5 2 ASTRONOMY 



52373 Hale, Q. E., and Fox, P. Eotation period of the sun. 



Wash. 1908. 



52373 Hubrecht, J. B. The Solar rotation in June, 1911, from 

 spectroscopic observations. Camb. 1915. 



^52374 Birkeland, K. Eecherches sur les taches du soleil. 



Christiania 1899. 

 52374 Peters, C. H. F. Heliographic positions of sun spots. 



Wash. 1907. 

 52376 Lockyer, Sir J. N. Contributions to solar physics. 



Lond. 1874. 



/'5 2 377 McClean, F. Comparative spectra of the high sun and 

 low sun. Lond. [1890]. 



/'5 2 377 Comparative spectra of the sun and the metals. 



Lond. [1891]. 



52378 Langley, S. P., and Abbot, C. G. The 1900 solar 

 eclipse expedition. Wash. 1904. 



52378 Naegamvala, K. D. Eeport on solaT eclipse of 1898. 



Bombay 1902. 



5238 STELLAR SYSTEM. 



5238 Hale, Q. E. The Study of stellar evolution. 



Chicago 1909. 



5238 See, T. J. J. Evolution of the stellar systems. 2 vols. 



Lynn, Mass. 1896-1900. 

 52381 Russell, H. N. Determinations of stellar parallax. 



Wash. 1911. 



52382 Parkhurst, J. A. Eesearches in stellar photometry. 



Wash. 1906. 



52382 Yntema, L. On the total amount of starlight. 



Groningen 1909. 



52383 Burnham, S. W. Measures of proper motion stars. 



Wash. 1913. 



52383 Campbell, W. W. Stellar motions. 



New Haven, Conn. 1913-> 



52383 Maanen, \. van. The Proper motions of 1418 stars. 



Utrecht 1911. 



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