In these nests the northern alligator lays a great number of eggs, which she packs in mud, in several successive layers, one above the other, in the most singular manner. First she covers the floor of her nest with a sort of mortar which she spreads over it, made of mud and slime, and upon this lays one layer of eggs. This layer, when complete, she covers with another stratum of mortar, and over this lays another tier of eggs. The eggs have hard sh.e.l.ls, and are somewhat larger than hen"s eggs, and the monster lays so many of them as to build up her nest sometimes four or five feet high with these alternate layers.
When this work is finished the eggs are left to be hatched by the warmth of the sun, through the mother remains by them to guard them from the attacks of the pilferers that are always at hand in great numbers to steal and devour them. It has been said that in thus guarding these deposits the alligators in some sense make common cause, so that when one of the mothers has gone away to seek food, the others who remain watch over and protect her nest, and it is with some instinctive idea of this advantage that they adopt the plan of building their nests together.
There are sometimes not less than a hundred and fifty or two hundred eggs in a single nest. Of these, however, but a portion are hatched, and still fewer of the young arrive at maturity. The young that are hatched are watched and defended by their mothers with great care, but they are exceedingly tender and helpless, and great numbers of them are seized and devoured by beasts and birds of prey.
The greatest enemy of the alligator, however, is man. In gradually advancing the settlement of the countries in which they live, he intrudes more and more upon their haunts, and as their size is too great to allow them, like other reptiles, to secrete themselves from their pursuers, their numbers are all the time continually diminishing, and it is not improbable that before many years they may entirely disappear.
The crocodile of the Nile is an animal of the same general character with the alligator, but is of an altogether different species.
The Eagle
America is celebrated for its eagles. Indeed, one of the species, the bald eagle, so called, has been selected as the emblem of the national power. The eagles are all birds of prey, and they are remarkable for their size and the strength of their pinions. They seek their habitations on the summit of the various mountain ranges and on lofty cliffs overhanging the sea. From these elevated positions they survey vast regions of the air and watch for their prey. For this purpose they are endowed with powers of vision of almost incredible acuteness.
The eagle has always been held in high estimation by the American Indians, and his plumage has been prized more than that of any other bird for the dress and the decorations of warriors. This high estimation is derived partly from the warlike courage and propensities of the bird itself, and partly probably from the difficulty of taking him. Thus, eagles" feathers attached to a head-dress of a native chief, or ornamenting the shaft of a spear, were not only emblems of courage and strength proper to signalize the martial spirit of the wearer as a warrior, but they were also trophies of the daring and skill which he displayed as a huntsman, in scaling the lofty heights where alone they were to be procured.
The eagle is very long-lived. Some specimens have been known to live from eighty to a hundred years.
cochineal
The forests of America produce a great many different woods which have been used extensively in dyeing, and for other similar purposes in the arts, but the most important pigment that has been derived from the productions of this country is cochineal.
The cochineal is an insect. It is of the form of a little bug. It is a native of Mexico. It feeds upon certain species of cactus. Immense numbers of these plants are cultivated in Mexico and Peru, for the sake of the insects that feed upon them. The work of collecting these insects, which is very slow and tedious, is performed by women, who go about among the cactus plants and brush the bugs off into a basket with a little brush made of the tail of a squirrel, or of some other animal.
The insects, when collected, are killed by being thrown into boiling water, and then are carefully dried by being placed in ovens, or exposed to the sun. The article is then ready for market.
The cochineal insect produces a beautiful crimson dye, though a scarlet color can be obtained from it by a certain mode of using it. It is an article of very great value. Several millions of dollars" worth are annually exported from South America, and it is so precious that it is regarded in the markets of the world almost in the light of gold. Indeed it sometimes fulfills the functions of gold by being used for remittances and for making payments.
The Rattlesnake and Humming Bird
There are two other animals that remain to be mentioned among those that are peculiar to America--animals that, however dissimilar in other respects, are alike in this, namely, that each is marked by a very striking peculiarity of the same general kind, while nothing at all approaching to either exists in any other part of the known world. These two animals are the rattlesnake and the humming-bird. The peculiarity which gives them special distinction is a power of producing a sound by the motion of a part of their bodies--the humming bird by its wings and the rattlesnake by its tail.
The Rattle
The tail of the rattle snake is provided with several joints, formed of a bony substance, and put together in a loose manner, so that when shaken they produce a rattling sound. Whether the design of nature in giving the snake this instrument is to enable it to warn other animals and men of the danger of coming too near, or for some other purpose, we can only conjecture.
There is a mystery, too, in respect to its venom. Some have supposed that this venom was given to it as a means of killing its prey before devouring it. Other serpents are endowed with the power of killing their prey by the prodigious force which they can exercise in coiling round the limbs of the animal they have seized, breaking its bones in the terrible gripe which they give it, and thus putting a sudden and total stop to all the vital operations. All serpents seem to require some extraordinary means of killing their prey, for they are formed to live upon animals much larger than themselves, and which they could not kill by any ordinary means.
