White ants city
"But, Uncle Philip, you said you would tell us about the soldiers and labourers coming out when the city is attacked."
"Yes, I did. As soon as a hole is made in the outside wall, you will see a soldier run out, and walk about as if to look around; but as he is blind, it cannot be to see what the danger is. He may have some way though of finding out without seeing. Presently he will go in, as if to tell the others, and then out pour the soldiers in great numbers, as fast as the hole will let them; and just as long as you strike the outside wall, they will continue to rush out. They seem to be in a terrible passion. They are in such a hurry that sometimes they slip, and roll down the outside of the hill; but they jump up again instantly, and begin to bite every thing they run against, for they are blind and cannot tell a friend from an enemy."
"Do they bite hard, Uncle Philip?"
"Very hard indeed. They make their hooked jaws, which are like awls, you know, meet at every bite; and if it should happen to be a man's leg they get hold of, you would see upon his stocking a spot of blood an inch long. At every bite too you may hear their jawssnapping together and making quite a noise. Some of them too (perhaps they are the officers) are constantly beating with their awls upon the outside wall, and make a sound something quicker and sharper than the ticking of a watch. You may hear it at a distance of three or four feet. When these biters lay hold, nothing will make them let go; you must tear them away by pieces. After you stop striking the wall, in about half an hour they seem to get over their rage and go back into the city, and then out come the labourers. While the noise continues you will not see one of them; they all fled at the first appearance of danger. But now they come, each one with a bundle of mortar in his mouth, ready made; and they stick it on the hole so fast, and with such order, that though thousands and thousands are at work they never interrupt each other. And while the labourers are busy, if you look you may commonly see a soldier or two walking about; but they never touch the mortar, nor help in any way to mend the hole. One of these soldiers always stands near the spot where the labourers are at work, and every now and then turns slowly around, and frequently lifts up his head, and with his awlsbeats upon the building, and makes a sort of hissing noise. As soon as that is done you may hear a loud hiss from all the labourers, both on the outside of the wall and from the inside of the city, and then the labourers run faster, and work as quick again. If you attack the nest again, away run all the labourers as fast as their legs will carry them, and out pour the soldiers as before; and the same thing is always seen upon every attack, of soldiers to fight and labourers to work."
"Well, Uncle Philip, this is a very strange story; much more interesting than any we have yet heard."
"I thought it would please you, boys; but there are still stranger things among animals, and perhaps you will say so when you know more.
"But it is now time to return home; so take in the kite and let us be going."
Uncle Philip tells the Children about some other Ants, that are very good Masons, and build Walls and Ceilings; and a Story about a very sensible Ant, which seemed to think a little.
"Goodmorning, good morning, Uncle Philip; we have been so much delighted with the stories about the white ants, that we hope you have more of the same kind to tell us."
"Why, as to that matter, boys, I can tell you much more about ants, for there are many kinds of them; but I am not sure that I can show you any of thetoolswith which they work, though a large portion of their work is like that of man; and they have, too, several customs which our fellow-creatures have. I can tell you, however, of several other animals which do use tools shaped like those used by men, if you would rather hear of them."
"If you please, Uncle Philip, we will hear of them at another time; but now we would rather have you tell us of the other kinds of ants."
"Oh, very well, boys; it shall be as you wish. All that I desire is to instruct and amuse you, and I am sure that the ants can furnish a good lesson to us. I shall begin with the mason ants. They always build their nests either of clay which is damp, and dug from the inside of their city under ground, or which has been made wet by the rain; and a part of their building is always above the ground, so that you can easily see it. There is no fixed rule for the ants to build by. Their cities are not all alike in the inside. Sometimes the walls are larger and coarser, and the ways and galleries are higher, than at other times. The rooms, too, are different in shape and size, so that this industrious little insect seems to have sense enough to work in the best way according to circumstances. There is only one general rule which they seem to have, and that is always to build in a number of different stories, one above the other. If you examine one of these stories you may see a number of large places or halls, some smaller rooms, and some long galleries whichserve as passage-ways. The tops of these large halls are covered with an arched ceiling, and this ceiling is held up, sometimes by little columns, sometimes by very thin walls, or by props built against the side walls, just like buttresses. There are also chambers which have but one door, which opens into the lower story, and large open places in the centre of the nest something like a cross road, and all these little galleries or streets come into that open place."
