The engineer's sketch-book of mechanical movements, devices, appliances, contrivances and details employed in the design and construction of machinery for every purpose

by Thomas Walter Barber

[719]. Multiple trammel gear. The pinion is half the diameter of the wheel, and makes two revolutions to one of the wheel.

[720]. Trammel crank gear; the crank revolves once to two double strokes of the rod.

[721]. Knight’s noiseless gearing, for two shafts running in opposite directions. Each shaft has two equal cranks at right angles, which are coupled by links to rocking arms, which are also coupled in pairs.

[722]. Eccentric variable speed toothed gear.

[723]. Scroll bevil gear.

[724]. Segment reversing gear, to obtain two speeds in portions of one revolution, and in opposite directions. See Reversing Gear, [Section 74].

[725]. Snail wheel, or scroll ratchet.

[726]. Combined spur and bevil wheel.

[727]. Double screw gear, for steering gear, &c.

[728]. Angular ball-jointed crank motion.