( 1072 ) 
fmall part of Time accurately, nearer than to a quarter 
of a Second ( made and contriv’d by Mr. George Graham, 
an ingenious Clock-maker) and with an r Second Pen- 
dulum: And the differences of Time between the fall of 
the Leaden Balls and the other Balls were taken below, by 
the Prefident, Martin Folkes E(q; F. R. S. and another 
Perfbn,whoall agreed in their Obfervations of the Time, 
which they made each with an half Second Pendulum*. 
The following Table gives the Marks, V, ^eights, 
and Diameters of the feveral Balls, in three 
Columns. 
Leaden Balls 
Troy iVtight, 
Diameters in In:hes 
L oz. d. 
and Decimals, 
1 c 
1 : I : f 
1 , I 
1 C 
I : 11 : 4 
* » 99 
3 ^ 
I : 1 1 : 11 
1 , 0 
AC 
I : 1 1 : 1 1 
1 , 0 
sc 
I : 1 1 : 11 
1 , 0 
6 c 
I : 10 : 0 
I ,98 
Pafthoard Balls. 
> 
A 
0 .* 3:6 
S , S 
B 
0 .* 1 .* 14 
5 , I 
C 
0 .* 1*17 
S * * 
Glafs Balls, 
D 
0 .- 3 - 13 1 
3 > 9 
E 
0 .• 3-: 
5 » 42 - 
F 
0 .* 6 : 0,- 
5 ,SS 
N,B, The Polar and Equatorial Diameters of the 
Glafs Balls being different, I have fet down a Mean 
Diameter for each of them ; the true Diameters are thus, 
of D 4 ^ 3)8. of E 5-, 6 and ^,2.5. of F f,7 & 5,4 Inches. 
the 
