Blow. I say that the blow is the terminus of a rapid motion made by bodies into resistant objects. This same thing is the cause of all sounds; it is what breaks and transmutes various things, and what causes secondary motion anew. Nothing is briefer or of greater power, and it proceeds to diversify itself according to its causes. — The blow is the terminus of a rapid motion caused by force and carried out by weight into an object; it produces sounds, which transmute its effects. Nothing is of briefer operation, nor of greater power. Its result is the greatest velocity and penetration into every variety of object placed before it; it leaves its point of origin in circular movement, and it is wholly and entire in every part. — The blow is the terminus of a rapid motion caused by force and carried out by bodies into resistant objects. From this derive the sounds, from this the breakage; and nothing is of briefer operation, nor of greater power. Its result is of the greatest velocity and penetration into any variety of object placed before it.

If the water descends one finger per mile and moves forward at one mile per hour, how far forward will it move in descending two fingers?

The parts of a stone moved by force and hurled against the earth will have a longer and faster course, and make greater clamor, than the former; [the following line was then canceled with a small diagonal stroke of the pen:] because these parts make circular movement after their percussion.

On motion. Motion is caused by force and applied to bodies that are displaced from their places. It becomes rapid through quick and powerful causes; slow causes make its course brief. It does not come to an end without doing violence to whatever opposes it.