The History of a Mouthful of Bread Part 20

LETTER x.x.xI.

MAMMALIA. _(Mammals)--continued_.

Let us continue to pa.s.s in review the different orders of the cla.s.s Mammalia. We may meet elsewhere with facts more important to science, but nowhere with any so personally interesting to ourselves.

ORDER 5. _Insectivora (insect-eaters)_.

This order devours insects, as their name tells you plainly enough.

They feed in the same manner as the bats; consequently they have molars like theirs, as was necessary. It is an unimportant little family, and we will not waste much time upon it. The chief of the order is the hedgehog, a native of our country--not very large, about nine inches long--which lives in the woods, and which when rolled up into a ball, with all its quills standing out, looks very much like an enormous horse-chestnut in its sh.e.l.l. Its canines have not much work to do, consequently they are very small; but, on the other hand, its two front incisors are prolonged beyond the others, the better to seize its prey, which creeps upon the ground. Internally there is nothing to remark upon.

Next to the hedgehog I will mention as a curiosity the shrew or sand-mouse, which, in spite of its name, is no mouse at all, but has the honor, if honor it be, of being the smallest animal known of the cla.s.s Mammalia.

It is about two inches in length altogether; and if you carefully examine its little body, you will find that it contains all the organs you possess yourself--oesophagus, stomach, liver, intestines, veins, arteries, heart, lungs--nothing is wanting: the machinery is absolutely the same.

ORDER 6. _Rodentia (rodents)_.

Were we to translate this word into its meaning, namely, the _Gnawers_, there would be some comfort in it, for we would at once know what it means: but no matter. Rodents, or Gnawers, are rats, hares, rabbits, beavers, marmosets, squirrels, in fact all the creatures which _nibble_.

To _nibble_, if you do not exactly understand the word, means to chew with the points of the teeth. The rodents have no other way of eating but by filing, if one may so say, their food with the points of two incisors with which both the jaws are provided; these incisors are very long, much longer even than those of the hedgehog. The next time you see a rabbit at table, ask to see the head; and you will find that it has four pretty little teeth, very sharp, shaped like a joiner's chisel; that is to say, with a "bevelled edge," to use the received expression; in other words, with one edge thinner than the other.

Here, then, we begin to diverge from the old model. First, there is a different fastening, or _articulation_, as it is called, of the jaw. Its _condyles_, which we saw just now in the _Carnivora_ enlarged transversely and deeply embedded in the _fossae_ or cavity of the temporal bone, extend here longitudinally; an arrangement which enables the jaw to move backward and forward at pleasure, like the arm of the locksmith when using the file. Furthermore, those little teeth, which are constantly rubbing against each other, would be very soon worn out, if, like our own, they were made once for all; accordingly their germ, or _pulp_, to use the proper term, instead of peris.h.i.+ng, as with us, when the tooth has once come, retains its life, and works on throughout the life of the animal. They sometimes say of a man who has not eaten for a long while, that his teeth have grown long. This is a joke with us; but in the case of a _rodent_ would be too serious a matter to be a joke; for, as their incisors are always growing, like our nails, they would soon become too long if the animal ceased for any length of time to wear them down by eating. It is for this reason that rats and mice have such incessant appet.i.tes, and that with them "all is fish that comes to the net;" old books, rags, and even planks of wood, which they will gnaw for want of something better. Come what may, they must keep up at an equal rate the wear and tear of the incisors, and the internal growth of the pulp beneath, which is always pus.h.i.+ng the tooth forward.

This dull continuous work might otherwise have a terrible result, which you would never suspect. It is very disastrous for a young lady to lose a front tooth, as it is called, for it sadly spoils a pretty face; but for a _rodent_ such a loss is much worse; in fact, it is a death-warrant. The corresponding tooth, having no longer anything to rub against, ceases to wear out; and as it does not stop growing on this account, it lengthens indefinitely, until at last it pushes out beyond the mouth, and places itself like a bar between the two Remaining teeth and the food of the animal, who, poor beast, being unable to eat, ceases to live.

