fhf, for the founding of depths without a Cord , confider 
Figure r, and accordingly take a Globe of Firr, or Maple , or 
other light Wood ^ as A : jet it be well fecured by Vernifh, 
PitCii, or otherwi fe,from iinbioing water * then take a piece of 
Lead or Stone , D, confidently heavier then will, fink the 
Globe ; let there be a long Wiredtaple B,in the Ball A , and a 
Springing VV' ire C, with a bended end F, and into the laid fta- 
pic, prcfs in with your fingers the fp ringing Wire on the 
bended end : and on it hang the weight D, by its ring E , and 
fo let Globe and all fink gently into the water, in the pofture 
reprefemed in the firft Figure, to the bottom, where tire weight 
D touching firft, is thereby ftopt ; but the Ball, being by the 
Impetus, it acquired in defending, carried downwards a little 
after the weight is ftopt, fullers the fpringing wire to fly back, 
and thereby Lets it felf at liberty to reafeend. And, by obfer- 
vitig. the time of the Ball’s flay under water ( which may be 
done by a Watch, having minuts and feepuds- or by a good 
Miniit-glafs, or befi; of all, by a Pendulum vibrating feconds) 
you will by this way , with the help of fome Tables > come to 
know any depth of the fea. 
Note, that care maft be had of proportioning the weight 
and lhape of the Lead , to the bulk,we!gh.r 3 and figure of the 
Globe, after fuch a manner, as upon experience fliall be found 
moft convenient. : - • 
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 yft inches in diameter , and weighed 
^ J pounds : the Lead of 47 pounds weight, was of a Conical fi- 
gure, 11. inches long, with the fharper end downwards, 1 & in- 
ches at the top., and ? 6 at the the bottom in diameter. And in 
diofe Experiments, made in th eTbam.es, in the depth of 1 $>,foot 
water, there palled between the Immerfion and Emerflon of 
she Globe, 6 ♦ feconds of an hour 5 and in the depth of 1 o.foot 
water^there paflfed feconds or thereabout : From many of 
which kind of Experiments it will likely not be hard to finde 
