Swivel guns, cartridges and a spring-finned dart
Light artillery on trestle and mantlet mounts, powder charges, and chained floor beams
The sheet studies light artillery pieces (spingarde): one long-barrelled gun rests on a trestle carriage at the top, a second on a protective mantlet below. To the left Leonardo details the ammunition, including a cartridge that goes inside the ball, a breech that does not recoil so the gun may be fired from a galley, and a casing holding two grades of powder marked a and b. A dart whose fins spring outward as it leaves the barrel, and a scheme for chaining together floor beams so they will not bend, complete the page.
On this page
Spingarda on a trestle carriage
At the top a long-barrelled swivel gun (spingarda) is set on a trestle-like carriage. A second such gun below is mounted behind a mantlet, a movable shield that protects the crew.
Cartridge placed inside the ball
A drawing at left shows the propelling charge as a casing (cartoccio) meant to sit inside the projectile itself, so charge and ball are loaded together.
Breech that does not recoil
A detail of a bombard's tail shows a touch-hole and a breech designed so the piece does not run backwards when fired, allowing it to be used aboard a galley.
Cartridge with two grades of powder (a, b)
Another casing is packed with two kinds of powder: a is a soft, fine powder, while b is a soft powder of the coarser bombard type. The letters a and b label the two charges.
Dart with spring-out fins
A dart is drawn whose feathers are meant to snap outward on a spring the moment the dart leaves the spingarda, stabilising it in flight.
Chained beams that will not bend
At the foot of the sheet Leonardo shows a way of chaining or tying together the beams of a floor (palco) so that the assembled span does not sag or bend.