C 201 1 
Eclipfes of the three firft Satellites of Jupiter, ob- 
ferved, at the Royal Obfervatcry at Green- 
wich, in the years 1762, 1763, and 1764, 
during the time that the late Rev.Nathaniel Blils, 
A. M, F. R. S. Profeffor of Geometry in the 
Univerfity of Oxford, was Aftronomer Royal ; 
communicated by Nevil Mafkelyne, B. D. 
F. R. S. Aftronomer Royal. 
N. B. The obfervations were fometimes made with 
a 6 foot Newtonian refleder, the diameter of 
whofe aperture is 9 inches, and which magni- 
fies 100 times, and fometimes with a 2 loot 
refiedor, the diameter of whofe aperture is 4 4 
inches, and which magnifies 90 times ; and 
fometimes with another 2 foot refiedor, made 
by Mr. Bird, whofe aperture is 3,8 inches, 
which magnifies 88 times. 
The 6 foot telefcope fhews an immerfion of the 
firft fatellite later, and an emerfion of the fame 
fooner, than the firft of the 2 foot telefcopes by about 
2o // . The difference between the two 2 foot tele- 
fcopes may be fuppofed about 5". 
1 762 
f Aug- 
26 at 
T2 
5 i 
45 " 
1 Imm. of I 
l Sept. 
j 8 — 
9 
29 1 
0 a. 
4 — 
1 1 
3 ' 
26 I 
l 
J 
A 
-11 — 
13 
27 
9 J 
) N ov. 
3 — 
15 
48 
56 
little hazy 
1 
-2 1 — 
44 
41 a 
1 Dec. 
23 — 
4 
57 
40 
. fa tel. with 
telefcope. 
6 foot 
} 
Em. of I. with 6 
foot telefcope. 
D d 
■- Vox. LVIII. 
1 763 
