THE PROGRESS OF ASTRONOMY IN 1900. 
BY 
T. J. J. See. 
[Read before the Society March 2, 1901.] 
In a brief sketch of the astronomical work accomplished 
during the year 1900 mention can be made only of those re¬ 
searches which are known to the public, and even of these 
the notes must be very incomplete. Yet even an imperfect 
summary may be useful in calling attention to investigations 
which are worthy of more careful study. Many other in¬ 
vestigations whose importance is not yet fully realized will 
be passed over in silence. 
In connection with the sun, attention may be called to the 
determination of the solar parallax by the French Bureau 
des Longitudes from observations of the transit of Venus of 
1882. M. Bouquet de la Grye, who has just finished the re¬ 
ductions, discussed the work of five observers, who used 8- 
inch telescopes, two north and three south of the equator, 
following the method of Halley, which depends on the dif¬ 
ference of the observers’ latitudes, and reached as his final 
value ^ = 8".7996. This is practically 8".80, the value al¬ 
ready adopted in the principal national ephemerides. 
By the method of Delisle, depending on differences of longi¬ 
tude, observations at the ten stations south of the equator and 
twelve north of it, M. de la Grye finds values of 8".772 and 
8".778, which, however, he thinks should be given little 
weight in comparison with the value derived by Halley’s 
method. The French value of the solar parallax found from 
the transit of Venus of 1882 is therefore 8".80—, which may 
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