Weighing by Percussion Along a Hinged Arm
How the striking point (a, b, c, d) changes the effect on a 100-lb load
The diagram shows a horizontal beam crossed by a raised, hinged arm that can swing to strike downward, with a vertical post and a small box marked 100 resting on a platform. Leonardo proposes a method of weighing that examines percussion: what difference it makes to strike at points d, c, b or a along the arm, and asks that the differences and their causes be noted.
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The effect of percussion at points a, b, c, d
Leonardo calls this a method of weighing and asks what difference the percussion makes when the blow is delivered at d, at c, at b, or at a. He instructs that the differences and their causes be recorded.
Hinged striking arm over a 100-unit box
An inclined arm pivots above a horizontal beam and can fall to strike; a vertical post supports it, and a small box marked 100 sits at the right on a platform. The apparatus tests how the point of impact bears on the marked load.