1005 



creased attention ; many very able men are springing up, and an 

 association for the advancement of science has been formed and is 

 well supported. Several observatories, furnished with the best in- 

 struments, principally from the manufactories of continental Europe, 

 have been established. An astronomical expedition has been sent 

 to the southern hemisphere, by authority of the federal government, 

 under the command of Lieut. Gillies, principally for the 'purpose of 

 making observations, which, used in conjunction with others in the 

 northern hemisphere, may determine more accurately the parallax 

 of the sun and the dimensions of the solar system. No observations 

 have yet been receive(f from the expedition, but it is known that an 

 observatory has been established for its use at Santiago. 



Much also has been done by the labour of private persons : an 

 astronomical journal of great merit has been established; and seve- 

 ral of the investigations published in it, as, for instance, on the velo - 

 city of the galvanic current, on the elements of Neptune, and on 

 # the wonderful comet of 181^3, will probably be considered as 

 standards. 



One of these deserves especial mention. It is known that Bessel's 

 examination of the places of Sirius and Procyon for many years 

 past led him to the conclusion that these stars are subject to the 

 action of some unknown force, and he suggested the attraction of 

 invisible companions ; now lately M. Schubert has examined, in 

 the same way, the movements of Spica, and has com^e to the conclu- 

 sion that it moves in an apparently small orbit, with a periodic time 

 of forty years. Such conclusions, it is unnecessary to observe, are 

 extremely doubtful, but the inquiries which have led to them are 

 deserving of our best attention. 



In the methods of observing, a step has also been taken by the 

 astronomers of the United States which deserves particular notice. 

 In a country in which the use of the electric telegraph is so exten- 

 sively developed, it was natural that the application of this mode of 

 instantaneous communication, to the determination of terrestrial 

 longitudes, should soon suggest itself ; indeed the principle had been 

 suggested by Mr, Wheatstone as far back as 1840*; and it was 

 then an easy step to make the galvanic wire an instrument for trans- 

 mitting, not the comparison of the clock, but the actual observation 

 of the transits over every individual wire of the transit telescope. 

 For this purpose it was necessary in a series of stations to place only 

 one moderately good clock, to be used in the following manner. An 

 endless fillet of paper being carried by independent mechanism, under 

 a style, which is pressed upon it by the action of a galvanic magnet, 

 that derives its force from a wire passing through all the stations, 

 and animated by a battery in any part ; if the clock be so connected 

 with the circuit that at every vibration of the pendulum the circuit 

 is interrupted, the trace made by the style upon the paper fillet will 

 be interrupted at every second. Now if at each of the observing 

 stations the wire be carried through such an apparatus that the cir- 



* Bulletin de TAcademie Royale de Bruxelles, 7th October 1840, and Comptes 

 Rendus, tome xx. p. 1554. 



