ss 
j 
; 
| 
: 
W. R. Dawes on the Telescopic Appearances of Saturn. 161 
a croaches 0:2 or 03 on the ring A.. By carrying my eye across 
from the black division on one side to the other, I can see that, if 
continued in an uninterrupted line, it would cut of a thin slice 
from the edge of the ball. With very high powers (705 to 1000) 
the difference of color of the southern edge of the ball, and the 
ring A at that point is more marked than with the lower powers ; 
and long scrutiny with them confirms my impression that the 
ball encroaches slightly on A.” 
*10 36"+G. M. T. Applied an excellent Huygenian eye- 
piece, giving power 860. It is admirable. The difference of 
color of the southern edge of the ball and ring A is obvious; 
and there is no doubt at all of the slight encroachment of the 
ball on its interior edge. Finding the light of the planet produce 
avery unfavorable effect upon my eye while endeavoring to es- 
timate the degree of encroachment of the ball on A, it occurred 
tome to apply my solar eye-piece for the purpose of excluding 
the rest of the ball and rings, and leaving visible only the south- 
ern portion of the ball and the adjacent portion of the rings A 
and B. Power 506 (the highest, a double-convex lens). The 
effect is admirable. My eye having rested upon it for some time, 
the outline of the southern edge of the ball was far more dis- 
tinetly seen than before, and leaves no doubt of its encroaching 
on the interior edge of A, to about 0’°3 by careful estimation. 
At times a little mottling can be discerned very near the southern 
limb of the ball. Its color is very different from that of ring A; 
and it completely interrupts the black division which comes 
sharply up to the ball on both sides of it.” 
5. The Shadow of the Ball on Ring B. On this appearance 
Thave noted as follows :— ; 
“1854, Sept. 26. The shadow of the ball on ring B is nearly 
a straight line.” 
On Sept. 29 the projecting 1. 
. * 
ball ; me oy : 
cutting off the acute point of the ring B intercepted between the 
Which the appearance is much exagg ; 
of the ball on rin i 
wu lo g Bis really a 
i on line, though nearly so. 
seems to a little curved 
ver towards the ball. 26 
Np Srnies, Vol. XXI, No. 62,—March, 1856. 2) 
SO hg > 2) 
