RECENT ADVANCES IN SCIENCE 13 



EvERSHED, J., Displacement of the Lines in the Solar Spectrum and Ein- 

 stein's Prediction, Observatory, 43, 153, 1920. 



St. John, C. E., Displacement of Solar Lines and the Einstein Effect, Obser- 

 vatory, 43, 158, 1920. 



Double Biliary and Variable Stars. 



WiRTZ, C, and Schreyer, W., Die Farben der Doppelsterne nach den 



Beobachtungen von Ercole Demboweki, Ast. Nach., 210, Nos. 5034-5, 



1920. 

 Voute, J., Doppelsternmessungen angestellt am Fadenmikrometer des 



io|-Zolligen Refractors von 1910 Aug. bis 1913 June, Leiden Obs. 



Annalen, 10, pt. ii, 1913- 

 Harper, W. E., v Geminorum, A Long-period Binary, Pxib. Dam. Obs. 



Ottawa, 4, No. 19, 1919- 

 CoMSTocK, G. C, 70 Ophiuchi and Neighbouring Stars, Ast. Journ., 32, 



No. 764, 1920. 

 Plaskett, J. S., Spectroscopic Orbits and Dimensions of the Eclipsing 



Variables, U Ophiuchi, RS Vulpeculae, TW Draconis, /oMfw. R.A.S.C., 



14, I, 1920. 

 VoGT, H., Zur Theorie der Algol veranderlichen, Veroff. der Grossh. Stern- 



warte Heidelberg, 7, No. 9, 191 9. 

 Turner, H. H., On the Suggested Decrease of Period of Stars in Phillips' 



Group II, with Particular Notes on R Hydras, etc., M.N., R.A.S., 80, 



273, 1920. 



Stellar Distributions and Motions. 



Wolf, M., Katalog von 1053 starken bewegten Fixsternen, Veroff. der Grossh. 



Sternwarte Heidelberg, 7, No. 10, 1919. 

 Porter, J. G., Catalogue of Proper Motion Stars, Pub. Cincinnati Obs., 



No. 18, pt. 4, 1918. 

 ZwiERS, J. H., Untersuchungen fiber die Deklinationen und Eigenbewe- 



gungen von 163 Sternen, Leiden Obs. Annalen, 10, pt. iii, 191 7. 

 Halm, J., Statistical Investigation of the Distribution of the Stars and 



their Luminosities, M.N., R.A.S., 80, 162, 1919. 

 Reinmuth, K., Photographische Positionsbestimmung von 356 Schultzschen 



Nebelflecken, Veroff. der Grossh. Sternwarte Heidelberg, 7, No. 6, 191 5. 



141 Photographische Nebelpositionen, ibid., 7, No. 8, 1916. 

 LuNDMARK, K., The Relations of the Globular Clusters and Spiral Nebulae 



to the Stellar System, Kungl. Svensk. Vetensk. Hand., 60, No. 8, 1919. 

 Pickering, E. C, and Kapteyn, J. C, Durchmusterung of Selected Areas 



between S = o and S =+ 90°, Harvard Annals, 101, 1918. 

 Schouten, W. J. A., The Distribution of the Absolute Magnitudes among the 



Stars in and about the Milky Way, Konink. Akad. van Wetens. te Am- 

 sterdam, 21, Nos. 6 and 7, 1918. 



Nebulae, Photometry, etc. 



Schoenberg, R., Researches on the Photometry of the Heavens: Pt. I, 

 On the Illumination of Planets, Pub. Astl. Obs. of Univ. Dorpat, 24, 

 pt. iii, 1917. 



Lundmark, K., and Lindblad, B., Photographic Effective Wave-length of 

 Nebulae and Clusters, Astroph. Journ., 50, 376, 1919. 



Shapley, H., Studies based on the Colours and Magnitudes of Stellar Clus- 

 ters, 15th Paper : A Photometric Analysis of the Globular System 

 Messier 68, Astroph. Journ., 51, 49, 1920. 



Hubble, E. P., Photographic Investigations of Faint Nebulae, Yerkes Obs. 

 Pubs., 4, pt. ii, 1920. 



