aters, about
9 miles in diameter, standing in an isolated position in the Mare
Foecunditatis just S. of the Equator. Madler represents them as similar
in every respect, but Webb, observing them in 1855 and 1856 with a 3 7/10
achromatic, found them very distinctly different,--Messier, the more
westerly, being not only clearly smaller than its companion, but longer
from W. to E. than from N. to S., as it undoubtedly is at the present
time. Messier A, however, as the companion is termed, though larger, is
certainly not circular, as sometimes shown, but triangular with curved
sides. It is just possible that change may have occurred here, for Madler
carefully observed these objects more than three hundred times, and, it
may be presumed, under very different phases. Messier A is the origin of
two slightly divergent light streaks, resembling a comet's tail, which
extend over the Mare towards its E. border N. of Lubbock, and are crossed
obliquely by a narrower streak. Messier and Messier A stand near the S.
and narrowest end of a tapering curved light area. There is a number of
craterlets and minute pits in the neighbourhood, and under a high light
two round dusky spots are traceable in connection with the "comet"
marking, one just beyond its northern, and the other beyond its southern
border, near its E. extremity.

LUBBOCK.--A brilliant little crater, about 4 or 5 miles in diameter, near
the E. coast-line of the Mare Foecunditatis. The region E. of this object
is particularly well worthy of scrutiny under a low sun, on account of
the variety of detail it includes. On the S.E. run three fine parallel
clefts, originating near the N. end of the Pyrenees.

GUTTEMBERG.--A very fine ring-plain of peculiar shape, about 45 miles in
width, with a lofty wall, broken on the N.W. by another ring-plain some
14 miles in diameter, and on the S.E. by a small but distinct crater. The
border presents a wide opening towards the S., which is traversed by a
number of longitudinal valleys, both the E. and W. sections of the wall
being prolonged in this direction. A fine crater-row runs round the outer
slope of the E. wall, from the crater just mentioned to the N. side of
the formation. It is best seen when the W. wall is on the evening
terminator. There is also a broad valley on the S. prolongation of the W.
wall. The central mountain is bright but not large. A cleft crosses the
N.W. side of the floor. North of Guttemberg there is a curious oblong