t
possible to stand on the summit of one of these elevations. It is
doubtful whether Bessel has a central mountain. Neither Madler nor
Schmidt have seen one, though Webb noted a peak on two occasions. I fail
to see anything within the crater. The bright streak crossing the Mare
from N. to S. passes through Bessel.

LINNE.--A formation on the E. side of the Mare Serenitatis, described by
Lohrmann and Madler as a deep crater, but which in 1866 was found by
Schmidt to have lost all the appearance of one. The announcement of this
apparent change led to a critical examination of the object by most of
the leading observers, and to a controversy which, if it had no other
result, tended to awaken an interest in selenography that has been
maintained ever since. According to Madler, the crater was more than 6
miles in diameter in his time, and very conspicuous under a low sun, a
description to which it certainly did not answer in 1867 or at any
subsequent epoch. It is anything but an easy object to see well, as there
is a want of definiteness about it under the best conditions, though the
minute crater, the low ridges, and the nebulous whiteness described by
Schmidt and noted by Webb and others, are traceable at the proper phase.
As in the case of Hyginus N, there are still many sceptics as regards
actual change, despite the records of Lohrmann and Madler; but the
evidence in favour of it seems to preponderate.

CONON.--A bright little crater, 11 miles in diameter, situated among the
intricacies of the Apennines, S. of Mount Bradley. It has a central hill,
which is not a difficult object.

ARATUS.--One of the most brilliant objects on the visible surface of the
moon, a crater 7 miles in diameter, S. of Mount Hadley, surrounded by the
lofty mountain arms and towering heights of the Apennines. A peak close
by on the N. is more than 10,000 feet, and another farther removed
towards the N.W. is over 14,000 feet in altitude.

AUTOLYCUS.--A ring-plain 23 miles in diameter, deviating considerably
from circularity, W. of Archimedes, on the Mare Imbrium, or rather on
that part of it termed the Palus Putredinis. Its floor, which contains an
inconspicuous central mountain, is depressed some 4000 feet below the
surrounding country. With a power of 150 on a 4 5/8 achromatic, Dr.
Sheldon of Macclesfield has seen two shallow crateriform depressions in
the interior, one nearly central, and the other about midway between it
and the N. wall. Th