"Any bridges, Uncle Philip?"
"No, boys; no bridges among these ants, so far as I know. There will sometimes be as many as twenty stories above ground in the ant-hill, and as many below. The best time to see these little fellows at work is in a gentle shower of rain, or directly after."
"Why do they work in the rain, Uncle Philip?"
"I suppose, boys, it is because the earth is then better for them; and one thing that has been noticed about their work is, that the rain, when it is not too violent, seems to make it solid, for these ants have no gum or glue about them like some other insects, to make the earth stick together. As soon as the rainbegins, if you watch the brown ants, you may see them come out of the ground in great numbers; and then running in again, they will soon return, each one with a little piece of dirt in his mouth, which he puts down upon the roof of the nest. A gentleman who watched them very closely[10]says, that at first he could not think what this was done for, but at last he saw little walls begin to rise up with spaces left between them. In some places pillars were begun, placed at regular distances, and he knew that these were to support ceilings; so he found out that they were going to build another story to their house, and they were laying the foundations."
"How I should have liked to see them. Uncle Philip. I would not have cared for the rain."
"Ah, I see you are fit to be a naturalist. You know what that word means, do you not?"
"It means, Uncle Philip, a man who loves to study about the animals and insects, does it not?"
"It means a man or a woman either, boys, who loves to study the things in nature nomatter whether they are animals, or stones, or grass, or flowers, or any of the things which God has made. Mark, boys, I said to study the things, and you said to studyaboutthe things. Now a person may read a great deal that is interesting and true about all these things in books; and it is very well to do so; but I think that the real naturalist will never be satisfied with books only; he will be looking to see things for himself. And I said a woman might be a naturalist, because some ladies have been fond of natural history, and have proved themselves to be very good naturalists. But let us go back to the ants. Mr. Huber, in the account which he gives of his having watched these little workmen, never thought of telling us whether he got wet or not, because he was too busy to think or care much about it. He had an opportunity of seeing what he might never see again, and a little rain was not to spoil it. He says that each ant, as it brought out its little lump of dirt, would place it on the spot where it wished it to be, and press against it with its teeth, so as to make it fit closely. It then rubbed its feelers all over it, and after that pressed upon it lightly with its fore-feet.The walls went on very rapidly, and it often happened that two little walls, which were to make a passage or gallery, would be raised opposite and at a small distance from each other. When they were about a quarter of an inch high, the ants would set to work and cover them with an arched ceiling. After they had raised all the walls as high as they wished, on the inside of each wall at the top they began to put in pieces of wet dirt almost level, and in such a way as to make a ledge; and by joining on more dirt to it, it would meet the ledge made from the opposite wall so as to make a roof: these roofs over the galleries were about a quarter of an inch across. The ceilings over the large halls were sometimes as much as two inches in breadth, and to support these they raised pillars; and beginning in the corner where two walls joined, they would commence the ceiling with a ledge, while from the top of each pillar they would also build out a layer of earth a little rounded on the top; these they continued to add to until all met and made a complete cover for the hall."
"I wonder it did not fall, Uncle Philip, before they could join it together."
"Mr. Huber says that he thought several times it would fall, from the rain which was dropping upon it all the time; but he found that the pieces held together, and that the rain, instead of hurting it, only made it more solid. All that it wants, when the ants have done, is a little heat from the sun to bake it hard, and then it appears like a piece of solid dirt. Sometimes, if the rain be violent, the apartments will be destroyed, especially if the arches are not built strongly; and when this happens, the little creatures go to work very patiently and rebuild them."
