PRESIDENT'S ADDRESS. Ixxv. 



the constellation of Aquila, designated Nova Aquilm, No. 2 ; 

 and there is probably also one in Ophiuchus. It has been found 

 that a star in the large Magellanic cloud has a large proper 

 motion of 1.2 second in a year. This was discovered by 

 the ingenious device of superposing a photographic plate on a 

 glass positive of the same region taken some time before, 

 which would show nothing which had not moved in the 

 intermediate period. The plate showed about 300,000 stars! 

 Professor Kapteyn finds that those stars whose proper motion 

 has been determined, move in opposite directions in the line of 

 the Milky Way, which suggests that they are rotating round a 

 central axis. 



From the fact that meteoric matter has been found at a depth 

 of 500 feet below the surface of the large crater in Coon 

 Mountain, Arizona, and for other reasons, it is concluded that 

 this crater is the result of the impact of an immense meteorite, 

 the fragments of which are well known as Canon Diablo 

 siderites. 



A new and important observatory has been established on 

 Mount Wilson, in South California, at a height of 6,000 feet, in 

 an exceptionally clear and dry atmosphere. Besides other 

 advantages, it will be well furnished with instruments, including 

 a very powerful telescope. 



An account of the geodetic survey in South Africa was laid 

 before the British Association, the extreme accuracy of which 

 is shown by the discrepancy in measurements of a base of 

 70,000 feet being only one in 1,500,000. More recently 

 measurements have been made with great success with wires 

 composed of invar, an alloy of steel and nickel which does not 

 vary with the temperature. Greenwich time has been adopted 

 as a standard by several countries, including North America, 

 which divides itself into five zones, which are, respectively, four, 

 five, six, seven, and eight hours slow on Greenwich. France 

 is again considering the matter, and, it is hoped, may bring 

 herself into uniformity with the greater part of Europe in this 

 respect. 



