ASTRONOMY. 7 



copious notes referring to previous measures. For impor- 

 tant stars the entire history is given or rendered accessible, 

 a special treatment having been adopted for binaries. It is 

 to be printed as an Appendix to the Washington Astronom- 

 ical Observations for 1876, and will be eagerly looked for- 

 ward to by all to whom such a work is a daily need. 



The Observatory at Cincinnati lias begun its work, since 

 its removal to its new site, by researches in this field. The 

 former observations of Mitchell have been reduced and pub- 

 lished, and also a series of measures of double stars of south- 

 ern declination. It is announced by the director, Professor 

 Stone, that it is the plan of the Observatory to observe the 

 doubles lying in the zone between 15 and 35 S. The great 

 number of measures made by Otto v. Struve, at Pulkova, 

 have been reduced and printed, but no copy has yet reached 

 the United States. Recent measures of a large number of 

 Struve's doubles are, however, available in the work of Dune r, 

 of Lund. This includes 2679 observations made in the nine 

 years from 1867 to 1875. Measures of many of the doubles, 

 arranged in chronological order, accompanied by a tolerably 

 full discussion of the whole series of observations, from Her- 

 schel's to Duner's, are given. A table is added in which the 

 stars are arranged in classes according: to the arc throuo-h 

 which they have moved since the earliest observation. 



Class I. contains those stars which have moved through a 

 complete revolution, and comprises 8 stars. 



Class II., those stars which have moved through 180 of 

 their apparent orbit 8 stars. 



Class III., those which have moved through 90 8 stars. 



Class IV., those which have moved through 30 16 stars. 



Class V., those which have moved through 10 4S stars. 



Class VI., those which certainly have an orbital motion 

 59 stars, etc., etc. So that there are 147 stars in this list 

 which have been proved to be binary in character. 



The recent measures of Dembowski, Ferrari, Schiaparelli, 

 Wilson and Seabroke, Hall, ISTewcomb, Gledhill, and others 

 are noteworthy, as well as the theoretical researches of Do- 

 berck on binaries, but they are too numerous to be referred 

 to in detail. 



The work of Lord Lindsay ("Publications of the Dun-Echt 

 Observatory," vol. i.) is intended to supply the place of a g;cn- 



