58 The Lunar Crater Linne. 



two occasions, though in opposite directions, would not be 

 materially different. Taking into account the disparity of 

 optical means, it must have been very much more luminous in 

 the latter observation. The site deserves an especially careful 

 scrutiny under varied solar illumination. 



But this, though the whole of the evidence as to this par- 

 ticular district, is not all that has recently come before us. 



1865. Nov. 24, about 6§h. p.m, the Eev. W. 0. Williams, 

 of Pwllheli, N. Wales, perceived, with a 4 T \ in. object-glass, 

 " a very pretty speck of light * * very much like a star of the 

 8th mag., but quite distinct and clear," which he observed for 

 about I4I1. with different eye-pieces, and saw better with 60 

 and 80 than with higher pov/ers, though it was well seen even 

 with 200. He showed it also to a friend, and one of his 

 daughters found it quite independent of his directions. From 

 careful allineation he believed its site to be at or very near 

 Carlini (128), a small crater in the M. Imbrium, a neighbourhood 

 which likewise ought to be studied in detail. As the moon 

 was on this occasion 6J days old, the brightness of the spot 

 must have been very considerable to have made itself so readily 

 distinguishable. 



A review of the whole of these statements seems to 

 establish the fact that outbursts of native light are visible 

 from time to time on the night side of our satellite. At present, 

 it can hardly be said that the attempt to identify their sites 

 with foci of volcanic action has been unsuccessful, because an 

 attempt has never hitherto been made in. a manner likely to 

 ensure success. Schroter's investigation was carried on upon 

 unknown ground : his larger crater was probably not a crater at 

 all ; the novelty of his small ones rests on evidence which would 

 prove too much ; and till of late the inquiry has been in 

 abeyance. It should not remain so longer. 



THE LUNAR CRATER LINNE. 



Since the truly remarkable announcement in our last 

 number by Schmidt, of the change in the crater Linne, neither 

 the state of the air, nor the position of the terminator have 

 been as favourable as might be wished for the careful examina- 

 tion of this object. However, the following observations may 

 be thought sufficiently interesting for publication, till such pirne 

 as many of our readers, we hope, will be able to do better by 

 it themselves. 



1866. Dec. 13, 8h. Silvered reflector, 9J inches, by 

 With, power 240. Sky clear, but moon very low, and definition 

 tremulous. Terminator about l-£ diam., E. of Arirtoteles ; 

 2 diams., B. of Eudoxus, and through E. edge of M. Serenitatis. 

 " About J of the way from a marked high mountain on N. 