"And how long, Uncle Philip, did it take the ants to put another story on their house?"
"Between seven and eight hours; and they had hardly finished one before they began another, but they had not time to finish it, for the rain stopped before they had built much: however, they kept on, taking advantage of the wet earth; but a cold drying wind soon sprang up, and the earth would not stick; so they stopped: but what do you think they did with the new story which they had not time to finish?"
"Whatdidthey do, Uncle Philip?"
"Pulled every part of it to pieces, and scatteredthe dirt here and there over the roof of the story which they had finished.
"I will tell you another story about these ants, boys, which I think is most wonderful, because it appears so much like reason. These insects all seem to work separately,—I mean without attending to the work of others: of course sometimes the work done by different ants on opposite sides of the same gallery or hall will not suit: one wall will be higher than the other, so that the ceilings will not meet. Mr. Huber saw just such a case; the ceiling which was begun from one wall would just have reached the other wall about half-way up; and while he was wondering how the ants would cure the fault, one of them came, and looking at the work, seemed to know that it was wrong, and immediately began by taking down the ceiling from the lower wall; he then raised it to the same height with the opposite wall, and made a new ceiling in Mr. Huber's presence with the pieces of the old one."
"Uncle Philip, if that ant did not know how to think, I am mistaken."
"I must confess, boys, it does seem very much like thinking; and if it was not thinking,we must at any rate own that it was something which,in this case, did quite as well; for no thought of man could have hit upon a better plan. But if the ant knew how to think as a man does, do you suppose it would ever have made the mistake? Would not the workmen have all agreed beforehand what they were to do, and how it should be done, so that there might be no need of pulling down any of the work because it would not suit? I think that this story, boys, while it shows us something like reason inoneparticular instance, shows us also thatin generalthe ant has not reason like ours. But I am tired now, and can tell you no more this morning. When you come again I shall be ready to talk with you about some other kinds of ants. But before you go, tell me—can any of you inform me what the Bible says about the ant?"
"Oh yes, Uncle Philip: it says, 'Go to the ant, thou sluggard, consider her ways, and be wise.'"
"Well, another question. Have you any lessons to say when you go into school on Monday?"
"Yes, Uncle Philip; we have."
"Have you learned them, boys?"
"No, sir."
"Then remember what the Bible says to the sluggard, and go and learn them at once. Good-by, children."
"Good-by, Uncle Philip: we will learn our lessons."
FOOTNOTE:[10]Mr. Huber the younger.
[10]Mr. Huber the younger.
Uncle Philip tells the Boys about Ants that go to War and fight Battles; and about some that are Thieves, and have Slaves.
"Well, my lads, how do you do to-day?"
"Very well, Uncle Philip, we thank you. And we wish to let you know that we kept our promise to learn our lessons. Our teacher was very well satisfied with every one of us."
"That is well, boys. I am truly glad to hear this from you: and I make no doubt that you also felt a great deal happier than you would have done had you neglected to learn your lessons. Did you not?"
"Oh yes, Uncle Philip, much happier; and far more cheerful and good-natured."
"Such are apt to be the feelings, boys, of those who have done theirduty. I am verily persuaded that there is no such thing as real, solid happiness in this world, but in that man who acts from a sense of duty. His is true peace, because it is 'the peace of God.' I do not say, boys, that a man, even when he does his duty,alwaysfeels comfortable or happyat once; but he will be more apt to feel so than if he did not do his duty: and I do say that no man who does not act from a sense of duty, is likely to feel any thing like happiness very often or very long."
"Then, Uncle Philip, a man who wishes to be happy will try in the first place to find out what his duty is."
"To be sure, he will; and he need not try very long either, if he really wishes to know it. The will of God, boys, is at the bottom of all our duties; and an honest man, yes, or boy either, can commonly tell what God will think to be right or wrong in his conduct. You know where a great many of our duties are very plainly written down for us; do you not?"