The canines, whose duty it is to pierce the food, have, of course, no use in a jaw that grinds, nor are they to be found there. Between the incisors and the molars there is a large vacant s.p.a.ce, which you will easily detect if you examine a rabbit's head.

Finally, animals which can fall back in time of need on a plank for their dinner, require a very different-sized cooking apparatus to that of the _Carnivora_. Thus the rat, the most perfect sample of the rodent order, possesses a digestive tube of a prodigious length, through which the sc.r.a.pings of wood have plenty of time for travelling, while the minute nutritive particles they contain are being thoroughly disengaged; and as every part of the animal organization tends towards keeping our insatiable rodents in the constant state of voracity required by its inexorable pulps, nature has given it an enormous heart whose size exceeds even that of its stomach.

Perhaps you do not catch at once the connection which exists between the size of the heart and of the appet.i.te; yet it is very simple. Large barrels are requisite for those who brew a great deal of beer, and large hearts for those who make a great deal of blood. Now, it is the blood, as you know, which carries heat; in other words, life, throughout the body; when it pours in in torrents, the fire goes twice as fast, and, consequently, the feeding must be kept up. A medical friend of mine told me that he once had some rats sent to him--a boxful in fact--for one of those scientific experiments which one would venture to condemn more earnestly if their results were not sometimes beneficial. Next morning there were only two or three animals to be found, and these had eaten up the others. See the consequence of having too much heart!

ORDER 7. _Pachydermata (thick-skinned)_.

In Greek _pachus_ means thick, and _derma_ skin. _Pachyderms_, therefore, are thick-skinned animals. It is rather a vague denomination, as you perceive, and does not tell us much about them; but it appears that it was not very easy to find a better term. For my own part I should be very much puzzled to find a name really suitable for such an irregular company as this, in which all the huge beasts of the earth--the elephant, the rhinoceros, the hippopotamus--are heaped one upon the other, side by side with the horse, the a.s.s, and the hog; begging your pardon for an ugly word.

All these creatures live on vegetables, with the exception of the hog, to whom nothing comes amiss; or who, in other words, is _omnivorous_, like the bear, and also another member of the cla.s.s _Mammalia_, which I do not name for fear of making you blush at your companions.h.i.+p. This a.s.sures you that, in the order of the _Pachydermata_, the digestive apparatus is very fully developed. The horse, for instance, has a very voluminous stomach, which extends much farther back than the point at which the oesophagus empties itself; and in which, on close examination, a sort of contraction is observed which appears to divide it in half, producing the false effect of there being two stomachs. But, after all, we do not find, even in this case, any essential difference to remark upon in the internal arrangements; it is always the teeth we must look at if we want to have something to say. There, indeed, we have only to choose; nature has indulged herself in all manner of fantastic freaks.

To begin with the elephant, the grand master of the order, he presents us with one of the most oddly-furnished jaws in existence. Every one knows those two enormous tusks which protrude from his mouth, and which furnish human industry with nearly the whole store of ivory it has need of. Those two teeth are the largest, beyond comparison, of any in the animal kingdom; yet they are two merely ornamental teeth, perfectly useless in the operation of eating, and very ruinous into the bargain to the proprietor. All those stores of the blood which furnish the materials for ivory pa.s.s into these tusks, and, as often happens to people who give way to a taste for luxuries, there is nothing left wherewith to provide the animal with serviceable teeth. Those tusks of the elephant are nothing but his upper incisors, the only ones, observe, which curve in coming out of his jaw. In the lower jaw he has no incisors at all; canine teeth are entirely wanting; and by way of dental apparatus, this meagerly-furnished mouth possesses on each side of either jaw one or two molars, enormous in size, but not of ivory. They are composed of a number of enamelled upright layers of tooth-substance (_dentine_), soldered together with a bony cement; and these are our giant's only resource for chewing the gra.s.s, young shoots, and leaves of trees, which are his natural food.

