on the local arrangement of the celestial bodies in space. 337 
series of gaging powers have been proved to make their gra- 
dual telescopic appearance from the 12th to the 9oodth order 
of distances, should also be gradually of a different construc- 
tion, with regard to physical size and brightness, from those 
which we see with the naked eye. 
From the great diameter of the mirror of the 40 feet tele- 
scope we have reason to believe, that a review of the milky 
way with this instrument would carry the extent o.f this 
brilliant arrangement of stars as far into space as its pene- 
trating power can reach, which would be to the a^oodth 
order of distances, and that it would then probably leave us 
again in the same uncertainty as the 20 feet telescope. When 
I made some sweeps of the heavens with the 40 feet telescope 
with a magnifjdng power of 370, I found it necessary to re- 
duce the intended breadth of the sweep from one degree to 
30 minutes, and the great length of time this would have 
taken up to examine only the ecliptic, to which I had directed 
the telescope, soon proved that by continuing to use this in- 
strument for sweeping, I should have been obliged to neg- 
lect the necessary observations of the 20 feet telescope. 
The following observations are extracted from my sweeps 
to support a few general remarks relating to the construction 
of the milky way. 
Dec. 7, 1 785. Right ascension 4 h 39'. Polar distance from 
64° o' to 66° 12'. The straggling stars of the milky way 
seem now to come on gradually ; most of them are small. 
Right ascension 4 0 43'. They begin now to be intermixed with 
some large ones. 
This observation proves that the telescopic breadth of the 
milky way, considerably exceeds the extent which in our 
mdcccxvii. U u 
