■(44I)- 
In thefame Trialsmade with this Inftrumeot inthe faid River of 
Thames^ it has been found , that there was no difference intim^ 
between the fubmerfions of the Ball at the grcateft depth ^ wh^n 
itrofe two Wherry's length from the place where it was let fall 
(being carried by the Current of the Tyde ) and when it rofe oneiy 
a Yard, or fo, from the fame place ^ where it was let down t And 
that it muft be fo in great depths and ftronger Currents^ is as certain^ 
as eafie to be demonftrated. 
And if it be a Hedged^ that it muft be known , when a Light Bo- 
dy afcends from the bottom of the Water to the Top , in what 
proportion of time it rifes 5 it may be confidered » that in this Ex- 
periment the times of the Defcent and Afcent are both taken and 
computed together 5 fo thatj for this purpofe ^ there needs not the 
nicety, which is alledged, 
OF other Experiments ofthis way of founding without aLine^ 
made by the Noble Lord Vifcount Breunker 5 Sir Rokrt 
Meraj Knight, and Mr. Hook^ in the Channel at Sheermfs^^ 
the following Account was given, vid. 
Weighed Ounc. Grains, 
AWoodenBall {A) 32 4 co 
AnotherWoodenBallC-g)— 30 22 
A Lead ( A') - — jo ; go 
Another Lead ( B ) ~- i 00 ■ 
TbeiBall ( j.^ and theLead {iB ) werelet down at i$ htbom%. 
and th^ Ball returned in 48 fingle^ftiokes oif ZtPendu ium ^:hdi la- 
the h^.nd 5 -vibrating 5 8 iingle ftrokes in ^ Miymte , 
Afecond time repeated with the fame fuccefs 3 therefore ^ the 
motion was 4 foot every fecond. 
Again the Ball ( ^ j and the Lead ( S j whofe Nail was bended 
into a lharper Angle 5 the Bali returned in 39 ftrokes, . A: fecond 
time repeated with the fame fuccefs, at the fame depth. : * . ^u:^^ 
Ball {B) Lead ( J5 ) in which trial the Line^ not being dear, 
flopped a little the motion j the Ball returned in 47 at the fame 
depth, Mmm BaU 
