At times it requires vigorous motion, such as takes place when an oar is dipped, a stone thrown, or paddle-wheels dashed into the water; but at other times, the mere motion of the ocean swell, even in calm weather, is sufficient to stir up the lambent light and cause the crest of every undulation to glitter as if tipped with burnished silver. In such circumstances we have seen the ends of the oars of a boat silvered with it when lifted out of the wave, and the drops which fell from them before being redipped resembled the most beautiful diamonds.
Mr. P. H. Gosse, in his interesting work, “The Ocean,” gives the following account of this luminosity of the sea, as witnessed by himself on one occasion:—
“In a voyage to the Gulf of Mexico, I saw the water in those seas more splendidly luminous than I had ever observed before. It was indeed a magnificent sight, to stand on the fore-part of the vessel and watch her breasting the waves. The mass of water rolled from her bows as white as milk, studded with those innumerable sparkles of blue light. The nebulosity instantly separated into small masses, curdled like clouds of marbles, leaving the water between of its own clear blackness; the clouds soon subsided, but the sparks remained. Sometimes one of these points, of greater size and brilliancy than the rest, would suddenly burst into a small cloud of superior whiteness to the mass, and be then lost in it. The curdling of the milky appearance into clouds
