Stranica 180 [180]
II4
Image, virtual, formed by reflex¬
ion in a plane mirror, 7.
Images of a point in rippled water,
36.
“Local colour,” brilliancy of:
dependent on illumination, 68,
76, 78, 97; On proportion of
suspended particles, 68, 83,
102; on reflective power of
bottom, 70, note, 102 ; on angle
of vision, 72, 75, note, 81; in
reflexions of dark objects, 78,
79, note, 82, 95, 104; increased
by ripple, gr.
Maxwell’s colour-discs, roo, note.
Mediterranean, 83, 84, 96.
Mirrors, tilted to represent wave
surfaces, 26.
Mixture of colours, 100.
Painting of reflexions in rippled
water, 51.
Particles, suspended, 67, 68, 83,
97:
Pigments, mixture of, 100.
Purple caused by mingling of
tones in rippled water, 82, 99.
Purple colour of shadows on snow,
108; on water, 107, IIOo.
Purple colour of deep water, 96.
Purple patches due to seaweed,
98.
Rain falling on still water, 50.
Rainbow, reflexion of, 21.
Reflective power of water, 64,
note,
Reflexion, law of, 5.
Reflexion, irregular, 9, 107.
Reflexion, total internal, 61, note.
‘* Reflexion,” the observer’s view
of the image, ro.
Reflexions, perspective of, 18.
Reflexions, elongated, 34 ef seg. ;
perspective of ditto, 56; ditto
inclined, 43; distorted, 55.
Refraction, 61, 81.
9 Rings,” 52.
Ripple interrupting the image, 31,
95.
Ripple elongating the image, 34,
44, 50.
Ripple reflecting light from differ¬
ent parts of sky, 89, 98, 99,
106.
Ripple showing local colour, 91
él Seq.
Rood, Prof. Ogden, tor, 108,
note.
Ruskin, quoted, 17, 21, 48, 59,
80.
Sand, wet, reflexions in, 73, 106,
107.
Sandy bottom, 70, note, 98, 103.
Sea-water, colour of: Aitken on,
$3; Davy on, 88; Threlfall on,
S4.
Seaweed, 85; purple patches
caused by, 98, rio.
Shade and shadow, 109.
Shadows on water, 77, 81, 104,
107, I10; on snow, 107.
Sky, extent of, reflected in rippled
water, 47, 89, 98, 106.
“Streaks,” vertical, 36 ez seg., 104;