There is a considerable number of species of serpents with rattling tails in America, but it is singular that there are none of any kind in the old world. The whole tribe of rattlesnakes is an American production altogether.
The Rattlesnake more Sinned Against Than Sinning
Notwithstanding the hatred with which the rattlesnake is regarded and the opprobrium which is cast upon him by man, he seems, after all, to be more sinned against than sinning, for he really is a very quiet and peaceable beast, that has no quarrel with man, and never injures him unless he honestly supposes that he is called to do it in self-defense. If he sees a man coming toward him, he crawls quietly away, if a way of retreat is open to him, If not, and if his enemy still approaches with an aggressive air, he feels himself justified in defending himself by the only means with which nature has provided him. He winds himself up into a spiral coil, with his head projecting from the center of it, and as soon as his enemy comes near, he darts forward and upward, and strikes his fang into his enemy"s flesh, at a point as high from the ground as he can attain.
He Acts Always on the Defensive
He, however, seldom or never attacks man of his own accord, but warns him away by sounding his rattle when he sees him coming inadvertently near. It results from this his peaceable disposition that, though the prairies in the western country, and the forests at the south, are full of rattlesnakes, numbering probably millions upon millions, and the slaves upon the plantations, and the farmers and emigrants and railway laborers in the woods, are continually encountering them, it is very rare that lives are lost from their venom. How great must be the forbearance, we might almost say the generosity exercised by the reptile, to lead to such a result as this!
This generosity, however, if generosity it be, seems to be very little appreciated by man. Man everywhere attacks and kills every rattlesnake that he sees. He strikes him on the neck with a club if he wishes to kill him at a blow; and if, on the other hand, which is more frequently the case, he wishes to tease and torment him for a while before putting him to death, or if he wishes to capture him, he comes with a forked stick, and sets the p.r.o.ngs of it into the ground, one on each side of the poor victim"s neck. He then grasps his neck behind the stick with his hand and takes him up with impunity. It is even possible, while holding him thus, to extract his fang, or the little bag of poison at the root of it, and thus render him entirely harmless.
The Humming Bird
From the rattlesnake, one of the most repulsive of all animals to man, we turn with pleasure to the humming bird, an animal that likewise owes a part of his celebrity to a sound that he makes, though the instrument with which he makes it is a pair of wings instead of a tail. Whatever of mystery there may be about the rattling made by the reptile, there is none in respect to the humming noise made by the bird. The sound is due simply to the rapidity of the vibrations of the wings, and this is due to the smallness of the bird. For the smaller the bird and the smaller the wings, the more rapid must be the motion of them to sustain the weight of the body in the air.
Vibrations Producing Sound
Sound is produced by the vibration of any substance in contact with the air, by which vibrations are imparted to the air, and thus transmitted to the ear. If the vibrations are slow no audible sound is produced. Thus the motion of the pendulum of a clock, the wagging of the tail of a dog, the motion of the hand up and down in the air, as rapid as it is possible to make such a motion, produce no sound.
As we increase the rapidity of such vibrations, however, we at last come to a limit where a sound begins to be heard. This is about thirty-two beats in a second. The humming bird"s wings, therefore, must move to and fro more than thirty-two beats in a second, and it is simply in consequence of the fact that his body and wings are so small that the rapidity of the motion of his wings comes within the limit above referred to, and sound is produced. The wings of a swallow make less than thirty-two pulsations in a second, and thus that bird moves through the air silently.
As the rapidity of the vibrations of any moving body increases the sound becomes higher in pitch. Thus the wings of a mosquito, moving much more rapidly than those of a humming bird, made a more acute sound. As the rapidity increase still more, we reach at last a point where sound is no longer produced. This limit varies with different ears, but with most persons it is at about eight thousand vibrations a second that sound ceases to be heard. This upper limit, however, is extremely vague.
The number of vibrations corresponding with the middle c of a musical instrument, according to the diapason recently established by the French government, if five hundred and twenty-two. That of a sound one octave below is half as great; of one an octave above is twice as great. Thus by finding the pitch of the sound made by the wings of a humming bird, by means of a piano forte or other instrument, the number of vibrations made by them in a second can be approximately ascertained.
The Humming Bird"s Mode of Life
The humming bird is designed, like the bee, to feed on the sweet juices found in flowers. But being a bird, and thus, small as he is, too large and heavy to alight upon the flower and rest his weight upon it, he is provided with wings to poise himself in the air, and a long slender bill to serve as a pipe with which to draw out the juices from the innermost recesses of the largest corollas.
There are a great many different species of humming birds, all peculiar to America. None are found in any part of the old world. There is a difference in the form, and also in the plumage of the different species. In some of them the feathers, especially those of the neck and breast, are splendidly iridescent, glowing with all the colors of the richest gems. Nothing can exceed the beautiful effect of these colors when the bird is seen poised in the sun before the flower from which he is extracting the juices with his long and slender bill. At such a time his wings cannot be seen, so swift is their motion; or if a glimpse of them is obtained, they produce only the effect of a little quivering mist at his sides. He seems like a wingless bird poised motionless in mid air.
