Page:Small-boat sailing; an explanation of the management of small yachts, half-decked and open sailing-boats of various rigs; sailing on sea and on river; cruising, etc (IA smallboatsailing01knig).pdf/41

 excessive weather helm—for the latter makes it necessary to keep the rudder over to leeward at a sharp angle, thus offering great resistance to the water and checking the boat's speed.

A boat carries weather helm when the centre of lateral resistance is further forward than the centre of effort of the sails.

A boat carries lee helm when the centre of lateral resistance is further aft than the centre of effort of the sails.

Thus to reduce weather helm we can either move the centre of lateral resistance further aft or the centre of effort of the sails further forward. By shifting the ballast so as to lighten the vessel forward, and make her heavier aft, we increase the submerged area of her after section, and so move back the centre of lateral resistance. By shortening her after canvas, as by taking in her mizzen, or by increasing her head canvas, as by setting a larger jib, the centre of the effort of the sails is moved forward.

Again, if it be found that a boat carry lee helm under canvas, it shows that either her ballast must be shifted forward, or that the area of her head canvas must be reduced.

ACTION OF THE RUDDER

The action of the rudder is not difficult to understand. By its aid the sailor can steer his vessel in the required direction, and if she carry—as she