104 Prof. Gautier on recent Researches relating to Nebulae. 
the meanwhile, to regard these as positive facts until they have 
been corroborated, especially by observers located in more favor- 
able climates and provided with optical apparatus sufficient for 
of Huygens. Dr. Lamont first mapped this bay, which had 
never been seen by Sir J. Herschel. The second is a nebulous 
bridge which crosses the Sinus Magnus, with a point of light 
concentrated towards its middle. Struve has seen it in winter, 
sometimes as Herschel and sometimes as Liapounoff represented 
it, with more concentration of light, but always much more 
extended than these two astronomers have drawn it, and very 
much diminishing the southern limit of the great strait. La- 
mont has represented it only with very feeble traces, and Bond 
has never seen it at all. The third is a nebulosity surround- 
ing star 75 of Herschel’s catalogue, and which appeared to 
Struve to be subject to great changes of brilliancy. The fourth 
part is a sort of straight canal, joining in a right line the dark 
space situated around the stars 76, 80 and 84 of Herschel’s cata- 
logue, with the northern border of the Sinus Magnus near the 
exterior limit of the bridge mentioned above. The canal, which 
had never been represented by any other observer, was distinctly 
seen by Struve, March 24th, 1857, although on other occasions 
he did not perceive the least trace of it. 
This astronomer adds, in closing his communication, that the 
over the Sinus Magnus “has no n seen by The assertion rests 0B 
no evidence excepting its partial omission in the published engravings of Prof, 
Bond 
We are authorized to say that this feature may be distinctly recognized in no less 
than five original sketches made by him on as many different dates in 1847 and 1848; 
previous to the publication of the engraving, as well as on the very ‘copy from 
which it occurs also in several drawings made more Tr 