[Footnote: These teeth are nevertheless very efficient grindstones.]

As a consolation, he has the glory of knowing that he possesses the very finest teeth in the world, the terror of all who approach him; and I can compare him to nothing so well as to a vain woman, who is contented to live on potatoes that she may wear fine clothes and excite the envy of her neighbors.

The hippopotamus also has incisors in the upper jaw, which curve as they come out of the mouth; but these never attain anything like the size of the elephant's tusks, neither do they hinder the development of the other teeth, of which this animal has a very respectable collection. The upper incisors bend downward; those in the lower jaw stand out horizontally, and terminate in sharp points like plough-shares; and indeed the hippopotamus uses them for tearing up the ground in order to get at the roots which form its nutriment. These are, besides, formidable weapons, with which when enraged the animal can tear even boats in pieces; for, as you are aware, the hippopotamus is almost amphibious, and browses on water-plants, and lives in the great rivers of Africa, its native country. Its name alone would have told you this had you understood Greek; [Footnote: _Ippos_, a horse, and _potamos_, a river. The Greeks, who had seen the hippopotamus in the Nile, in Egypt, named it the river-horse; as afterwards the Romans called the elephant the ox of Lucania, because they first saw it in Lucania during the war with Pyrrhus.] but I have no complaint to make this time, for it was the Greeks themselves who gave it. You would find it very awkward, would you not? if you had to breakfast at the bottom of the Thames, and could not swallow a morsel without having your nose filled with water? But the hippopotamus labors under no such inconvenience. Its nostrils are provided with two little doors, which it closes at will, and behind this screen the lungs keep quite quiet while the animal goes backwards and forwards in the water. There is generally a hippopotamus in every large menagerie. The next time you visit one look at him. You will see him with a large stomach almost trailing on the ground: and no wonder; he needs plenty of room in which to stow away all the canes, reeds, and water-plants from the bottoms of rivers, which are not very nutritious food. Accordingly the stomach of the river-horse presents the appearance not only of two compartments, like that of the true horse, but looks as if it were divided into three or four.

To conclude my account of this animal, I must add that the ivory of its teeth is even more beautiful than that of the elephant's tusks, and that dentists carve it into very magnificent teeth for their patients. This is not a matter to interest you much at present, but we never know what may happen. I advise you, however, never to make use of hippopotamus's teeth; they turn yellow very quickly, and, when people are driven to buy teeth, the least they can try for, is to get good-looking ones for their money.

I should like to say something about the rhinoceros while we are on the colossal tribes, but it is a very unsatisfactory subject. The animal has no canines, sometimes no incisors even; sometimes it has as many as thirty-six teeth, according to the species, as naturalists aver; and this is all I have to say about this great lump of flesh, so misshapen outside, yet so regularly formed within. He it is who especially deserves the t.i.tle _pachydermata_, his skin being so hard and thick that bullets glance off its surface. But this has nothing to do with our present subject, any more than the horn upon his nose, whose turn for description may come if I ever give you the history of the skin and all connected with it.

The hog also has canines, and very strong ones; but it is in the wild state, when it is called a boar, that these appear in their real form.

There we find them projecting out of the mouth with a curve, as is so commonly seen among the _pachydermata_, forming those terrible, sharp, and pointed tusks which have been so often fatal to the hunter.

