Balances, the centre of the world, waves and crossbow range
Statics of the balance and the seat of gravity; waves washing an oblique shore; measuring a crossbow's true range
The left folio carries balance and lever diagrams accompanied by notes on how a balance loses its potential arms as it nears the centre of the world, and how the seat of gravity is distributed along the whole length of a body's support. The right folio studies the sea: waves striking an oblique shore lose depth and rework the sand as they advance and retreat. Other notes explain that a crossbow's true range can only be gauged from a high vantage, and a fragmentary caption describes an upper basin emptying and filling. Extensive further mirror-script text on the sheet is not part of the transcription.
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A balance near the centre of the world
Leonardo states that one and the same balance diminishes its potential arms the more it approaches the centre of the world. He adds a parallel observation that air becomes more rarefied the closer it draws to the heat that warms it.
The seat of gravity along a support
The seat of gravity is said to lie not in the heavy body but throughout the whole length of its support, and entire in every part of that length. Placing the centre of the world at s and a uniform frame n m o p, Leonardo hangs equal weights c and d at a and b, then lengthens the pendant s d beyond a c to argue that the weights are no longer equidistant from the centre by their bodies, though they remain so by their weights.
Waves and sand on an oblique shore
A wave meeting an oblique shore always loses depth, and the width of a shore's sandy stretches depends on how closely spaced the incoming waves are. The retreating wave washes sand back and, colliding with the next wave, is thrown back with its load, so the sand does not spread into the second wave. The advancing wave is undercut by the water returning from the shore and is clouded by the sand stolen from the wave before it.
Finding the true range of a crossbow
Leonardo notes that it is impossible to know a crossbow's true range unless one releases it from a high place. The construction a b c is offered as the true method of measuring that range, since it cannot be known where the arrow does not fall in a straight line and stay fixed in that same direction.
An upper basin emptying and filling
A fragmentary caption beside a lettered figure describes an upper vessel emptying while another fills, and a ladder or stepped device that does not pour. The passage is broken and only partly legible in the transcription.