"Oh yes, sir; in the New Testament, which tells us of what our Saviour said and did."
"True. And what our Saviour commanded, boys, God commanded; for He is God. But besides this, when it is not exactly written down in the New Testament what we should do, still if we will think, we shall very often find out what to do, from what is written."
"Uncle Philip, we almost always know what you mean; but now, we do not quite understand you."
"Thank you, boys, for telling me that you do not know what I mean: always tell any person who is trying to teach you something, when you do not understand what is said to you. Now I will try to make what I said plainer to you. The New Testament does not say any thing about your going to school; does it?"
"No, sir."
"Who sends you to school, boys, and pays your teachers for instructing you?"
"Our parents, Uncle Philip."
"Very well. Now suppose that John Carter here, should wish, instead of going to school, to do, what I am very sure he never did do:suppose he should determine to play the truant. The Bible does not say a boy shall not play the truant, does it?"
"No, Uncle Philip."
"But if John Carter should play the truant, he would, in doing so, disobey what God has commanded in the Bible just as much as if the Bible did say 'A boy shall not play the truant;' for the Bible does say, 'Children obey your parents,' and he could not be a truant without disobeying his parents, who bade him go to school."
"Uncle Philip, we understand you very well now."
"There is another thing I wish you to understand, boys. John Carter, as you see, would not only disobey his parents, which is wicked, but he would also commit asinagainst God. That is always the thing to look at first. When we are going to do something that we are not very sure is right, we should always stop to ask ourselves whether God will be pleased with it. But I have said enough to you about our duty for this time. Now for the ants I promised to tell you of. And the first sort I shall mention are great fighters."
"Fighters, Uncle Philip! What do they fight about?"
"About trifles, boys, just as men do. They have terrible wars, and will dispute with and kill each other for a few inches of dirt, when certainly this world is large enough for them all. But animals wiser than ants, boys, act in the same foolish way. Men sometimes go to war and kill each other to determine who shall have a river, or a small town, or a fort, or some little spot of ground; while the poor creatures who do the fighting, and get all the wounds, and lose their lives, had they been let alone, would have lived on in peace, and never cared a straw who had the miserable little spot they fight for. But let me go on with the account of these ants. In the forests, where the fallow ants live, you may see these wars. The battle will be between the ants of different hills, but they are all ants of the same sort. Thousands and thousands of them will meet on the ground between their hills, and the battle begins by two ants, who seize each other by the claws (ormandibles, as they are called), and rising up on their hind-legs, they bring their bodies neartogether, and spirt a sort of venomous or poisonous juice upon each other. These will be followed by thousands of others on both sides, who seize each other in the same way, and fight in pairs—ant to ant. Sometimes they will get so wedged together that they fall down upon their sides, but they do not let go on that account; they keep on fighting in the dust until they rise on their feet again. Sometimes, too, a third ant will come in, and joining whichever of them belongs to his nest, the two will begin to drag the third, until some of his friends come to his help; and in this way, others joining on both sides, they will form strings of six, or eight, or ten on a side, pulling with all their strength. And while some are fighting, you will see others leading off prisoners towards their hills, while the prisoners are trying to escape. The field of battle is not more, perhaps, than three feet square; multitudes of dead ants covered with venom may be seen upon it, and there is a very strong scent which comes from it. When night comes they go off to their hills. Before dawn the next day they are at it again in still larger numbers, and they fight with greater fury than before, untilat last one side or the other gives way. They are so busy that even if you stand near them they take no notice of you, and not one stops fighting, or crawls up your legs."
"Do all of them that belong to the hill go out to fight, Uncle Philip?"
"No; near the hills all is peace and order, and work seems to be going on as usual. Only on the side next to the battle, crowds may be seen running backwards and forwards from both hills; some as messengers, I suppose, and some to fight, or carry back prisoners."
"But, Uncle Philip, you said that these ants were all of one sort; how then do they know one another so as to tell which party each one belongs to? I should think that sometimes they would make a mistake, and fight a friend instead of an enemy."
