442 Lunar Details. 



region. Tet a view of the vicinity, which I subsequently 

 obtained on April 21, enabled me to add a few features, some 

 of which, at least, it is strange that they should have over- 

 looked. It is now to be regretted that the sketch in the 

 February number did not include a wider area, so as to give 

 room for a more interesting comparison; our purpose, how- 

 ever, will be sufficiently answered by the accompanying 

 diagram, in which the lettered objects only are to be found in 

 the map of B. and M. 



With a power of 212, and very good definition in my 

 5|-inch achromatic, I distinctly perceived that the upper part 

 of the ridge running down into the interior of Aristoteles, 

 from the peak close to the breach in the S.W. wall, was really 

 a chain of small craters, probably four or five in number. 

 This, however, was of course an object of such delicacy, as to 

 form no ground of inference. One of the lava-currents (?) 

 issuing N.E. appeared as a very minute furrow, beginning at 

 about -f- of the diameter of the great ring from its summit as 

 a little crater, probably broken down outwards, and running 

 in a slightly curved direction for about an equal distance, with 

 an aspect of irregular depth, as though it might possibly 

 prove, under more favourable circumstances, to be a confluent 

 chain of craters. Between B. and M.'s A (at the bottom of 

 the diagram) and their two hills T is a curious group, consist- 

 ing of a conspicuous pair of little contiguous craters, the 

 larger N, with a smaller companion B, two unequal hills N. 

 and another W. The ring B, of B. and M. has some irregu- 

 larity within it, unnoticed by them. S.W. of it, about {- of 

 the distance to the ring of a, but W. of the line, is a minute 

 but conspicuous crater : between this and the wall of Aristo- 

 teles are several others still smaller, of which a mere idea is 

 given in the sketch, as well as of a number of others to the 

 S.W., the grouping of which seems to point to a, as their 

 focus of action. N. of JEudoxus A (the most southern crater 

 in the sketch) were several others; and on the whole the 

 neighbourhood of Aristoteles was more like that of Copernicus 

 than would have been imagined from B. and M.'s map. The 

 W. of their two hills marked T either is a regular crater, or 

 has a cavity on its summit. — April 23, 24, 25, the furrow could 

 still be seen, though with decreasing visibility: the group of 

 three craters between A and T remained conspicuous. April 

 28, I could still see the pit on the summit of the western F. 

 All these objects therefore are confirmed, and the group of 

 little craters in particular is shown to be an object of per- 

 sistent visibility under varied illumination. 



This assemblage of three craters and thi*ec hills had been 

 previously discovered, together with several other very minute 