The wild boar of the forest is supposed to be the original ancestor of the domestic pig; and if, as is probable, this is really the case, we have here a remarkable instance of the effect of man's treatment upon the organisation of the animals he collects around him. The wild boar lives only on fruits and roots, which, like the hippopotamus, he tears up with his tusks, those safeguards of his, amid the many perils of his life in the woods. In the service of man, on the contrary, he becomes lazy, cowardly, and greedy; unlearns his energy and combativeness, eats all that is offered to him in the trough, even meat, when it happens to be thrown in; and, in order to do this moreeasily, has recalled toward his mouth those formidable war-tusks of his, so tremendous as weapons, so useless as teeth; has, in fact, turned his sword into a fork. It is the case of a Tartar degenerated into a Chinaman. [Footnote: China, about which we have heard a great deal of late years, has been several times invaded by the warrior hordes of Tartary. But at each time, unto the second and third generations, the vanquishers have taken the effeminate manners, the costume and the usages of the vanquished, and so many conquests have only resulted in converting millions of Tartars into Chinese.]

This suggests to me an idea relative to the horse, the last important member of the _pachydermata_ which remains to be spoken of. It also has its canines, but very small ones; they disappear, so to speak, in a large vacancy between the incisors and the molars, where man inserts the bit, by means of which the animal has been subdued. Small as these are, however, these canines indicate that the horse might eat flesh, canine teeth being the distinctive attribute of the carnivorous mammals. I have read somewhere, but I do not remember where, that an unusual development of strength could be produced in the horse by feeding it on flesh; and the old Greek poets write of a king [Footnote: Diomed, King of Thrace] in the barbarous ages who gave his horses, men for food. If I knew some rich professor who was inclined to spend money in the investigation of a curious fact, I would advise him to set apart a sum for putting horses on a meat diet, from sire to son, gradually increasing the quant.i.ty; and I would boldly warrant that in the course of successive generations the canines would become so large as to impede the entrance of the bit into the mouth, and, moreover, would make it rather a ticklish office for the groom to place it there.

But let us set aside the teeth the horse might possibly have, in order to examine those it has already. There are six incisors in each jaw; these are long and rather projecting teeth, by examining which, the age of the horse can be detected from certain marks which appear in them from year to year. The molars are flat, square, furrowed with bars of enamel, marking out more or less distinct crescents; perfectly constructed, in short, for chewing hay and oats. Nevertheless, I should never be surprised to see the enamel crescents become sharp-cutting in our rich professor's stable; so skillful is the unseen Architect who created animals, in altering the house when the tenant changes his habits.

ORDER 8. _Ruminantia (ruminants)._

I shall retain through life a pleasant recollection of the _ruminants_. Through them I obtained the first prize for natural history which was ever given in France to the pupils of the learned university. It is thirty years ago since this happened, and I own, without any false modesty, that even now the word _ruminant_ rings very agreeably in my ear. It reminds me of one of the proudest moments of my life, of the honor done to me by the ill.u.s.trious Geoffroy St.

Hilaire, when he called me, a little college urchin, up to him, that he might have a nearer view, as he said, of the baby-professor who had spoken so well on ruminants. Yes, it is more than thirty years ago, for alas! it was in 1831. There needed no less an event, as I have told you before, than the revolution of 1830 in France to induce the big-wigs of education to sacrifice two hours per week in one cla.s.s to the study of natural history. Yes, my dear child, it is only that short time ago since natural history became one of the subjects of study in French colleges; and the gray-haired men of the present day finished their education, as it is called, without having learnt a single word of what I am now taking the trouble to teach you, a mere child. You see you have come into the world just at the right time, and will be able to instruct others in your turn. But before giving lessons to other people you must first finish learning your own. Forgive me this involuntary reference to a happy time when I was not much more rational than you are. And now, let us return to our ruminants--those dear, good beasts, the nouris.h.i.+ng fathers of the human race.

LETTER x.x.xII.

MAMMALIA--_continued_.

ORDER 8. _Ruminants--continued_.

Every created thing has an appointed part to perform; but there are some mysterious parts of which we cannot understand the drift. That of the ruminants, however, is so clearly marked out, that we detect it at a glance.

To qualify myself for supplying your young mind with the food I am going to offer it to-day, I have been obliged, my dear child, to browse in a good many books of which you could have understood but little yourself; and I have been forced to ruminate a long time upon what I have read, and to digest it slowly in my head, which I may say, without vanity, is of larger capacity than yours; no great wonder at my age.

