[ 157 ] 
fore be fufficient for practical eflimation, without any 
allowance. 
Maxim jtfu When fails are loaded fo as to produce 
a maximum at a given velocity , and the velocity of 
the wind i?icreafes i the load continuing the fame ; 
J ftly, Tdhe increafe of effedl , when the increafe of the 
velocity of the wind is fmall, will he nearly as the 
fquares of t ho fe velocities : idly , When the velocity of 
the wind is double, the ejfedls will be nearly as io : ij\: 
But , 3 dly, When the velocities compared , are more 
than double of that where the given load produces a 
maximum , the effects increafe nearly in a Jimple ratio 
of the velocity of the. wind. 
It has already been proved, maxim i ft and 2d,, 
that when the velocity of the wind is increafed, the 
turns of the fails will increafe in the fame proportion, 
even when oppofed by a load as the fquare of the ve- 
locity j and therefore if wanting the oppofition of an 
increafe of load, as the fquare of the velocity, the 
turns of the fails will again be increafed in a fimple 
ratio of the velocity of the wind on that account alfo 
that is, the load continuing the fame, the turns of the 
fails in a given time will be as the fquare of the ve- 
locity of the wind ; and the effect, being in this cafe 
as the turns of the fails, will be as the fquare of the 
velocity of the wind alfo $ but this muft be under- 
flood only of the firft increments of the velocity of 
the wind : for, 
2dly, As the fails will never acquire above a given 
velocity in relation to the wind, tho’ the load was 
diminifhed to nothing 5 when the load continues the 
fame 
- v 
