fame Manner as thofe defigned for Windmills i only* 
in thefe the Extremity of their Ends (lands parallel 
to the Planes of each End of the Axis , thofe Ends 
I mean which are placed fartheft from the Centre. 
This hexangular Axis, when employed, muft be 
placed parallel to the moving Stream, and may lie 
even with its Surface : But the Engine will aft mod 
vigoroufly, when it and all the Sails employed are 
intirely under Water, as is eafy to comprehend. 
Each Set of the Sails before del'cribed contains 
Ex in Number, and are fo contrived as to be put in 
and taken our at Pleafure 5 whence it follows, that 
when a Engle Set of Sails is made ufe of, the En- 
gine produceth a Engle Effed, when two Sets a dou- 
ble, and fo on, till the defired Momentum is acquired, 
with the fame Quantity of running Water, provided 
there be Room to fix a fufficient Number of Sails. 
It is farther to be obferved, that when this Engine 
is placed with its Sails made and weathered as above 
diredted,. they will move with equal Velocity, even 
fuppofing the Current fhould change its Courfe, and 
come upon them in a quite contrary Diredion, as 
the Cafe really happens in Rivers where the. Tide 
ebbs and flows j where moft other Engines yet in- 
vented are of little Service. 
About fix Weeks ago I had the Pleafure to fee a 
Model of this Engine tried. It was fixed in our 
River, in a Place where the Water moved only 
2 7 Feet in 20 Seconds 5 in which Time the firft 
Mover made Ex Revolutions. Its Diameter was no 
more than two Feet and two Inches 5 yet it would have 
lifted fourteen Pounds two Yards high in the above- 
mentioned 
