202

On the relative depth of cast shadows.

The shadow cast by an object on a plane will be smaller in proportion as that object is lighted by feebler rays. Let d e be the object and d c the plane surface; the number of times that d e will go into f g gives the proportion of light at f h to d c. The ray of light will be weaker in proportion to its distance from the hole through which it falls.

FIFTH BOOK ON LIGHT AND SHADE.

Taken from The Notebooks of Leonardo da Vinci edited by Jean Paul Richter, 1880.

Notebooks of Leonoardo da Vinci

III: Six books on Light and Shade.

. . .

The effect of light at different distances.

Further complications in the derived shadows.

183,

184,

185,

186,

On the shape of the cast shadows.

188,

189,

190,

On the outlines of cast shadows.

192,

193,

194,

On the relative size of shadows.

196,

Effects on cast shadows by the tone of the back ground.

A disputed proposition.

On the relative depth of cast shadows.

200,

201,

Principles of reflection.

203,

On reverberation.

Reflection on water.

206,

Experiments with the mirror.

208,

209,

Appendix:--On shadows in movement.

211,

The effect of rays passing through holes.

213,

On gradation of shadows.

On relative proportion of light and shadows.

216,

217,

218,

219,

220,

. . .