536 SCIENCE PROGRESS 



ViNTER Hansen, Julie M., GenSherte Tafeln des Planeten 24 Themis, Ast. 

 Nach., 212, Nos. 5073-4. 1920. 



BoDA, K., Untersuchungen iiber die allgemeinen Jupiter-Storungen des 

 Planeten 170 Maria, Ast. Nach., 212, Nos. 5080-81, 1920. 



Valentiner, W,, Bearbeitung und Katalogisierung der am Repsoldchen 

 Meridiankreis des Heidelberger Astr. Instituts in den Jahren 1902-1909 

 angestellten Beobachtungen der Gillschen Zodiakalsterne, Veroff. der 

 Grossh. Sternwarte zu Heidelberg, 5, pt. ii, 1917. 



OsTHOFF, H., Die Veranderlichkeit der Licht- und Farbe-Empfindungen, 

 Ast. Nach., 212, Nos. 5071-2, 1920. 



Ross, F. E., Photographic Photometry and the Purkinje Effect, Astroph. 

 Journ., 52, 86, 1920 ; Image Contraction and Distortion on Photographic 

 Plates, ibid., 52, 98, 1920 ; Photographic Sharpness and Resolving 

 Power, ibid., 52, 201, 1920. 



WiLSiNG, J., Messungen der Farben, der Helligkeiten und der Durchmesser 

 der Sterne mit anwendung der Planckschen Strahlungsgleichung, Potsdam 

 Obs. Pub., 24 No. 76, 1920. 



Hertzsprung. E., Photographische Messungen von Doppelsternen von 1914-0 

 bis I9i9"4, Potsdam Obs. Pub., 24, No. 75, 1920. 



Jackson, J., and Furner, H. H., The Hypothetical Parallaxes of 556 Visual 

 Double Stars, with a Determination of the Velocity and Direction of 

 the Solar Motion, M.N., R.A.S., 81, 2, 1920. 



Peter, B., Parallaxen Bestimmungen an dem Repsoldschen Heliometer der 

 Leipzigen Sternwarte (bearb. von H. Naumann), Abhand. der Math.-Phys. 

 Klasse der Sachs. Akad. der Wissenschaften, 38, No. i, 1920. 



Greenwich, Royal Observatory, Stellar Parallaxes determined at the 

 Royal Observatory, Greenwich, M.N., R.A.S., 81, 32, 1920. 



Biesbroeck, G. van, and Pettit, Hannah, S. Parallaxes of Fifty-two 

 Stars, Yerkes Obs. Pub., 4, pt. iii, 1920. 



ScHLESiNGER, F. (and Others), Photographic Determinations of the Paral- 

 lalex of Forty-nine Stars, Allegheny Obs. Pub., 4, No. 3, 1920 ; ditto 

 of Thirty Stars, ibid., 4, No. 4, 1920 ; Ditto of Twenty-five Stars, ibid., 

 4, No. 5. 1920 ; Ditto of Twenty-eight Stars, 5, No. i, 1920 ; Ditto 

 of Forty-nine Stars, ibid., 5, No. 3, 1920 ; Ditto of Forty-six Stars, 

 ibid., 5, No. 5, 1920. 



Hudson, C. J., Photographic Determinations of the Parallaxes of Thirty-one 

 Stars, Allegheny Obs. Pub., 4, No. 2, 1920 ; Irregularities in Refraction, 

 ibid., 6, No. I, 1920 ; The Effect of Atmospheric Dispersion on Photo- 

 graphs taken with the Thaw Telescope, ibid., 6, No. 2, 1920. 



Trumpler, R., Photographic Determinations of the Parallaxes of Twenty- 

 three Stars, Allegheny Obs. Pub., 5, No. 2, 1920. 



Henroteau, F., Photographic Determinations of the Parallaxes of Thirty- 

 four Stars, Allegheny Obs. Pub., 5, No. 4, 1920. 



Stratton, F. J. M., The Spectrum of Nova Geminorum II, Annals Solar 

 Physics Obs., 4, pt. i, 1920. 



Shane, CD., The Spectra of Certain Class N Stars, Lick Obs. Bull., 10, 

 No. 329, 1920. 



Evershed, J., On the Displacement of the Triplet Bands near X 3883 in the 

 Solar Spectrum, Kodaikanal Obs. Bull., No. 64, 1920. 



Meggers, W, F., Solar and Terrestrial Absorption in the Sun's Spectrum 

 from 6500 A to 9000 A, Allegheny Obs. Pub., 6, No. 3, 1920. 



Parask^vopoulous, J. S., The Perturbations of the Orbit of the Spectro- 

 scopic Binary, 13 Ceti, Astroph. Journ., 52, no, 1920. 



Dugan, R. S., a Photographic Study of V Cephei, Astroph. Journ., 52, no, 

 1920. 



Royds, J., Some Features of Ha Dark Markings on the Sun, Kodaikanal Obs. 

 Bull., No. 63, 1920. 