"This, boys, is one of the most wonderful things concerning them. They are alike in form, and size, and weapons, and strength; and sometimes it happens that they do make a mistake, but it is very seldom; and when they do, Mr. Huber, who watched one of their battles, says that they find it out directly, andcaress each other with their feelers, and make up the difficulty at once.
"Are you tired, boys, or do you wish to hear more?"
"Oh, let us hear more, by all means: we are not at all tired."
"I will then tell you of another kind of ants called legionary ants, and sometimes amazons; but I am sorry to say that they are unlike other ants, for they are lazy; and yet they live very comfortably."
"How is that, Uncle Philip? Can they be comfortable without working?"
"Yes, boys, if they can get others to work for them; and these have their work mostly done by their slaves."
"By their slaves! what are their slaves, and where did they get them?"
"As to your first question, boys, their slaves are ants of another kind; as to the second question—where they get them—theystolethem when they were young."
"Why you surprise us, Uncle Philip."
"I dare say I do. There are persons much older than you are who have never attended at all to the doings of insects, who would be very much astonished by the history of thelegionary ants; and probably would laugh at the whole account as an idle story; and yet it is all true, and those who have read and seen, know it to be true; and they know, too, that to deny it shows nothing but ignorance. However, I always let such persons alone. I can do them no good; for they are apt to be very conceited, and will not be convinced. And now for the legionary ant. This is a fighting ant, as well as the last I mentioned; and it actually steals the young of another kind, rears them, and puts all the work on them, so as to be idle itself. This curious fact was first found out by Mr. Huber; another gentleman, named Latreille, afterward saw the same thing; and now a great many naturalists know it, because they have sought for and seen it. The ant which it steals is of a dark ash colour; the legionary is of light colour. The dark-coloured ant is now called the negro ant, and is a very industrious, peaceable insect, without any sting. The legionary is a strong, brave ant, with a sting, but very lazy. I shall relate to you the account which Mr. Huber gives of the legionary. He was walking near the city of Geneva during an afternoon in the summerof 1804, when he saw quite an army of these legionary ants crossing the road; they passed through a thick hedge, entered a pasture, and kept on through the grass without separating; and Mr. Huber followed them until he saw them come near a nest of negro ants. Some of these negro ants seemed to be guarding the holes into their nest; but as soon as they saw the legionaries, they, with a great many more from the inside of the nest, attacked the thieves. The legionary ants, however, were too powerful for them, and after a short but severe fight they conquered the negroes, who ran into the lower part of their nests. The legionaries then mounted their ant-hill, some entered it by the holes already made, and others began with their teeth to break other holes, so that all the army might get into the hill. They went in and remained but a few minutes, when they came out, each one having in his mouth a young negro ant, and off they scampered, without any order among them, every one going his own way, until Mr. Huber lost sight of them. The next day he set out to go back and examine further, and on his way he found a large ant-hill full of legionaries, and saw an army start from it,which he followed. They made the attack as before, and each one came off with a young negro ant in his mouth, and on going back to their hill, from which Mr. Huber saw them start, he had an opportunity of seeing them return, and was very much surprised to find all around the nest of the legionaries a great many full-grown negro ants. At first he thought that perhaps they had gone there to fight the legionaries, but he soon saw that instead of fighting, the negro ants went out to meet the legionaries returning, and would caress them, and give them food, and finally take the young negro ants and carry them within the nest."
"But, Uncle Philip, why do the legionaries always take the young ones?"
"Because, boys, they know, I suppose, that the old ants would never be satisfied to remove from their homes; and therefore they take the young. These legionaries could work if they would, I think, but they depend upon the negro ants for house and home, and food too; and nothing can be more faithful and affectionate than these poor slaves are. To try them, Mr. Huber took thirty of the legionaries, and put them with some of the larvæ,or grubs of their own young, into a glass box with a thick coat of earth at the bottom of it, and he put honey also in the box, that they might not want food. At first the legionaries paid a little attention to their young; but they soon stopped; and they neither tried to make a house, nor took any food, so that in two days half of them died. Mr. Huber then put inonenegro ant, and this little creature set to work alone, made a chamber of the earth in the box, gathered the young together, fed the old, and put every thing into complete order.
