Reinforcing the Cloth.

While not absolutely necessary for amateur purposes,
reinforcement of the cloth, so as to avoid any tendency
to split or tear out from wind-pressure, is desirable. One
way of doing this is to tack narrow strips of some
heavier material, like felt, over the cloth where it laps
on the ribs. Another is to sew slips or pockets in the
cloth itself and let the ribs run through them. Still another
method is to sew 2-inch strips (of the same material
as the cover) on the cloth, placing them about one
yard apart, but having them come in the center of each
piece of covering, and not on the laps where the various
pieces are joined.

Use of Armpieces.

Should armpieces be desired, aside from those afforded
by the center struts, take two pieces of spruce, 3 feet
long, by 1 x 1 3/4 inches, and bolt them to the front and
rear beams of the lower plane about 14 inches apart.
These will be more comfortable than using the struts,
as the operator will not have to spread his arms so
much. In using the struts the operator, as a rule, takes
hold of them with his hands, while with the armpieces,
as the name implies, he places his arms over them, one
of the strips coming under each armpit.

Frequently somebody asks why the ribs should be
curved. The answer is easy. The curvature tends to