ASTRONOMY. 



171 



of the closest known ; ' ninsniiudes 0.0 and 0.2. With a power of 1,400 

 there was only a diglit elon,ua-Tiou. 



" 2. B. A. C. 346; Mr. Burnbam thinks the principal star may be va- 

 riable, and he is certainly correct in his surmise. Heis gives it as a 

 naked-eye star O.-^T, Gould 7.™0, and it has been several times noted 

 8=^; while the writer has recorded it as low as 9™. 



" 3. /3 117 ; a star with a proper motion, according to Argelander, of 

 0".438; measures in 1883 show a coiiinion motion of the components; 

 their distance is 2". 2. 



" 4. : Sagittarii ; detected by Winlock, probably a retrograde motion 

 of 225° in less than fourteen years ; and evidently a change of 48° in 

 less than three years, by Mr. Burnham's measures alone. It is an ob- 

 ject for large instruments in the other hemisphere. 



"5. /9 Delphini (/5 151).— A very rapid binary; since its detection by 

 Mr. Burnham, in 1873, there has been an increase in the angle of about 

 180O, and a diminution in distance from 0".0 to 0'^25. He thinks ' it 

 may prove to have, with the single exception of o Equulei, the shortest 



period known.' 



" Mr. Burnham collects the measures of o Eqnulei, and infers a 

 period of revolution of about 10.8 years. Measures should be easy 

 again in 1885. 



" 6. 85 Pegasi {[i 733) —The close pair was not measurable in 1882 ; the 

 angle was about 333° at the epoch 1883.75. The mean annual motion 

 is about 120.5, at which rate the period would be less than thirty years. 



"In the introduction to the catalogue will be found references to the 

 publications where the thirteen previous ones are to be found." {l^ature.) 



MOTIONS OF STARS IN THE LINE OF SIGHT. 



From the Astronomer Royal's report we learn that— 

 " For the determination of motions of stars in the line of sight, 412 

 measures have been made of the displacement of the F line in the spec- 

 tra of 48 stars, 91 measures of the h lines in 19 stars, and two measures 

 of the D lines in one star, besides measures of the displacements of the 

 h and F lines in the spectra of the east and west limbs of Jupiter, and 

 in the spectra of Venus and Mars, and comparisons with lines in the 

 moon or' sky spectrum made in Ihe course of every night's observations 

 of star-motions, or on the following morning, as a check on the adjust- 

 ment of the spectroscope. Some preliminary measures have also been 

 made of the F line in the spectrum of the Orion ifebula. The progress 

 ive change in the motion of Sirius, from lecession to approach, alluded 

 to in the last two reports, is fully confirmed by numerous observations 

 since last autumn, and a change of the same character is indicated in 

 the case of Procyon. A discussion of the measures of all the stars ob- 

 served here, on which I am now engaged, shows that the results of the 

 four periods- 1875, June, to 1877, May; 1877, June, to 1880, December; 

 1881, January, to 1882, March 10 ; 1882, March 11, to 1884, March 31 ; m 



