36o CALCULATIONS for 



/ being 6 feconch, 8^' s^ 7^ = 3. 325 cubic feet and § 7/^= 10.64 

 feet, tiie uniform velocity in one fecond j alfo haw = 34.57 lbs. 

 the force of impact on the wheel. 



For two pair of (tones, /j being = 1.75 and a = 0.417. 

 8aqVh=2y gallons in 1" and 8aqt V /j= 162 gallons in 6 feconds. 

 8rt\//j = 4.4 cubic feet, S^ h= 10.584 and bazu = 46.5 pounds. 



Keyger's faw-mill with a 4 feet head =h and a = 0.0833. 

 Saq V /j = S.2 and SagtV /j=4g.2 gallons in 6 feconds. 

 SaV /} = i.2^ cubic feet, 8 V/j= 16 feet the uniform velocity in i"j 

 alfo haiu = 20.8 lbs. the force of impaft. 



The fame mill with a 6 feet head = h and a = o. 167. 

 Sag ^/j = 20, 8aqt ^/b= 120, 8a y/Z) = 3.273, 8 ^h= 19.6 

 and haw = 62.6 pounds. 



If it be intended that the receiver fhall contain 122.28 gallons 

 for one pair of ftones, and 162 gallons for two pair, we fhall 

 find that the former number is equal to a cylinder 4 feet high by 

 30 inches diameter, and that latter number is equal to one of 

 the fame height by 3 feet diameter ; but to find the area of the 

 gateway in the penftock, adapted to the fleam-engine, which is 

 4 feet deep inftead of 22 inches, we mufl; find an area .v for the 

 aperture, which fnall difcharge as much water in a given time, 

 (which we will fuppofe to be 6 feconds) as flows through the 

 gateway of Beydler's mill in the fame time ; making therefore 

 H = the head of water at. the fteam-engine, and h = that of 

 the grift-mill j alfo a = the gateway as before, we have .v^/H 



= rty/Z), and A* = _i_— = 0.2078 for one pair of ftones, and 



y/H 



0.2758 for two pair. Now llx?t being to /jaw nearly in the 

 ratio of 3 to 2 for the difference of the forces of impaft, we 

 may fafely conclude that receivers of the above dimenfions will 

 be amply fufficient for fupplying the water-wheel with a power 

 as much fuperior to Beydler's mill, as the difference between the 

 forces of impaft will amount to. 



With refpeft to Keyger's faw-mill we fliall only remark, that 

 as the quantity of water pafTmg over the wheel with a 6 feet 

 liead, is fo nearly equal to that which Beydler's mill requires for 

 one pair of ftones, that a receiver of equal dimenfions will be 

 found fufiiciently large, the penftock of the fteam-engine being 

 alfo 6 feet deep. 



It 



