Motion through air, the blow, and the noise of the bombard
Why pointed bodies fly farther, why loud blows do least harm, and where a cannon's sound is made.
A dense sheet of propositions on moving bodies, impact and sound. Leonardo observes that a body meeting less resistance in air travels farther, a long acute pyramid-shaped body outdistancing a round one of equal weight, and that a faster driving cause carries a projectile farther. On the 'blow' he notes that the loudest impact does the least harm (a sword struck flat is noisy but harmless, struck edgewise quiet but cutting) and that a yielding target is spared while a resisting one is damaged, as a treetop bends from the ax but is severed on a stump. He closes with questions on the origin of noise, asking whether a bombard's report is made in its tube, at its mouth, or in the percussion of fire against the air. Two small forms labeled 'iron', one round and one long and finned, illustrate the contrasted moving bodies.
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Pointed bodies travel farther than round ones
The less resistance a thing meets moving through air, the farther it goes; a long, acute body of pyramidal proportions travels farther than a round body of equal weight. Two small drawings labeled 'iron', one round and one long and finned, illustrate the two forms.
A faster cause drives a body farther
The faster the cause that moves, the farther it drives the thing moved; a medium speed, however vigorous, drives its weight the same distance a weak but rapid force drives its proportional weight.
The loudest blow does the least harm
For a blow of equal weight, motion and force, the one making the louder report does less harm. A sword struck flat on a table is noisy but does little damage; struck edgewise it is quiet but cuts deeply.
A resisting target is damaged; a yielding one spared
A thing that resists a blow is more damaged, for if it moves when struck it follows the striker and is unharmed. Treetops bend from the ax and are spared, but severed on a stump; the sickle cuts grasses at their bases, not their tops.
A small weight from high strikes like a medium one lower
A small weight falling from high up will damage its object as much as a medium weight falling from lower down.
Where is a bombard's noise made?
Leonardo asks whether the noise of a bombard is made in the tube, at the mouth, or in the percussion the fire makes against the air; and he holds that a rarefied body (the fire) striking and rebounding against the air makes the report.