182 ASTRONOMY FOR 1889, 1890. 



Variable stars. 



Chandler (8. C.) The period of U Coroua-. Astrou. Jour., 9 : 97-9. 



. The variable Y Cygni. Astron. Jour., 9: 92-3. 



. Light- variations of U Cephei. Astron. Jour., 9: 49-53. 



. General relations of variable star phenomena. Astron. Jour., 9: l-f). 



. Contributions to the knowledge of the inequalities in the periods of the' 



variable stars. Astron. Jour., B: 161-6, 172-5. 

 [Pickering (E. C.)] Index to observatious of variable stars. Ann. Harv. 



Coll. Obsry., 18: 215-57. (v. 18, no. 8.) ^iso, Reprint. 

 SCHONFELD (E.) Ephenieriden veriiuderlicher Sterne fiir 1890. Vrtljschr. d. 



astron. Gesellsch., 24: 220-34. 

 Yendell (P. S.) Corrigendum to the elements of X Cygni. Astrou. Jour., 9: 8, 



Venus. 



ScHAPARELLi. Transl. by Tesby Lee. L'A8tron.,9: 285, 325, 411. Aug. and Sept. 



Yale Observatory. 



Transactions ... v. 1, pt. 2. Researches with the heliometer. Determination 

 of the orbit of Titan and the mass of Saturn, by A. Hall, jr. [37] p. 4to. 

 New Haven, 1889. 



