'244 



OF THE PARTS OF 



[SECT. vn. 



512. The teeth of wheels will be most conveniently given in a tabular form, 

 with a correction for curvature in determining their breadth, which is not in- 

 cluded in the formula in my treatise on cast iron. The first column shows the 

 stress on the teeth in Ibs. ; the second, the horse power nearly equivalent, 

 when the velocity is three feet per second ; the third column, the pitch ; the fourth, 

 the thickness ; and the fifth, the breadth of the teeth : the sixth column shows the 

 greatest depth of the middle of the arm at the base in the direction of the wheels' 

 motion, when that part is one-third of the breadth of the teeth, and the radius is 

 one foot ; hence, being multiplied by the square root of any other radius in feet, 

 it will be the depth for it ; the seventh column shows the breadth of the rib which 

 strengthens the arm ; and the eighth, the diameter of a cylinder, when the force 

 of the steam is thirty-five inches of mercury in the boiler, and the teeth move at 

 the same velocity as the piston. For any other velocity the stress will be found 

 by art. 500. 



513. A TABLE OF THE STRENGTH, &c. OF TEETH AND ARMS 



FOR WHEEL WORK. 



