C 381 ] 
Ample cafe j we will fuppofe the wheel immoveable, 
or that c o, and proceed to inveftigate, whether, 
fuppofing the number of float-boards to be greater, 
the ium of the effects will come out greater or lefs 
than what refults from one fingle float-board placed 
vertically. 
In order to a general folution of this queftion, we 
will fuppofe two float-boards CD and CE fig. 4, 
making any angles with the vertical, and let us com- 
pare the effedt of the fingle float-board GD with the 
effect refulting from the float-boards FEand GD 
taken together, which will be reduced to FE and 
OD, becaufe the part OG becomes ufelefs, as the 
ff ream is intercepted by F E. Let CB — CD 
— CE a, CA =f colin. BCD = m, cofin* 
BCE = [A y which gives CG - CF=^ and 
m y. 
CO — ^ a. Then we fhall find, by § VI, the 
effedt of G D ~ — - -- - (tn muu — ff) that of O D 
tl&VV . . . . 
— q " {mm act — fiftctu). and that of FE 
— ~j~ {ft ft act — ff)', whence it appears, that the 
fum of the two laft is exadtly equal to the fir ft, 
which will ever hold good whatever be the value 
of/. 
Whence arifes the following theorem : 
Whether the wheel he plunged quite up to the axle, or 
only in part jo, provided it be immoveabUy and that one 
of its jhat-hoards be placed vertically , its ejfeffi will be cgh- 
Jlantly the fame y whatever be the number of float-boards 
oppofed to the f ream, even though it were infnite. 
The 
