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Colours reflected. Thickness in thousandth
parts of an inch. Names of the Colours, or
substances having them. In air. In water. In glass. 1st Order. Very black 1/2 3/8 10/31 Black 1 3/4 20/31 Beginning of black 2 11/2 12/7 Blue 22/5 14/5 111/20 Whitish sky-blue. White 51/4 37/8 32/5 Tarnished silver. Yellow 71/9 51/3 43/5 Straw colour. Orange 8 6 51/6 Dried orange-peel. Red 9 63/4 54/5 Geranium Sanguineum. 2nd Order. —————— —————— —————— ———————————— Violet 111/6 83/8 71/5 Iodine. Indigo 125/6 95/8 82/11 Indigo. Blue 14 101/2 9 Cobalt blue. Green 151/8 111/3 95/7 Water, aquamarine. Yellow 162/7 121/5 102/5 Lemon. Orange 172/9 13 111/9 Orange. Bright red 181/5 133/4 115/6 Bright May-pink. Scarlet 192/3 143/4 122/3 3rd Order. —————— —————— —————— ———————————— Purple 21 153/4 1311/20 Flax-blossom. Indigo 221/10 164/7 141/4 Indigo. Blue 232/5 1711/20 151/10 Prussian blue. Green 251/5 189/10 161/4 Bright meadow green. Yellow 271/7 201/3 171/2 White wood. Red 29 213/4 185/7 Rose. Bluish red 32 24 202/3 4th Order. —————— —————— —————— ———————————— Bluish green 34 251/2 22 Green 352/7 261/2 223/4 Emerald. Yellowish green 36 27 232/9 Red 401/3 301/4 26 Pale pink. 5th Order. —————— —————— —————— ———————————— Greenish blue 46 341/2 292/3 Sea-green. Red 521/2 393/8 34 Pale pink. 6th Order. —————— —————— —————— ———————————— Greenish blue 583/4 44 38 Light sea-green. Red 65 483/4 42 Paler red. 7th Order. —————— —————— —————— ———————————— Greenish blue 71 531/4 454/5 Very faint. Ruddy white 77 573/4 492/3 Ditto.