188 ASTRONOMY. 



ZEAU. During a stay in Jamaica the author resolved to form a new 

 Urauometry, which should possess the advantage above all others hith- 

 erto pubhshed, that it was to be the work of a single individual, observ- 

 ing all the stars in both hemispheres visible to the naked eye within a 

 short space of time. He accordingly commenced working on January 

 28, 1875, and the work was finished on February 28, 187G. He had first 

 prepared maps, on which all the stars were i)lotted down without regard 

 to magnitude ; then every region was gone over two or three times, and 

 the magnitudes carefully estimated, the six usual classes being used, 

 but each class only divided into two halves. The atlas thus formed 

 consists of five plates, on which the stars, their letters, the names and 

 limits of the constellations (but not their figures), and the milky way 

 are depicted. The latter has been attended to with great care, the 

 deeper or paler hue of the light-green color rej) resenting greater or lesser 

 brightness. The catalogue of stars for 1880 contains 5,719 stars. M. 

 HouzEAXJ has examined the distribution of the stars in four wayr, : 1, 

 with respect to the solar equator ; 2, with respect to the direction of the 

 sun's proper motion ; 3, iierpendicular to this direction ; 4, with respect 

 to the milky way. No law whatever was found in the first three ways, 

 while the fourth mode of proceeding confirmed W. Struve's conclusion 

 that the density of stellar layers parallel to the jjlane of the milky way 

 decreases very regularly and gradually towards the poles of the latter. 



Julius Schmidt has, in (continuation of his researches on the colors of 

 stars, published an extensive series of color estimations, made chiefly 

 with the finder of the Athens refractor, from 1872-'78. Only for Arc- 

 turns has he been able, with any certainty, to find a variation of color. 

 It is mostly very bright stars he has observed, and he investigates the 

 difference in the estimation, according to whether the finder or the re- 

 fractor was used, and finds a greater difference the nearer the color is to 

 white. 



A " new star" of 8.8 mag. was found in November by Mr. Baxen- 

 DELL, according to two Dun Eecht observations in 7'' 34"^ 45^07 -|- 8° 39' 

 39". 6 (1879.0), According to Vogel, the spectrum is verj- remarkable, 

 with mauy dark bands, especially in the more refrangible part. 



PARALLAX OP STARS. 



Nearly the whole of Part III of the " Astronomical Observations and 

 Kesearches made at Dunsink" is devoted to annual i)arallax. The first 

 paper contains a discussion of observations of the planetary nebula H. 

 IV. 37 from August, 1871, to August, 1872, by Dr. BrIjnnow. The 

 nebula has in the center a well-defined point resembling a star of the 

 eleventh magnitude. This was compared in declination with a star 

 of the tenth magnitude, and the parallax was found to be perfectly in- 

 sensible, a result which agrees well with that of a similar series of ob- 

 servations by Professor Bredichin, of Moscow. 



A notice of a?i elaborate paper by Dr. Elkin on the paraUax of Alpha 



