[729]. Crank gearing between two shafts running in the same direction. See [No. 187]. The cranks should be similar to [Nos. 174] or [175].

[730]. Snail worm gear.

[731]. Diagonal engine or pump, with bevil gear revolving motion and three or more cylinders.

[732]. Angle coupling on Dr. Hooke’s principle. See [No. 292].

[733]. Worm and crown gear. Used in chaff machines; useful to obtain a slow feed on two shafts in opposite directions.

[Larger plate.]

[734]. Ball wheel, with limited angular traverse gearing into one or two pinions.

[735]. Scroll and rack.

[736]. Variable speed gear, from an elliptical or other irregular-shaped driving wheel, combined with a tied idle intermediate wheel.