Now, if I have succeeded in my undertaking, you will benefit by all the work which has been going on in my mind for the purpose of feeding yours without over-fatigue to it; and I shall almost have the right to say that its nourishment has been derived from me. My lamp could tell you what it has sometimes cost me to supply a single page which might instruct, without repelling you.

Now, this is precisely what the _ruminant_ does. The part he has to perform is to collect in the meadows a sort of food, which would disgust less well-organized stomachs than his own, to work it well up within him, and to give it back in a more palatable and less indigestible form. The little flesh-eaters (_carnivora_) come afterwards to the feast, and the feast is himself!

The whole history, then, of the ruminant is to be read in his stomach.

His real office is to digest, and in fact he devotes the best hours of his days to the perfecting of that beneficent labor, on which the life of so many weak stomachs depends. Have you ever amused yourself by watching a large ox lying down in a meadow? Long after he has finished grazing, his jaw continues to work, turning round and round like the grindstone of a painter when he is rubbing down his colors.

Look, and you will see that he will remain there for hours together, motionless and contemplative, absorbed in this incomprehensible mastication, rolling about in his throat from time to time some invisible food. Do not laugh at him, however. As you sec him there he is performing his part in life, he is _ruminating_.

To ruminate is to chew over again what has been already swallowed; and, however droll this may seem to you, it is the business which all ruminants are born to. You remember the monkey's pouch, which serves him as a larder, whence he takes out his provisions as he wants to eat. The ruminant has an immense pouch of the same kind, into which, while he is grazing, he hastily conveys large ma.s.ses of half-bitten gra.s.s. You probably think he is eating when he has his head down in the gra.s.s; but you are mistaken. This is only a preparatory work; he is hastily heaping up in his larder the food he intends to eat by-and-by; only his larder, instead of being, like the monkey's, in his cheeks, where, indeed, there would not have been half room enough for those great bundles he tucks in, is in the middle of his body, close to the extremity of the oesophagus, whose lower wall, being slit at that part, becomes an imperfectly secure tube, ready to burst open under pressure, and allow the food to escape between the edges of the slit; these, otherwise, remaining naturally closed. As soon as the large bundles of gra.s.s come to this part, they press against the walls of the tube, which they by this means separate, and fall into the provision-pouch, which bears the name of paunch, or gra.s.s-pocket, in fact. As soon as the paunch is well filled, and the animal sure of his dinner, he lies down in some quiet corner, where he proceeds gravely with the important act, which is the real object of his existence. A little below the entrance to the paunch, and communicating both with it and the ca.n.a.l of the oesophagus, is a second receptacle, which old French naturalists, not being much acquainted with Greek, named the _cap_, on account of its fancied resemblance to the caps worn on the head, and which we call 'king's hood' or 'honey-comb bag.' This second stomach now contracts (at least so it is supposed), and thus retains, as if with a closed fist, a portion of the gra.s.s acc.u.mulated in the paunch: of this it forms a pellet, which it sends back into the oesophagus, and the oesophagus, by continued contractions from below upwards, returns it to the mouth, where at last the gra.s.sy lump is chewed in good earnest, and to some purpose. There is no necessity for hurry; the ruminant has no other business on the face of the earth but this, and thus hour after hour pa.s.ses away, the food pellets rising one after another to the onslaught of the teeth. Nor do they go back again until they have been reduced by long mastication into an almost liquid paste, which glides through the oesophagus without forcing open the slit, and falls straight into a third pouch, called by old Frenchmen the _leaf_, on account of certain large folds, some what like the leaves of a book, which line the interior; and known to us as the _manyplies_.

