REPORT ON ASTRONOMY. 
147 
part, and sometimes perhaps to have been formed from them,) 
which have since been generally received. The additions made 
to the subject since that time consist of little more than accumu¬ 
lations of observations (with the exception of one set of deduc¬ 
tions, of which I shall speak presently). Sir W. Herschel’s last 
paper was a catalogue of 145 new double stars, without accurate 
measures, communicated to the Astronomical Society in 1822, 
and printed in the first volume of their Transactions. In the 
Dorpat Observations , some measures of the positions and di¬ 
stances of double stars were given, and a catalogue of the places 
of 795 double stars, from all authorities, but without measures. 
Some were also observed by Bessel, and a catalogue of 257 is 
given in the Konigsberg Observations part 10, and in the Ast. 
Nachr . No. 88, with estimations of distance, but no angles of 
position. In 1827, Struve published his Catalogues Novus , con¬ 
taining the places of 3112 double stars; not measured, but 
classified by estimation of their distances. This work (the fruit 
of two years’ labour, with Fraunhofer’s large telescope,) contains 
all the double stars of a certain description to 15° S. declination. 
And though the want of measures renders it inapplicable for 
the speculations which had been and are now grounded upon 
measures only, yet this must always rank as a very valuable 
catalogue. While this was going on, Sir John Herschel and 
Sir James South published (in the Phil. Trans . 1824,) accurate 
measures of 380 double and triple stars. Sir James South 
published {Phil. Trans. 1826,) measures of 458, and a re¬ 
examination of 36 of the former list; and Sir John Herschel 
added remarks on the changes apparently going on. There 
can be no doubt of the very great value of these determinations. 
Amici however, in Zach’s Correspondance , vol. 8, has called in 
question the accuracy of some of the measures. In the Mem. 
Ast. Soc. vol. 2. is a comparison, by Struve, of his own measures 
with those of Herschel and South. In 1826, Sir John Herschel 
presented to the Astronomical Society a catalogue of 321 new 
double stars, the distances and positions being given by estima¬ 
tion, with remarks on the great nebulas of Orion and Andro¬ 
meda; in 1827, one of 295 stars; in 1828, one of 384. About 
the same time Mr. Dunlop published measures of 253 southern 
double stars {Ast. Soc. Mem.), and remarks on the southern ne¬ 
bulae {Phil. Trans.). In 1830, Sir John Herschel communicated 
good measures of 1236 stars, made with a 20-feet reflector ; 
and lately, in vol. 5. of the Ast. Soc. Mem. he has given accu¬ 
rate measures of 364 with an achromatic telescope. This last 
paper is the most interesting that has been mentioned, ex¬ 
hibiting all the most striking results as to the motion of double 
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