THE IMPROVEMENT OF RIVERS. 



SIZES OF HORSES. 



Frame of Wicket. The uprights of the wicket AC (Fig. 20) are subject to a 



bending moment, the maximum of which occurs at the point 

 of support at B, BA acting as a cantilever. BC is usually 

 made of the same dimensions as required at B ; hence, if the 

 part AB is made strong enough to support the maximum 

 moment, BC will possess sufficient strength also. 



Let U represent the water pressure on AB, n the dis- 

 tance in feet of its center of pressure from B, m the vertical 

 distance between A and B in feet, and the other letters 

 as assumed in the preceding calculations. Then 



U = wm sec a X 62$ Ibs. X ( ~ + d\. 



The distance , which may be found as shown for the 

 distance k on page 235, is 



m (m + sd) sec a 



3 (m + ad) ~ 



FIG. ao. 



The total bending moment at B, in inch-pounds, is therefore 



-IX 12. 



The sections required can then be found, as shown in the calculations for needles, 

 by the usual formulas, 



c Me . bt 3 



S - f- and / - 



