EXPERIMENTS OF FIXING THE PADDLE-BOARDS, &c. 57 



These experiments also very satisfactorily confirm the preceding calculations of the lost power 

 with different immersions of the radiating wheel. The effective power in the calculated table with 

 the immersion '252 of the radius is 660, and with the immersion -550 of the radius it is 553. In 

 the experiments with immersion '123 of diameter or '246 of radius, the effect is 9086, (radi- 

 ating wheel, No. II.); and with immersion -273 of diameter or -540 of radius, the effect is 

 7466, which will be found to have nearly the same ratio as the two calculated numbers ; and 

 the same will hold good with all the experiments in the table. 



EXPERIMENTS TO ASCERTAIN THE EFFECT OF FIXING THE PADDLE-BOARDS 

 AT AN ANGLE WITH THE RADIUS OF THE WHEEL. 



In the radiating wheel as commonly constructed, the arms radiate to the centre, and the 

 floats being attached to the faces of them, make an angle with the true radius, which has 

 the effect of causing the paddles to enter the water more obliquely, and thereby in- 

 creasing the concussion. To obviate this, Messrs. Maudslay and Field have constructed 

 wheels, so that the arms radiate to points at such a distance from the centre, that the faces 

 of the floats are in the true line of the radius, which is found to have a beneficial effect. 



The object of the following experiments was to ascertain how far an advantage would be 

 gained by giving the floats an angle in a contrary direction, (viz. so that they radiate when 

 entering the water to a point forward of the centre of the wheel,) and thereby causing them 

 to enter less obliquely. 



The experiments were made with the same apparatus as the preceding ; and they were 

 repeated in some immersions with the wheel inverted, so that the motion was in a contrary 

 direction, to represent the effect of angling the paddles aft of the centre. The remaining four 

 columns of each division of the table represent, 1st, The number of circuits or revolutions 

 made in the reservoir ; 2nd, The time of the experiment in seconds ; 3rd, The relative 

 velocity obtained by dividing the circuits by the time ; and 4th, The useful effect cal- 

 culated, as we have before described, by multiplying the square of the velocity by the 

 circuits, which is doubled for the double area. 