"At another time Mr. Huber broke one of the ant-hills of these legionaries, to see how they would act, and in doing it, he, of course, altered their galleries and chambers. The legionaries seemed to be lost, and went wandering about, without knowing where to go; but the negro ants appeared to understand very well where they were: they could find such of the galleries as were not broken, and would take up the legionaries in their mouths and carry them into them. If the negro sometimes seemed for a short time to be lost, and not to know where it was, it laid down its master, ran round and examined until it knew, and then would come back, and pick up thelegionary ant, and carry it off. In one case Mr. Huber saw that the entrance to a gallery was stopped up by a small lump of earth; the negro ant laid his master down, took away the piece of earth, and then carried him in."
"Why, these poor negro ants are sensible as well as faithful, Uncle Philip."
"Yes, boys, they are so; and I think it is likely that both kinds depend in some way upon each other, but we have not yet found all about it. I expect that in some things the legionary does for the negro ant what it could not do for itself. God has made them necessary to each other, and this is the reason they live together so kindly.
"But I think it is time now to leave the ants, and go back to our business of seeking for something like man's inventions and tools among the lower animals. Perhaps hereafter I may tell you more about ants; but at present I must bid you good morning."
"Good morning, Uncle Philip."
Uncle Philip and the Boys make a Voyage, and he tells them of an Animal that makes itself into a Ship; and of an Insect that builds a Boat, and floats about in a Canoe; and of another that pumps Water, and wears a Mask; and of a Spider that builds a Raft, and floats upon it.
"Well, boys, I have a most delightful plan for us to-day."
"What is it, what is it, Uncle Philip?"
"Why, I have a little voyage to make, and my boat is on the river just above the mill. I have the men there to row it, and every thing is ready."
"Oh! dear Uncle Philip, this is charming! we shall be so happy! But—but—"
"But what, boys?"
"Why, Uncle Philip, we have not asked leave at home. Now our parents are very happy to have us visit you, and say that they are very much obliged to you for telling us somany things; but they have told us, too, never to get into a boat without asking their permission first. Uncle Philip, we are sure they will let us go, if they know that you are going; only let us run home and ask them."
"My dear boys, I am very much pleased with your conduct; and, what is far better, my children, God is pleased; for he has commanded you to honour your father and mother: but you need not go home to ask permission, for you may depend upon it I would not take one of you upon the water without the consent of your parents: so I went yesterday, while you were all at school, and have got permission from your friends for every one of you to go—only I asked them to tell you nothing about it."
"Oh dear, Uncle Philip, you are so very, very good: thank you, thank you, a thousand times over."
"Once is enough, boys. There is but one Being who deserves a thousand thanks, and he, in truth, deserves a great many more than a thousand; but I fear that from a great many he is just the Being who gets the fewest,—it is our Heavenly Father: but come on, boys, let us be going to the boat. Weshall soon reach her. Ah, yonder she is; I see her through the trees."
"Oh, what a beauty she is, Uncle Philip, with her green sides and white belt near the top. We shall have a charming voyage."
"Come, then; get in, my little sailors, and seat yourselves yonder in the stern. Now we are all ready; shove off, men, and use your oars. I will take care of the helm."
"Oh, Uncle Philip, how smoothly we go along! this is charming. Is this the way a ship goes, Uncle Philip?"
"A ship floats, boys, just as the boat does; but she is not rowed with oars; she has sails, and the wind blowing upon them sends her along."
"Uncle Philip, there are no ships among animals, are there?"
"Oh no; but there is a very curious little animal which lives in the water, and manages to rig out something like a ship, and to sail."
