Water in a bucket, shadows from many lights, and the blow of a hammer

Why water splashes higher in a bucket than in a lake

Struck water in a bucket cannot dissipate its motion from ring to ring as it would in a great pool, and the hard, resistant walls prevent it from spreading in many waves. So its whole flight turns upward, and the water struck by a stone or drop leaps higher when confined than when open.

Two lights of equal size and distance

If the light x v is equal to the light v y, the variation of the lights will be as much as their size. The left-hand figure sets a large and a small light equidistant from the centre to compare the shadows they cast.

Shadow-darkness follows the distance between the lights

The darkness of shadow a b to shadow b c holds the same proportion as the distance of the lights n m to m f. Because a b is nearer to light n than b c is to light f, a b is lighter by as much as it is nearer its light, the two lights being of equal power.

A body between two lights casts two opposite shadows

If a shadowy body is set at equal distance between two lights, it makes two opposite shadows, differing in darkness as much as the powers of the two opposing lights differ. If the two lights are of equal size and equally remote, the two derivative shadows are of equal darkness.

The blow drives the nail before the hammer yields

Because the blow is the swiftest and most powerful thing men can make, the nail, receiving that force on its head, has already penetrated and obeyed the blow before the opposing hammer has yielded; for this the nail makes good passage.

When a nail twists or bends under the blow

When the force of the striking weight overpowers the nail's resistance and the wood resists its passage, the nail twists under the blow instead of driving in. And when the blow does not travel along the line of the nail, the nail bends and does not enter.

A sinistra. Figura di lume grande e lume piccolo equidistanti dal centro, con:

A destra, figura analoga, lumi non equidistanti:

Figura analoga, due lumi uguali, con:

A destra.

Due lumi uguali equidistanti dall'ombroso:

Lungo il margine destro. Accetta che infigge un cuneo.

Accetta che spacca un massello.

Accetta che stacca una parte dal massello:

Martello che batte un chiodo in un asse. Martello opposto:

Figura analoga col chiodo contorto:

Figura analoga col chiodo piegato:

Figura di due luminosi equidistanti all'ombroso, con:

Tre luminosi equidistanti all'ombroso, con:

Luminoso maggiore dell'ombroso, con:

Water.

On the left. Figure of a large light and a small light equidistant from the centre, with:

On the right, analogous figure, lights not equidistant:

Analogous figure, two equal lights, with:

On the right.

Two equal lights equidistant from the shadowy body:

Along the right margin. A hatchet driving in a wedge.

A hatchet splitting a block.

A hatchet detaching a part from the block:

A hammer striking a nail into a board. Opposed hammer:

Analogous figure with the twisted nail:

Analogous figure with the bent nail:

Figure of two luminous bodies equidistant from the shadowy one, with:

Three luminous bodies equidistant from the shadowy one, with:

A luminous body larger than the shadowy one, with: