satellite are one millioa, seventy-four thousand, one hundred 

 miles, and eij^ht hundred and forty thousand, six hundred miles ; 

 the Sliced of the former in its orbit is twenty-seven miles per 

 second, and of the latter, fifty-six miles j)er second. Eouffhly 

 speaking, Algol is less than half the mass of the sun. The 

 obirervations of Mr. Monck, of Greenwich, confirm those of Pro- 

 fessor Vogel. 



Mr. Isaac Roberts, the celebi-atcd amateur photographer, has, 

 by means of his stellar photographs, done good work in deter- 

 mining the variability of Algol, and similar stars. By his method 

 all atmospheric, actinic, and chemical changes are eliminated ; 

 thus the study of the variability of the stars can be pursued under 

 the most favourable conditions. 



A novel apparatus has been fixed to the Great Lick Telescope, 

 by means of which it is hoped that still better photographs may be 

 taken of the moon, which will yet farther increase our acquaintance 

 ■with our satellite. Professor Holden has already taken five 

 photographs of the successive phases of the moon which give an 

 admirable representation of the long lunar day, from sunrise to 

 sunset. These photographs are published in America at popular 

 prices. Some superb photographs of the moon, which show the 

 lunar craters in the most striking manner, have also been taken in 

 Paris, by M. M. Paul and Prosper Henry. 



Theophilus, the deepest of the lunar craters, and whose diameter 

 is sixty- four miles, is seen standing up eighteen thousand feet 

 above the chasm. The diameter of these photographs is over 

 one yard, and they are said to surpass even those from the Lick 

 Observatory in clearness of definition. 



From Grahamstowu last autumn was reported the discovery of 

 a new comet, or at any rate of one whose orbit brought it for the 

 first time within our view. It appeared at 7.45 p.m. on October 

 27th, on the western horizon, and after performing a rapid 

 journey of at least ninety deorees it disappeared in the south east 

 at 8.32 p.m., having only been visible for about three quarters of 

 an hour. When first seen it was about thirty degrees in length, 

 but it soon attained the length of ninety degrees, and stretched 

 along the southern horizon like a " ribbon of weird grey light." 

 This comet possessed no visible nucleus, and was of extreme 

 tenuity, for the lustre of several bright stars, across which it 

 passed, was not diminished by its transit. The moon at the 

 time was at the full. 



A remarkable meteor is said to have passed over Iowa last May, 

 having a comet-like tail. Its passage was accompanied by a 

 rumbling hissing noise, and it burst some eleven miles from 

 Forest City. The fragments which were scattered over the 



