HAVING looked a little at the great rolling ocean as a whole, suppose we venture, of course only in imagination, into its dark, deep waters. As you have stood on the ocean's shore, or sailed over its vast surface, you will often have wondered what there was, living or not living, in that vast deep; and how the living did live; and what that was like that had no life. Of course, in the deepest part there is a bottom. What is that bottom? You say rocks, stones, or sand, and they are dead enough. But if dead, let me tell you they are the bones, as it were, or at least the remains, of myriads of once-living creatures; and that the very rocks, and even mountains, that are covered up in the ocean, have been built up by these myriads of insects.
In October's number of Child's Bible Companion, 1878, you had an account of the coral island, the work of those wonderful ocean builders called the polypi, and the amazing part they have played in the construction of the whole surface of the earth. They are the smallest of God's creatures, and yet used by Him to build up the crust of the world. Only the microscope brought them to light. The coral is hard as rock; but down at the ocean's bottom we find another substance, beauty fully soft, as little like an insect as the polypi, but as surely one. This is the sponge, which we have used from our infancy.
The sponge, like the polypi, is always attached to some other substance, from which it never separates, and is found at the bottom of the sea. How do they live and grow?
They receive their nourishment from the wave which washes past them; they draw in and cast out streams of water all their lives. They cannot possibly go after their food, but God takes care that their food is brought to them. Other animals move from place to place; fishes swim in the water, animals and insects move on the land, and birds fly in the air. Not so the sponge. The seed or egg is cast off by the parent plant, floats about in search of a home, fixes itself to some rock or even shell, grows to a great size, propagates other sponges, and then dies.
Each of my readers has used a sponge hundreds of times; how little have you thought of its wonderful history. Once it was such a tiny seed or egg, that you could not possibly have seen it without a powerful magnifying-glass. If you could have watched it, you would have seen it driven, about by the waves till it touched some-substance, and it fixed itself there, never to move again till it died, or was fished up by some sponge hunter.
I need not tell you what a sponge is like. While there is a great variety, some 300 different kinds, they are all alike in this-they hold plenty of water, they are full of very small holes, and there are some holes very much larger than others. As to the construction of these finer and larger holes, and their relation one to another, their wonderful mechanism, their almost infinite variety, a big volume might be written about them. All I can now tell you is, that their one object is constantly to suck in, and then throw out currents of water. It is by these currents of water that the little; living creatures, for one sponge is made up of a whole colony, receive their nourishment, grow up, and then propagate their kind.
The above engraving shows you this operation. The immense number of small holes draws in the water, which passes through every part of the substance. From these currents its food, and that which is needful to its growth, is taken up, and having obtained all it needs from the water, it is all accumulated, and then cast out by these large cells.
Fishes live partly in the same way. Water constantly passes through their mouth and out at their gills, from which much of their nourishment is drawn.
I have told you that the sponge is really an animal, but its kind of life is wonderfully simple when compared with higher animals. There is no blood, no intricate mechanism of heart or arteries; no brain, no nerves, nothing of this kind. There is, as we have seen, circulation, by which nutriment is secured. There is no skin, no apparent provision for perspiration, as in other animals; no stomach, and yet digestion goes on, food is taken up, and refuse or waste matter is cast out.
I must say one word about the way in which sponges are reproduced. It is much after the manner of plants, which, you know, is by cuttings, grafting, and by seeds. There is a kind of sponge which, if a piece is torn off, it will maintain its independent existence, and flourish as a separate sponge. This is much like plants increased by "cuttings." Again, if two sponges growing apart approach each other, they will become united, and in a short time form but one sponge, and in such a manner that no trace of their union could be found. This, to a certain extent, represents the operation of "grafting," as practiced by gardeners. There is still another process, which represents production by seeds or bulbs. The sponge throws off these in autumn. They remain inactive during the winter, but as spring approaches, the seed-like bodies show signs of life, settle down, and become separate sponges.
In other cases positive eggs are hatched within the sponge. They much resemble a hen's egg, for although destitute of a shell, yet they have a substance which resembles a yolk, another substance which is like the white, and a delicate membrane which takes the place of a shell. Not only so, but those who have narrowly watched the process, say that the growth of the sponge-egg is very similar to that of the chick in the egg.
How wonderful are all the works of God! and the least of His creatures seem even more marvelous than the greatest.
When even the youngest of my readers next plays with his big bath sponge, he will not forget what a strange history it has had, and that once it was a living creature—one of the wonders of the deep.
I must now tell you a little about the way in which sponges are obtained.
At the present time sponge-fishing takes place principally in the Grecian Archipelago and the Syrian seas. The Greeks and Syrians sell the product of their fishing to the western nations, and the trade has been immensely extended in recent times, the sponge having become an almost necessary adjunct of the toilet as well as of the stable.
Fishing usually commences towards the beginning of June on the coast of Syria, and finishes at the end of October. But the months of July or August are peculiarly favorable to the sponge interest, if we may use the term. Latakia furnishes about ten boats to the fishery, Batroun twenty, Tripoli twenty-five to thirty, Kalki fifty, Simi about 170 to 180, and Kalminos more than 200.
The operations of one of these boats fishing for sponges on the Syrian coast is represented in our engraving. The boat's crew consists of four or five men, who scatter themselves along the coast for two or three miles in search of sponges under the cliffs and ledges of rock. Sponges of inferior quality are gathered in shallow waters. The finer kinds are found only at a depth of from twenty to thirty fathoms. The first are fished for with three-toothed harpoons, by the aid of which they are torn from their native rock; but not without deteriorating them more or less. The finer kinds of sponges, on the other hand, are collected by divers; aided by a knife, they are carefully detached. Thus, the price of a sponge brought up by diving is much more considerable than that of a harpooned sponge. Among divers, those of Kalminos and of Psara are particularly renowned. They will descend to the depth of twenty-five fathoms, remain down a shorter time than the Syrian divers, and yet bring up a more abundant harvest. The fishing of the Archipelago furnishes few fine sponges to commerce, but a great quantity of very common ones. The Syrian fisheries furnish many of the finer kinds, which find a ready market in France; they are of medium size. On the other hand, those which are furnished from the Barbary coast are of great dimensions, of a. very fine tissue, and much sought for in England.
Sponge-fishing is carried on at various other stations in the Mediterranean, but without any intelligent direction, and in consequence it is effected without any preserving foresight. At the same time, however, the trade in this product goes on yearly increasing. But it is only a question of time when the trade shall cease, the demand which every year clears the submarine fields of these sponges causing such destruction that their reproduction will soon cease to be adequate.