[ 156 3 
languid Current toward the other j that is, the Tide, 
along that Side of the Ifland, will fet longer one 
Way than the other. 
If a ftrong Stream of Tide runs acrofs the Mouth 
of a Bay that docs not reach far into the Land ; 
within that Bay there will be a flow Stream fetting 
the contrary Way. Or, if a ftrong Stream fets di- 
rcftly, or nearly fo, along the Extremity of a Point, 
or Promontory, that ftretches ftrait out from tire 
Conft, between this Stream (before it reaches the 
Point) and the Coaft, there will be a languid Cur- 
rent with a contrary Dire&ion. By attending to this, 
one Vcflel may keep her Courfe, or gain a Port, 
while another is carried away with the Tide. 
If a fmall Ifland lies thwart a Tide-way, that Part 
of ihe Stream which runs along one End of it, will 
join what runs along the other, at lomc Diftance 
beyond the Ifland, inclofing between them a curved 
Space, within which there will either be no fenfible 
Current, or a flow one, contrary to the other Streams. 
The counter Current, in the middle of this almoft 
flagnant Space, or Eddy, when it gets near the Ifland, 
fplits in two; one Branch of which runs towards 
one Extremity of the Ifland, the other towards its 
other Extremity; where meeting the ftronger direct 
Streams that form the Eddy, are by them again car- 
ried towards its Vertex. 
Thefe Eddies may be of great Service to 
Ships or Boats, by fheltering them from a rapid 
Stream, or even carrying them againft it ; or may 
enable them to crofs it with more Advantage, ac- 
cording to the different Places to which they are 
"bound. The Oppofition of the contrary Tides 
bounding 
