Why an Oblique Shot Fails to Pierce a Wall
Ball and burst-chamber sketches with a 60-degree protractor for gauging impact angle
This crowded sheet mixes drawings and geometry to study the angle at which a projectile strikes a wall. At the top are two figures of a ball and a labelled 'burst chamber', while the left column poses the physical question of why a ball fired obliquely at a wall does not drive through it as a straight shot does. The lower half is dominated by a fan-shaped protractor and a circular sector divided into 60 degrees, whose lettered points set the first and last degree of obliquity for measuring the impact angle. A smaller analogous figure and quarter-sector appear at the right.
On this page
Why an oblique ball does not pierce like a straight one
Under the theme of striker, impact and struck, Leonardo asks why a ball fired obliquely at the wall does not make a passage through it as one fired straight across does. This frames the whole page's inquiry into how impact angle governs penetration.
A circular sector divided into 60 degrees of obliquity
A sector of a circle a b - c is divided into 60 degrees. Within the tangency of the perpendicular a c the first degree of obliquity begins and the last one ends, giving a scale against which the slant of the shot can be read.
Lettered diagram for the projectile's angle of impact
A large lettered diagram for measuring the projectile's angle of impact carries the points a l - m n o p q r - b c - d e f g h i k, set in the tangency of the level line a b. Rays fan out from a central point to the graduated arc.
Studies of a shot and a burst-chamber
The top of the sheet carries two figures of a ball together with a labelled 'burst chamber' shown as a horizontal device with a spoked wheel. These artillery components fix the practical context of the impact-angle study that fills the rest of the page.