"What is it, Uncle Philip? pray let us hear of it."
"It is called the nautilus, and I saw a great many of them in the Mediterranean sea. The shell is nearly round, and six or eight inchesacross, not much thicker than paper, and of a whitish colour: it has, too, a keel or ridge upon each side. When it wishes to sail, it stretches upwards two of its legs: these have a very thin skin at the end, which the nautilus spreads out for sails, and the other legs hang over on each side of the shell for oars or rudders. When the sea is calm, a great many of them may be seen playing about; but as soon as a storm arises, or they are disturbed, they take in their sails and sink to the bottom. But, boys, the most curious boat that I know, made by one of the dumb creatures, is the work of the little insect that played the doctor the other day, and stuck his lancet into us. Do you remember what insect that was?"
"Oh yes, very well, Uncle Philip, it was the gnat."
"True, boys, it was the gnat, which is an insect that spends the first part of its life in the water, and the latter part in the air. The grub of the gnat lives in water, and I will give you the whole history of this curious insect. We will first speak of the eggs, for out of these it is that the boat is made. In order to see this boat made, you must goearly in the morning, between five and six o'clock, to a bucket, or pond of stagnant water, where gnats are to be found: if you go later you will not see it. The gnat's eggs are shaped something like a pocket powder-flask, and it is by putting a great many of these together that she makes the boat. To do this, the mother gnat stands by her fore-legs upon the side of the bucket, or on a leaf or stick in the pond, and her body is on a level with the water, and rests upon it, except the last ring of her tail, which she raises a little. She then crosses her two hind-legs in the shape of the letter X, and begins to put her eggs in that part of the X nearest to her body. So she brings her legs, crossed in this way, near to her body, and puts an egg in the angle, covered with a kind of glue, which will make the eggs stick together. On each side of the first egg she puts another in this shape ⁂, and here is a drawing of the insect at this part of her work.
A Gnat making her Boat of EggsA Gnat making her Boat of Eggs.
A Gnat making her Boat of Eggs.
"She then goes on adding eggs, which are all put in the water with their ends downwards, until she has got her boat half-finished; she then uncrosses her legs, and just keeps one on each side of the boat as she goes on, until she has completed it."
"And how many eggs, Uncle Philip, will she put together in this way?"
"From two hundred and fifty to three hundred and fifty, and when all are laid they make quite a good boat, sharp, and raised at both ends, and floating on the water. Then the mother gnat leaves it. Here is a picture of one of these boats.
gnat egg boat
"Now I will tell you of what becomes of the young ones in these eggs. They come out of the lower part of the egg, and commonly swim, with their heads downward, near to the top of the water."
"With their heads downward, Uncle Philip! what is that for?"
"Why, they have a tube at the end of theirbodies, near the tail, through which they breathe; and that part must, you know, be at the top to get air. Besides this, its tail and its breathing tube both end in a sort of funnel, made up of hairs placed somewhat in the form of a star, and covered with oil, so as to keep off water, and these buoy or float it up. When it wishes to sink, it just folds up its funnels, and shuts up in them a little bubble of air, which it breathes under the water; and when it wishes to rise, it opens its funnels, and they float it to the top again. Here is a drawing which will show it to you.
Larva of the common GnatLarva of the common Gnat floating in water, greatly magnified.aa, the body and head of the larva;b, the respiratory apparatus, situated in the tail;c, the larva, not magnified.
Larva of the common Gnat floating in water, greatly magnified.aa, the body and head of the larva;b, the respiratory apparatus, situated in the tail;c, the larva, not magnified.
"They are hatched in a few days, and then the boat of empty eggs floats about until it is destroyed by the weather. And to show you how good a boat it is, I will tell you what a gentleman did to prove it. Mr. Kirby, who is very fond of natural history, and has written a great deal about insects, says that he put half a dozen of these gnat-boats in a tumbler half full of water, and then poured upon them a stream from the mouth of a quart bottle, held up a foot above them, and he could not sink them. More than that, the water would not stay in them. If you push one to the bottom with your finger, it will come up to the top directly, and you cannot see any water in it."