If at such a time anything occurs to alarm him or to attract his attention, he darts off through the air a little way, quick as a flash, then suddenly stopping and poising himself upon his wings, he rests as motionless as if he were standing upon the ground. Then, after contemplating for a moment the object that alarmed him, he shoots off again through the air, with a motion so quick that the eye can scarcely follow him--and is gone.
Sometimes artificial flowers are made of the feathers of the humming bird, especially those taken from the breast--the different colors being arranged to represent the different parts of the flower. Nothing can exceed the gorgeous beauty of these imitation.
Gentleness of Disposition
Humming birds are of a very gentle disposition, and they could be easily tamed were it not that they are of too delicate a const.i.tution to bear confinement; and thus, whenever they are brought into the house and shut up in a cage or an aviary, they soon droop and die. While they are thus kept they must be fed with fresh flowers, or else with honey, thinned with a little water.
They build their nests upon shrubs or upon the stems of vines or other climbing plants, nor far from the ground, and the nests are so small that, when seen from a short distance, one of them might very easily be mistaken for a little tuft of moss, or a moss-covered knot upon the wood. There are two eggs only laid in the nest. They are white, and not much larger than peas.
These birds are very common in the West Indies and in all the tropical parts of America. A young English gentleman, who was about embarking for England, happened, just before he went on board his ship, to find a humming bird"s nest with the mother sitting upon it, sitting. He approached very gently to the place. The bird watched him anxiously, but she was too intent upon her duty to her eggs to fly away. The gentleman carefully cut off the branch and carried, it, nest, bird, and all, on board the ship, intending to present his prize to a lady of his acquaintance on reaching his native land.
He fed the bird on home and water during the voyage. She became quite tame, and continued on the nest until the little birds were hatched, but before the end of the voyage she died.
The little birds lived to reach the land. The gentleman presented them to the lady for whom the present was intended. One of them died very soon, but the other lived a month or two, and was so tame that he would put his bill to his mistress"s lips and draw out honey and water from a little supply which she had provided for him there. It was to him just as if her lips had been the petal of a flower.
The Indian Races
Question of the Origin of the Different Races of Men Whether it would seem more probable, judging by the light afforded us by the observation of nature alone, and without regard to the declarations of Scripture, that all the different races of men have descended from one common stock, or that each race had a different origin, and thus now forms a different species from the rest, is a question that has been much discussed by naturalists and philosophers.
In making these inquiries several considerations have operated upon the minds of philosophers to lead them to set out of the case the testimony of the Scriptures. In the first place, some of the most distinguished naturalists and philosophers do not believe in the divine authority of the Scriptures, but regard them simply as ancient writings, of great moral and historical value indeed, but yet not at all of infallible authority on any subject. Others, who believe in the Scriptures as a revelation of the divine will, think that they are intended to guide us only in matters of faith and practice, and that it was not the design of the Holy Spirit, in inditing them, to teach us science and philosophy, but to leave us, in respect to those branches of knowledge, entirely to our own observations and studies in the field of nature itself.
There is a third cla.s.s still, namely, those who think that while every inference which may be fairly drawn, even from the incidental allusions contained in the Scriptures, may be entirely relied upon as a truth revealed to us by divine authority, whatever may be the subject to which it relates, we are not to take these inferences with us, either to aid or restrict us, when we go forth into the field of the world as students of natures, but are to act independently, and avail ourselves of the lights of science and philosophy alone. They think, in other words, that the true object which we should have in view in studying nature is simply to learn what nature herself teaches, and that in doing this we must interpret what we see solely by the light of our reason and reflection. We may distrust the conclusions that we come to, when we arrive at them, if we find that they conflict with convictions obtained in other ways, but in the process of coming to these conclusions we must be guided honestly and entirely by what our observations of nature herself teaches, and by those alone.
Distinction of Races
There are four or five and perhaps many more distinct races of men upon the earth, each separated from the rest by very decided and apparently very permanent lines of demarcation. The differences are not merely those of color, or of any other external mark, but they relate quite as much to the internal organization of the individual, both bodily and mental. These different races are subdivided into many others, all marked by distinctive lines, more or less decisive and permanent. The great question for naturalists to solve has been whether, judging from the light of science alone, without any aid from the declarations of Scripture, we should conclude that all these different forms have descended from one pair.
Now, although, in coming to their conclusion on this subject, philosophers have set the authority of the Scriptures, for the time being, aside, it is remarkable that the conclusion which they have come to corresponds with and confirms the testimony of the Mosaic records; for the whole body of naturalists, with few if any exceptions, have concurred in the opinion that the differences between the various races of men, great as they are, and permanent as they seem to be within the periods subject to our observation, are not specific differences--that is, that they are not such as, judging from observations made in other divisions of the animal world, imply a separate original parentage. In other words, that there is nothing in them which should preclude the idea of their all being descended from a single pair.