94 Sir J. Herschel’s Astronomical Observations 
Mason represents these avenues as free from any abrupt change 
of direction, the northern and the preceding of them branching 
out with an easy and graceful bifurcation from the southern; 
whereas my figure, whose correctness in this respect I cannot 
doubt, gives to the preceding avenue a remarkably sudden and 
uncouth flexure, like a gnarled branch of an oak, just at its diver- 
gence from the other two. ‘The southern nebulous mass, in my 
figure, has a considerably wider extension towards the preceding 
side than in Mason’s, which represents it as nearly round, but as 
this portion was very faint, there was probably not light enough 
in his telescope to render the whole visible.” The author adds 
in a note: ‘ The places of his stars being determined by numer- 
ous. and elaborate micrometrical measures, are no doubt more ac- 
curate than mine.” With this testimony to the refined accuracy 
of Mason’s observations, under all the disadvantages he had to 
contend with, his friends may wellsrest satisfied, although some 
slight discrepancies should be found between his delineation of 
this a and that of the great astronomer with which it is com- 
pared w that so many powerful telescopes are directed to 
the iia we probably may ere long have the means of deter- 
mining which of the two representations is the more correct. 
_ The great nebula in the Swan, which had been represented 
by the Herschels as consisting of two distinct. formations, Sir 
John admits that Mason has proved to be one and the same neb- 
ula,—a discovery imparting so pereanry a character to this 
rp: err considering all the circumstances, of so high an order 
of merit, that we are confident, had the author been writing of 
the sti nebule (among which this is found) instead of the 
southern, he would have given to it more than a passing notice. 
He also omits to mention, that Mason discovered in the vicinity 
of the 'Trifid a nebula before unknown, surrounding the star 22, 
ciaeedt near the south pole, “8 known under the a 
Magellanic Clouds ; and the laborious and patient attention which 
he bestowed upon them, and the magnificent figures by 
he has represented them, must, we think satisfy the most eager 
curiosity. ‘he appearance of the “Nubecule” to the naked eye, 
is not as splendid as Sir John had been led to pies by the 
glowing descriptions of voyagers in the southern “ The 
general appearance (he observes ) of these objects to the snaaibell eye, 
in aclear night, and in the absence of the moon, ( whose light com- 
1 ator effaces the lesser, and almost also the larger of them, ) i is that 
c ee sricncns nebulous patches of about the same inte 
with the Milky Way.” But the author has given his keadakerne 
ity of judging for themselves, having inserted among the 