"Why, this is a noble boat, Uncle Philip, that will never sink."
"True, boys; but listen, and you will find that before it can use its wings the gnat has to sail in another boat still, much more dangerous than this is. After it is hatched, it has to pass through several shapes before it gets to be such an insect as you see. Here is a picture which will show you its different shapes.
Gnat shapes
"The first is the same which you saw in the last picture, only in this drawing the head is uppermost. But its last change, when it becomes an insect with wings, is the most curious part of the whole. When it is about to get its wings, and become a perfect gnat, it raises its shoulders just above the top of the water, and its skin cracks, so that the head of the gnat immediately comes through. The shoulders come next, and make the crack larger; but it has yet all its body to get out, and its legs and wings are as yet all shut up in its case. Now is the time of danger for the gnat. It raises itself nearly straight out of the crack, and by wriggling works its body along: and if a particle of water should get upon the case, or touch its wings, it would be overset, and must perish. Thousands and thousands die in this way. It is so verylight, too, that the wind will drive it about, and whirl it round and round upon the top of the water; and when it is almost out, the insect is tossed about in a canoe or boat of the very weakest sort, while its body is a mast, which appears much too large for so small a boat. At last it gets far enough out of the case to stretch its fore-legs, and put them down upon the water (which will bear a gnat's weight), and then it is safe; it spreads its wings, and soon leaves the little boat which was so dangerous. Here is a picture of the gnat getting out of its case."
Gnat getting out of its case
"Well, Uncle Philip, all this is very strange; we never knew before that the gnat was a sailor."
"I suppose that you did not, boys. But as we are talking of boats, pray can you think of any way of making a boat move through water without oars, or paddles, or sails, or something to pull it along?"
"No indeed.—Oh yes, Uncle Philip, by steam."
"Ah, I mentioned paddles, boys, and a steamboat is forced along by them."
"No; Uncle Philip, we do not know."
"Well, I will tell you then of another way in which I have no doubt a boat might be made to move. If there were any contrivance by which a large quantity of water could be kept in the boat, and if this water were forced out of tubes or holes at one end very violently, it would push against the water in which the boat was floating, and force her along. Some years ago a plan was thought of to make a steam engine throw the water out of the stern of the boat, and thus to force her along; and before that, Dr. Franklin tried some schemes for the same purpose, but they never succeeded. Now there is an insect which adopts precisely this plan, and perhaps some of those who thought of it got the notion from the insect."
"What insect is it, Uncle Philip?"
"It is the grub of the dragon-fly. If you catch one of these grubs and put it into a saucer of water with some of the dead leaves or sticks it had for a covering, you will seethese leaves or sticks floating towards the tail of the grub, and afterward driven off again. This is because the insect is pumping in water, and then throwing it out. If you take one of them out of the water, and hold it with its head down, and let a drop of water fall upon its tail, it instantly sucks it in, and you can see it grow larger; and when it throws it out again it becomes smaller."
"But, Uncle Philip, how can you see it suck the water in?"
"Very easily, boys. When it is in the water, if you will colour some other water with indigo, or ink, or any thing else, and then hold a glass tube just over the tail of the insect, and very carefully put some of the coloured water into the tube, you will soon see the grub spirt out a stream of it to the distance of several inches: or if you will put the insect in a saucer of coloured water, and then suddenly move it, and put it into one of clean water, you will see it spirt out the coloured stream plainer still."
"Why, Uncle Philip, it must have a pump inside of it."
"It has, boys, something very like one. This stream of water is forced out to helpthe insect along; for though it has six feet, it uses them very little except for catching food. It drives the water out so strongly against the still water behind it, that it sends it forward, with a dart, very rapidly. Here are two pictures; one shows the pump open, and the other shows it shut."