AMERICAN 
JOURNAL OF SCIENCE AND ARTS, 
[THIRD SERIES] 
Art. XXVIL—On the Number and Distribution of the Bright 
Fixed Stars ; by B. A. GOULD. 
' (Read before the American Association for the Adv. of Science, Aug. 17, 1874.) 
THE magnificent work of Argelander entitled “ Durchmus- 
terung des nordlichen Himmels,” is w own to lovers of 
astronomy. His problem was no less than the formation of a 
complete list of all the stars of the northern hemisphere to 
the ninth magnitude inclusive, together with as many as possi- 
ble of the 9-10 magnitude. The undertaking was successfully 
carried out, affording not only an exhaustive series of charts, 
but likewise a “ working-list,” which an association of northern 
observatories is now employing for the determination of the 
accurate positions of the 815,000 stars which it contains. It 
furthermore records the aspect of the visible heavens, at the 
time, with an accuracy amply sufficient for all purposes whic 
do not require minute precision. : 
In this work, the magnitude of each star was estimated to 
the nearest half unit as it passed through the field of view; 
and since all the stars were observed more than once, and most 
of them several times, the mean of the several estimates was 
taken and is given in the published catalogue to the nearest 
tenth of a unit. In 1869 Professor Littrow of Vienna made a 
careful enumeration of the number thus given for each degree 
of magnitude, in order to ascertain’ how far the results would 
Indicate an approximate uniformity of distribution for the stars — 
lying within the portion of space under consideration. 
Am. Jour. Scr.—Tutrp Series, Vou. VIII, No. 47.—Nov., 1874. 
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