PNEUMATICS. 



centre, to 9 at its extremity. SMEATON made 

 some corrections on this rule, from experiment. See 

 Experimental Inquiry concerning Mills, p. 45, and 



370, From SMEATON'S experiments it appears, 

 that a windmill works to the greatest advantage, 

 when it is so constructed that the velocity of the 

 sails, is to their velocity when they go round with- 

 out any load, as 6.5 to 10 nearly; and also that, 

 the load, when the mill works in this manner, is to 

 the load that would just keep it from moving, as 

 8.5 to 10 nearly. 



Experimental Inquiry, p> 49 and 50. 



371. With different velocities of wind, the load 

 that gives the maximum effect, varies nearly as the 

 square of the velocity of the wind, and the effect 

 itself nearly as the cube. 



Ibid. p. 52. 



The effect is always measured by the product of the 

 velocity of the load into its weight. The velocity 

 of the load varies in the simple and direct ratio of 

 the velocity of the wind. 



Resistance 



