo. London. 



The Society. 



Institution of Civil Engineers. Minutes of Proceedings. Vol. 

 LXIII. 8vo. London 1881. Private Press, Nos. 1-12. 



The Institution. 



Meteorological Society. Quarterly Journal. Vol. VII. No. 37. 



List of Fellows. Jan. 1881. President's Address. 8vo. London 



1881. The Society. 



Royal Astronomical Society. Monthly Notices. Vol. XLI. No. 5. 



8vo. London 1881. The Society. 



Statistical Society. Journal. Vol. XLIV. Part 1. 8vo. London 



1881. The Society. 



Lyon :— Societe de Geographic Bulletin. Tome III. No. 19. 8vo. 



Lyon 1880. The Societv. 



s 2 



