Friedrich Wilhelm August Argelander. 117 
meridian-circle by Pistor, with telescope of 6-foot focal length, 
and a heliometer by Merz. For some years cometary observa- 
tions (a large number of which bodies appeared. about that 
time) and observations of the small planets—the long series of 
discoveries of which had then just commenced—oceupied muc 
of the time of the establishment. But in 1849 Argelander 
th 
of the Berlin Academy Star-Charts, which, however, after the 
over, they embraced only a limited zone. 
Early in 1852, therefore, Argelander resolved to commence 
that great Durchmusterung, or survey of all the stars of the 
Slading a large number somewhat fainter than that, with which 
his name will be for ever associated. The whole number of 
recorded in these zones, between the north pole and 2° 
co declination, amounting to 324,198, and this gigantic 
abor, including the la ing down of the charts and publication 
both of them and of the catalogues occupied Argelander and 
'S assistants until the year 1863. They are too well known 
Th = homers to make any discussion of them necessary here. 
Ba the seventh volume of the Sonn Observations, published 
1869, are some interesting investigations into the proper 
pe foun. escort lala Serres, Von. XII, No. 68.—Aveust, 1876. 