From this stomach, No. 3, this gra.s.s-pap pa.s.ses into a fourth and last bag, which is the real stomach, and where the final work of digestion is accomplished. This fourth pouch also has a pretty little name of the old-fas.h.i.+oned sort, like the three others; it is called the _reed_ or _rennet-bag_, from the property it possesses, in the calf, of turning milk into curds: and of his four stomachs this is the only one which the ruminant makes use of at first. As long as the young animal is nursed by its mother, the other compartments remain inactive and small in size; they neither grow nor exercise their functions until it begins to eat gra.s.s. Indeed, they would probably entirely disappear, if any one would go to the expense of keeping the animal on milk all its life. If it ceased to have anything to ruminate, nature would certainly lose no time in relieving it of its useless workshop of rumination.

As it is right to give every one his due, I will mention that we owe our accurate knowledge of this simple and ingenious mechanism of _rumination_ to the labors of Flourens, a scientific Frenchman, who is still alive, and who has made a great many interesting inquiries into the subject we are now considering, _i. e._, the life of animals. He is a very clever man into the bargain--so perfect a master of his own language, that the French Academy has felt itself justified in opening its doors to him--an unheard-of honor for a member of the Academy of Sciences. And yet, in spite of all this, I heartily congratulate you that the discovery of the _paunch_, the _cap_, the _leaf_, and the _rennet-bag_, was not delayed for his arrival. He is just the man who might have been tempted, in his capacity of profound scholar, to have hunted up for them in the _Jardin des racines grecques_ [Footnote: Your brother can tell you about the _Jardin des racines grecques_. It is a charming little book, of which every generation of collegians has learnt, by heart, the commencement; but I have never known one, even among the most intrepid, who had ever been to the end of it.], four magnificent names, which would only have bewildered you.

Beyond the rennet-bag there is no change of conformation to note, except that the intestinal tube is naturally much longer than ours, on account of the difference of food: as a general rule, it is ten or twelve times the length of the body. The sheep, who is able to pick up a living in the poorest pastures, is indebted for this inestimable power, which makes him the special blessing of dry and barren countries, to a still further peculiarity of organization; with him the intestinal tube is twenty-eight times the length of the body.

We have seen among the _Carnivora_, whose jaws have so much work to do, that the condyles of the jawbone are sunk deeply into the fossa of the temporal bone. The ruminant, whose peaceful mouth is formed for contending only with gra.s.s, is organized quite differently.

Here the condyle is flattened, and the fossa of the temporal bone very shallow, presenting to the condyle an almost flat surface, so that the jawbone is enabled to revolve with ease for the better mastication of the pellets of gra.s.s. This conformation is also to be seen in the _pachydermata_ who feed upon vegetables. In the horse, especially, whose food is almost the same as that of the ox, the _articulation_ (as this joining of the condyle to the temporal bone is called) of the jaw, is also nearly identical; and it is the same with the teeth, with very trifling variations, those of all ruminants are constructed on the same plan as in the horse. The canines only require a separate notice.

But first I must tell you that, by some special privilege, the reason for which I do not undertake to explain, the order of ruminants is the only one containing animals with horns on their foreheads. Stags, goats, reindeer, chamois, gazelles, roebucks, oxen, buffaloes, all the beasts with horned foreheads, belong to the ruminants. Indeed, this fact would form a very convenient mark of distinction between them and other animals, were there not exceptions to it. Some ruminants have no horns; and then, as if in compensation for the deficiency, we find them provided with canines in the upper jaw, in addition to those below.

The ruminant which has the most beautiful canines is the musk-deer, a pretty little animal inhabiting the highlands of Central Asia, like the chamois of the Alps. But now that you know who he is, you will probably often be tempted to wish he had never existed; for it is from a small pouch below his belly that people obtain that odious musk of which Oriental beauties are so fond, and which even certain strong-nerved ladies of our own country are guilty of using in public, to the great detriment of general health. But enough of this; our business is with the canines of the musk-deer. They project with a descending curve from the upper jaw, and would give the animal the very false appearance of a small wild boar, but for the great delicacy of its legs, which are more slender than even those of our roebuck, to whom, with the exception of the horns, it bears a close resemblance, as its name implies.

