| 301 | 302 | 303 | 304 | 305 |
| 1 | 306 | 613 | 919 | 1225 |
|
The proportions of light and shade in a leaf (423-426).
4
23.
OF THE SHADOWS OF A LEAF.
Sometimes a leaf has three accidents [of light] that is: shade,
lustre [reflected light] and transparency [transmitted light]. Thus,
if the light were at n as regards the leaf s, and the eye at
m, it would see a in full light, b in shadow and c
transparent.
4
24.
A leaf with a concave surface seen from the under side and
up-side-down will sometimes show itself as half in shade, and half
transparent. Thus, if o p is the leaf and the light m and the
eye n, this will see o in shadow because the light does not fall
upon it between equal angles, neither on the upper nor the under
side, and p is lighted on the upper side and the light is
transmitted to its under side. [Footnote: See Pl. XXVIII, No. 2, the
upper sketch on the page. In the original they are drawn in red
chalk.]
4
25.
303
Page
Quick Jump
|