ASTRONOMY. 3 



and of the Uranometria JVova, and of a zone examined by 

 himself at Milan from to -f-6 (3), and deduces the relative 

 distances of (1) the lucid stars; (2) the Durchmusterung 

 stars of 7.5, 8.0, and 9.5 magnitude ; (3) the stars of the Mil- 

 an zone ; and (4) those of HerschePs sweeps. This paper is 

 an abstract of a longer memoir published by the Milan Ob- 

 servatory. The principal conclusion of M. Celoria is as to 

 the existence of two rings which together make up the 

 Milky Way. The two absolute maxima of star-density are 

 in 6 h 50 m and 19 h 20 m R. A., and in the first region there is a 

 maximum of lucid stars. If it is admitted, as has been shown 

 by Gylden, that the different brightness of stars is in general 

 a function of their different distance, the conclusion follows 

 that towards 6 h R. A. the stars nearest ns are accumulated, 

 and that towards 19 h the stars farthest aw T ay are situated. 

 In the curves of star-density two maxima are shown in the 

 Milky Way, the first being smaller than the second; and it 

 follows that the branch of the Milky Way which comes first 

 to the meridian contains the stars nearest us. "The Milky 

 Way is thus formed of two rings whose planes are inclined 

 about 20 to each other, which cross each other; and the sun 

 is situated a little outside of their planes." Data for a re- 

 view of this kind have been collected from the star-maps of 

 Dr. C. H. F. Peters, of Clinton, by Professor Holden, of Wash- 

 ington, who has counted the number of stars per square de- 

 gree in all of Dr. Peters's star-maps, and in many of Chacor- 

 nac's charts, which have been completed by Dr. Peters by 

 filling in the small stars. In this way statistics of the dis- 

 tribution of stars of the first fourteen magnitudes over the 

 ecliptic regions have been collected. 



The Monthly Notices, R. A. S., for January, 18*78, contains 

 the following papers : Serlor Ventoza, of Madrid, has a note 

 on the real motion of the stars in space, which is an abstract 

 of a larger work to appear shortly. Mr. S. Waters, to whom 

 we owe several charts of the same kind, has given a chart of 

 the southern sky, on which the results of Sir John HerscheFs 

 star-gauges are plotted, and it serves to give a rough idea 

 of the distribution of the southern stars. 



Professor Winnecke, of Strasburof, brings evidence to show 

 that the nebula II ii. 278 (G. C. 551) has x>eriodicalhj va- 

 ried. From 1785-1827 it was p B; 1856-65 it was v F 



