Page:Physical Geography of the Sea and its Meteorology.djvu/289

Rh with the microscope, lie finds in the surface water alongside; and though he has been following the sea for many years, he never fails to express his wonder and amazement at the immense numbers of living creatures that the microscope reveals to him in sea water. Hitherto his examinations related only to the surface waters, but in the log now before me he went into the depths, and he was more amazed than ever to see how abundantly the waters even there bring forth. "January 28th, 1855.—In examining animalculæ in sea water, I have," says he, "heretofore used surface water. This afternoon, after pumping for some time from the stern pump seven feet below the surface, I examined the water, and was surprised to find that the fluid was literally alive with animated matter, embracing beautiful varieties." Of some he says, "Numerous heads, purple, red, and variegated." There is wonderful meaning in that word, as it stands recorded in that Book, and as it is even at this day repeated by the great waters, a striking instance of which has been furnished by Piazzi Smyth, the Astronomer Royal of Edinburgh, during his voyage in 1856, on an astronomical expedition to Teneriffe. On that occasion he fell in with the annual harvest of medusæ (§ 160) that are sent by the Gulf Stream to feed the whales. His description of them (§ 161) has already been quoted. According to the computation made by him, it appears that each one of these sea-nettles, as they are sometimes called, had in his stomachs not less than five or six millions of flinty shells, the materials for which their builders had collected from the silicious matter which the rains washed out from the mountains, and which the rivers bring down to the sea. The medusæ have the power of sucking in the sea water slowly, drop by drop, at one end, and of ejecting it at the other. From this they derive both food and locomotion; for in the passage of the water, they strain it, and collect the little diatomes. Imagine, then, how many drops of water in the sea, which, though loaded with diatomes, never pass through the stomach of the medusæ. Imagine how many the whale must gulp down with every mouthful of medusæ. Imagine how deep and thickly the bottom of the sea must, during the process of ages, have become covered with the flinty shells of these little creatures. And then recollect the command which was given to the waters of the sea on the fifth day, and we may form some idea of how literally they have obeyed this order, bringing forth