('148) 
Firft^ for the founding of depths without a Gord , confider 
Figure and accordingly take a Globe ©f F/Vr, or M^sr/^/^ 5 
other light Wood , as A: let it be well fecured by Vernifh,^ 
Pitch, or othervyife,from imbibing water ^ then cake a piece of 
Lead or Stone, Dj confiderabJy heavier then wiU fink the 
Globe : let there be a long Wire-ftaple B^in the Ball A , anda 
fpringiiig Wire C, with a bended end F, and into the (aid fta- 
ple, prcfs in with your lingers the fpringing Wire on the- 
bended end : and oi^ it hang the weight D, by its ring E , and 
fo let Globe and all fink gently into the water^ in the pofture 
reprefcnted in the firft fn:^^^^, to the bottom,where the weighr 
D touching firft, is thereby ftopt ; bat the Ball , being by the 
it acquired in defcending, cHrried downwards a little 
after the weight is ftopt, fnfFers thefpringingwiretofly back, 
and thereby fets it felf at liberty to reafeend. Aud, by obfer- 
ving the time of the Ball's ftay under water ( which may be 
done by a Watch, having minuts and fecondsj or by a good 
Minut.glafs, or beftof all, by a Pendulum vibrating feconds) 
you will by this way , with thehelpof fom-eT^W^/, come to 
know any depth of the fea. 
Note, that care muft be had of proportioning- the weight 
and Hiape of the Lead, to the bulk^weightjand figure of the 
G!obe,after fuch a manner, as upon experience fliall be found 
inOrft-convenienti 
In fome of the Tryals already made with this Inftrument, 
the Globe being of Maple- wood , well covered with Pitch to 
hinder foaking in^ was 3tl inches in diameter, and weighed 
3 i pounds: the Lead of 4t pounds weight, was of 2i Conical 
gure, II. inches long, with the iharper end downwards^i flin- 
ches at the top^ and ^6 at the the bottom in diameter. And in 
thofe Experiments,iKade in th^Thames, in the depth of 1 9*fooc 
water, there pafled between the Irnmerfion and Emerfion of 
the Globe, 6^ feconds of an hour 5 and in the depth of icfoot 
water^there paffed 3^ feconds or thereabout : From many of 
which kind of Experiments it will likely not be hard to finde 
out 
