Astronomy. 475 



Table V does not conform to the law deduced by Kapetyn of 

 connection between parallax and types of spectra, but the data 

 are hardly sufficient to disprove the law. 



The parallaxes grouped in order of magnitude appear as fol- 

 lows : 



Number of stars with negative parallax, —0*13" to — 0'00"__36 



small " +0-00 to +0'02 ..40 



considerable " +0*04 to +0'09 __49 



large " +0'10 to -+ 0"20 __38 



Of the last group the average magnitude is 5*8 and the average 

 parallax 0-163", corresponding to a distance of 20 light-years, 

 which is two-thirds that of the 9 first magnitude stars. The 

 average proper motion of the group is # 90", one and one-half 

 times that of the first magnitude stars. 



Two results of more popular interest may be stated as follows : 



Proper motion is a far more reliable guide than brightness in 

 estimating distance. 



There is probably not more than one star in the northern 

 heavens nearer to us than 61 Cygni. 



In the last group is found the noteworthy addition to our knowl- 

 edge of astronomy furnished by this work. All of its stars will 

 be subjects of study in the observatories of the world for many 

 years. w. b. 



2. Publications of the United States Naval Observatory r , 

 Superintendent, Rear- Admiral Asa Walker, U. S. N. Second 

 Series, 4to, Volume IV, in four Parts, Parts I to III. — Part I 

 contains Transit-Circle Observations of Sun, Moon, Planets and 

 Miscellaneous Stars, 1900-1903. Part II contains Transit Circle 

 Observation of Sun, Moon, Planets and Comets, 1866-1891. 

 Part III contains Transit Circle Observation of Standard and 

 Zodiacal Stars, 1901-1902. 



Part IV forms a separate volume and is largely devoted to a 

 discussion of observations made at the total solar eclipses of May 

 28, 1900, and May 17, 1901, with numerous illustrations. At the 

 former, stations were occupied on the central line at Barnesville 

 and Griffin, Georgia, and at Pinehurst, N. C. For the eclipse of 

 1901 an expedition was sent to Sumatra under the charge of Prof. 

 A. N". Skinner and several stations occupied at which successful 

 observations were made yielding important results, especially as 

 regards the form of the corona. This subject is illustrated by a 

 series of excellent plates. 



