( 2 47 ) 
clofe on all Tides, even where the Axis of the Machine 
pafles through. 
The chief Obje&ions againft this Invention, Teem 
to me fufficiently obviated by Mr. Du Qitets Memoir : 
But tho’ the whole of what is objected diould indeed 
prove, That a Vedel made for failing, as the com- 
mon Gaily, would be fo incumber’d with the Ma- 
domes , as to make the Ufe of Sails impracticable ; yet 
if it Hill holds true, that Hie will move fader ; as ap- 
pears, both by Reafon and Fact ; it mud be allowed, 
that a Vedel might be fo commodioudy condructed, 
to carry thefe Machines , as to go as fad as a Gaily in 
a Calm, and better endure the Weather when under 
Sail. 
Such a Vedel would have feveral Advantages above 
a Gaily, both in Sailing, and in Fight ; not to men- 
tion the Conveniences of lodging the Crew. She 
may put off to Sea any where, and thereby avoid the 
Dangers attending the Coad-Winds, which Gallies find 
to be a*head as foon as they have doubled certain 
Capes ; and fo they find themfelves between two 
Winds, which there would be no Danger of, farther 
out at Sea. With relpecd to Fight, die may mount 
Cannon fore and aft, and on each fide ; and even Mor- 
tar- pieces. In Time of Battel, die would be of won- 
derful Ufe ; for die would take and maintain her Pod 
without Admittance, either at the Head, or the Rear of 
the Enemy’s Line, and there make ufe of her Bombs : 
Befides the Advantages of towing off other Veffels 
from their Danger in a Calm, and of boarding, or 
making off from the Enemy. And this holds in Ships 
of any Rate ; provided the length of the Oars, the. 
Breadth 
