Glaucus; Or, The Wonders of the Shore

What if the water fails, after all? Then Mr. Gosse’s artificial sea-water will form a perfect substitute. You may buy the requisite salts (for there are more salts than “salt” in sea-water) from any chemist to whom Mr. Gosse has entrusted his discovery, and, according to his directions, make sea-water for yourself. One more hint before we part. If, after all, you are not going down to the sea-side this year, and have no opportunities of testing “the wonders of the shore,” you may still study Natural History in your own drawing-room, by looking a little into “the wonders of the pond.” I am not jesting; a fresh-water aquarium, though by no means as beautiful as a salt-water one, is even more easily established. A glass jar, floored with two or three inches of pond-mud (which should be covered with fine gravel to prevent the mud washing up); a specimen of each of two water-plants which you may buy now at any good shop in Covent Garden, Vallisneria spiralis (which is said to give to the Canvas-backed duck of America its peculiar richness of flavour), and Anacharis alsinastrum, that magical weed which, lately introduced from Canada among timber, has multiplied, self-sown, to so prodigious an extent, that it bid fair, a few years since, to choke the navigation not only of our canals and fen-rivers, but of the Thames itself: {206} or, in default of these, some of the more delicate pond-weeds; such as Callitriche, Potamogeton pusillum, and, best of all, perhaps, the beautiful Water-Milfoil (Myriophyllium), whose comb-like leaves are the haunts of numberless rare and curious animalcules:— these (in themselves, from the transparency of their circulation, interesting microscopic objects) for oxygen-breeding vegetables; and for animals, the pickings of any pond; a minnow or two, an eft; a few of the delicate pond-snails (unless they devour your plants too rapidly): water-beetles, of activity inconceivable, and that wondrous bug the Notonecta, who lies on his back all day, rowing about his boat-shaped body, with one long pair of oars, in search of animalcules, and the moment the lights are out, turns head over heels, rights himself, and opening a pair of handsome wings, starts to fly about the dark room in company with his friend the water-beetle, and (I suspect) catch flies; and then slips back demurely into the water with the first streak of dawn.