344 APPENDIX. 
cd and afccnded to greater Depths with the 
fame Velocity, it would reach to the Depth 
of a Mile in feventeen Minutes, and reafeend 
in the like time. But fince the buoyant Bo- 
dy may return fafter to the Surface of the 
Water than it defeended, therefore Eftimaces 
from the time of the Bodies keeping under 
Water will be very uncertain: Yet when fre- 
quently compared with the Eftimate which 
is made, from the height of the Water in 
the Gage-T ube 5 a Rule may perhaps be 
formed from thence, efpecially if the whole 
Machine be always the fame, and the (ink- 
ing Ballad: be always of the fame Weight and 
Size : As fuppofe the Ballad: were put into 
globular earthen Veflels, made all of the fame 
Diameter. 
zz. That the Sea is not many Miles deep 
is probable from hence, that all the great 
Oceans are here and there interfperfed with 
Idands 5 an Argument that though as far as 
the founding Line has reached, the jSea is 
found to be deeper and deeper, the farther 
from the Shore (chough with fome Uneven- 
nefs) which would come to a great Depth 
indeed if it continued on fo, from one boun- 
dary of the vad Oceans to the other ; but 
the 
