OCR
Absorption of light, selective, 66, $3, 100, note. Aitken, Dr. John, on the colour of water, 82. Avebury, Lord, on the colour of water, 85. Bidwell, Dr. Shelford, on " afterimages,” 108, note. Blackness of deep water, 67. Channel, English, 77, 102. Church, Prof. A. H., on the mixture of colours, ror, note. Cloud reflexions in rippled water, 47, 48, 104. Cloud shadows, 78, 104, 107, IIo. Colour of water, apparent. See ‘“* Local colour.” Colour of pure water, 67, note, 83, 86. Colour of water, greenish: due to vegetable stain, 67, note, 85, 86, 88; to mineral impregnations, 87; to colour of bottom or of suspended particles, 67, 83, 97, 103. Colour of deep water, purplish, 96. water, 82, 99, 106, Colours, complementary, ror, note. , Contrast, effects of, 107, 110. Cornwall, 102. | Currents causing differences of colour, 90, 102. Curve, caustic, 62, note; harmonic, or curve of sines, 31, note. Davy, Sir Humphry, on the colour of water, 85. Depth of water, apparent, 62, | | note. Engadine lakes, 69, 94. Forel, experiments on colour of water, 85. Glass, coloured, experiments with, 66, 73, 79Glass, greased, reflexion of candle flame in, 41. Horizon, 98. Horizontal lines of image, dis| appearance of, in rippled water, 44, 48, 52. Ice, colour of, 69, note, 88. . Ice, reflexions in rough, 50, I