(149) 
oat a method to calculate^ what depth is to be concluded 
from a ay other time of the like Globes ftay under water. 
In the jfame Tryals^made with this Inftrumeot in the faid Ri- 
ver of Thames, it has been found, that there is no difference in 
time, between the fubmerfions of the Ball at the greateit 
depthjWhen it rofe two Wherriesicngth from the place where 
it was let fall (being carried by the Current ctf the Tide) and 
when it rofe within a yard or fo of the fame place where it was 
letdown, 
The^^^^r Inftrument, for Fetching up water from the depth 
of the fea, is (as appears by Figure 2.) a fquare woodden B//r- 
%rC,-whofe bottoms EE, are fo contrived, that as the weighc 
A, finks the Iron 6^(10 which the Bucket C^is faitncd by two 
handles DD, on the ends of which are the moveable bottoms 
or Valves EEj':ind thereby draws down the^Buckct; the refi- 
ftance of the water keeps. up the Bucket in the pofture d 
whereby the water hath, ai! the while ir is dcfcending, a clear 
paffage through i whereas.as foon as the Bucket is pulled up- 
wards by the Line F^rhe refiftance of the water to chat motion 
beats the Bucket downward ^ and keeps it in the pofture 
whereby the Included water is preferved from getting out^ 
and the Ambient water kept from getting in. 
By the advantage of which Veffei ; it may be known, whe- 
ther fea water be Salter at and towards the bottom, then at or 
near the top : Likewife^whether in fome places of the fea^any 
fweet water is to be found at the bottom i ihQ Affirmative 
whereof is to be met with in ihQEaJl Indian Voyages of the in- 
duftrious John Hugh Van Linscheten. who page 1 6 of that Book, 
as 'tis Englijhsd^ rccordsj ihd,i in ihtFerfianCulph^ about the 
Ifland Barem, ot Baharem, they fetch up with certain Veflels 
(which he defcnbes not) water out of the fea^ from under the 
fait- watefj fo-ur ©r fiv@ fathom deep., as fweet^ as any Fountain 
water. 
X 
Of 
