Flying-machine controls and river-barrier devices
Cranks, pedals and the 400-pound harness of the prone pilot; a gravel chest and gabions against the current
A mixed sheet joining flight to water-works. Leonardo gives details of the cranks and pedals of the flying machine and shows the prone pilot braced on a chamois skin between throat and crotch, gripping a windlass and exerting some 400 pounds of force, as quick as lashing out with kicks. Alongside are river-defence devices: a hinged chest, lettered A, for casting blocks of fine gravel and lime that are dried and sunk one atop another as a barrier against the force of the water, and gabions filled in alternating layers of gravel and brushwood.
On this page
The prone pilot on a chamois-skin harness
Under the body, between the fork of the throat and the crotch, lies a chamois skin. The pilot braces with head and feet, holds a windlass in the hands, and exerts a force of 400 pounds between feet and hands, as quick as if lashing out with kicks. Two further sketches give details of the cranks and pedals of the machine.
Cranks and pedals of the flying machine
A drawing is captioned as a detail of the cranks and pedals of the flying machine, with another detail beside it. These show the linkage the pilot works with the feet. Their construction is read only from the sketches.
A hinged chest for gravel-and-lime blocks (A)
The device A is a chest that can be opened and emptied, in which blocks of fine gravel and lime are cast and left to dry on the ground. They are then placed under water, one upon another, as a barrier against the force of the water. It stands beside a small cascade.
Gabions layered with gravel and brushwood
Gabions are filled with alternating courses: a layer of brushwood laid flat one way, then a layer of gravel, then a layer laid the other way, then gravel again. The filling continues layer by layer. Cross-hatched panels on the sheet show the woven work.