After the musk-deer comes the large family of camels and llamas, which represent--the former in Asia and Africa, the latter in America--the irregular groups of ruminants which have canines instead of horns, and which seem to be placed as intermediates between true ruminants and the pachydermata. They form the connecting link between the horse and the ox, and men prefer employing them as beasts of burden to using them as butcher's meat; though one could eat them in their own country with less disgust than Europeans feel in making a meal of horseflesh; so that they might be a very acceptable resource in many cases. The real fact is, that ruminants with horns and without upper canines have more delicate flesh than the others, and seem more especially destined to be eaten. Yet if one had only to look at the stomach, which is, after all, the distinctive characteristic of the order, camels and llamas would stand in the first rank as ruminants. Besides the usual character of four stomachs, their paunch and honeycomb-bag are furnished with large cells which act as reservoirs, and fill with water whenever the animal has the chance of drinking freely, and from whence in time of drought he draws it up into his mouth and swallows it. This is what makes the camel so valuable to the wandering tribes in the great deserts of Africa and Asia. He is the only animal who can pa.s.s several days under the burning sun of Sahara without drinking--or rather without appearing to do so--for he carries his provision of water concealed from all eyes in the recesses of his body. I dare say you have often heard stories of Arabs dying of thirst who have opened the stomachs of their camels in search of a last draught of water. It must be a terrible thirst to drive a man to such an extremity; for, as you may imagine, one could not expect the water there to be either fresh or clear, to say nothing of the great risk there would generally be of finding the reservoir empty. Such an extreme is never resorted to till water has failed for a long time, and all the goatskin bottles have been emptied; and in such a ease it is but too likely that the camel has followed his master's example, and emptied his water-skins for his own use. But this is only half the internal fittings of the "s.h.i.+p of the desert," as the Arabs call him. In the desert it is often as difficult to find food as water; and nature has equally provided for this. The hump you see rising upon the camel's back in your picture-books is his safeguard against starvation. It is a huge ma.s.s of fat. I need say no more. You will remember Mr. Liebeg's pig, which lived 160 days upon its own bacon. Without going quite such lengths as that, the camel can keep up his fire for a long time upon the fuel which the blood obtains from this blessed hump. Since we are talking of this animal, and he takes a remarkable place in a history of nutrition, I ought to tell you that camels are cla.s.sed into two families by their hump: there is the camel, properly so called, which has two humps, and the dromedary, which has but one. This latter did not require such a supply of provisions as the other, for he is very much swifter of foot, and consequently his journeys are more speedily performed.

I have nothing particular to say to you about the other ruminants, in the matter of their organs of nutrition; but I will not quit the subject without reminding you of one thing which concerns nutrition, not theirs, however, but ours. It was by the taming of the domestic ruminants--that unfailing dinner-material which now follows everywhere at the heels of his master--that human civilisation began. Before that event, man, driven to depend for his living upon the hazards of the chase, spent his whole time in seeking for food, and had none to spare for the pursuit of any other branch of industry.

Far as we may ascend in the history of ages we shall find shepherd races. Beyond them there is no history at all, nor could there be. The first leisure hours of man, and, consequently, his first efforts in art and literature, date from the period when the ruminant animals, those special fabricators of nutritive aliments, were gathered around mankind, and worked out their destiny under the shadow of his tent, by his direction, and for his benefit. But all this is so distant from us now, that it is scarcely worth the trouble of thinking about. The human race is somewhat like those old people who have lost all recollection of their childhood; and young people are not required to know what their elders have forgotten. It is well, however, that they should not be quite ignorant on the subject. When you hear that the Society for the Prevention of Cruelty to Animals has taken up the cause of some barbarously-used ox or sheep, do not turn it into ridicule.

Those humble species have supported ours from the first; and you should recollect, now and then, that human society made its first step forward when it began to keep flocks and herds.