of the nose and of the Eustachian tubes, and so prevents the food from returning through the nose, which sometimes happens partially in drinking. Moreover, in the act of deglutition, the larynx, which being composed of cartilaginous rings, in its ordinary state compresses the esophagus, is carried forwards and upwards by muscles destined for the purpose, and consequently dilates the opening of the gullet. On reaching the gullet, the food is carried down by the principle of gravity: and a mechanical contrivance also lends its aid. The muscular fibres of the œsophagus contract from above, and press the aliment forward to the stomach. This is obvious in drinking with the head downwards, when deglutition can be performed by the muscular action of the œsophagus only.

The food soon reaches the stomach, a membranous bag, or dilatation of the alimentary canal, where it is accumulated and undergoes new processes. In its process towards the stomach the food is broken and divided by the teeth, and attenuated by the saliva, a powerful solvent. On reaching the stomach it is subjected to the operation of a new chemical agent, the gastric juice, a liquid secreted chiefly by that organ. The nature of this liquid is not yet fully known. Its taste, colour, and solvent powers are different in different classes of animals. Some living creatures cannot digest that which is the food of others. Some animals, such as sheep, live wholly upon vegetables; their stomachs do not digest animal substances. Others, as the eagle, feed entirely on animal substances: their stomachs do not digest vegetables. Hemlock is poisonous to man; but goats eat it without injury.

The gastric juice does not continue always of the same nature, even in the same animal. It is in some measure modified according to the age, the health, the habits, and the different aliments on which the animal subsists. Sick persons and children are incapable of digesting the food which is nutritious to a healthy man. Some graminivorous animals may be brought to live on animal food, and to reject grass; and some carnivorous animals may be accustomed to vegetables. But still the gastric juice, although it in some measure accommodates itself to the substances subjected to its operation, evidently appears to have peculiar qualities in certain classes of animals. In the dog it dissolves hard bones, but, in equal times, makes no great impression on potatoes, parsnips, and other vegetable substances. On the other hand, in the sheep and ox it speedily dissolves vegetables, but makes little impression on animal bodies. Different tribes of animals are distinguished by their gastric juice as well as by their exter

nal form, and both are well suited, in every instance, to the habits of the creature; for in many cases there is an astonishing correspondence between the teeth and that liquid. The teeth of graminivorous animals are differently formed from those of the carnivorous tribes; and in both they are wonderfully suited to the food and to the gastric juice of the animal. He who can believe that all these adaptations are the result of chance is no enemy to credulity.

The gastric juice, while it dissolves food, even although enclosed in perforated metallic tubes, spares the living stomach. But, when life ceases, this liquid often acts on the very organ from which it has been secreted. It differs from a chemical solvent, in having an assimilating power, by which it reduces all substances, whether animal or vegetable, into a soft pulpy mass named chyme, and prepares them for passing from the stomach into the intestines. If the food has been properly digested in the stomach, on reaching the lower orifice of that organ, named pylorus, it is freely allowed to pass. But if it is not fully reduced to chyme, then, by a sort of instinctive sensibility of the pylorus, it is thrown back into the stomach to undergo more thoroughly the action of the gastric juice. In the intestines, the chyme is mingled with the bile and pancreatic juice. In short, from one extremity of the alimentary canal to the other, fluids are perpetually flowing into it from the glands and other sources. By the action of these fluids, and of the intestines, the chyme is formed partly into chyle, which is absorbed by the lacteals, and thrown into the circulation, and partly into excrementitious matter, which is ejected from the body.

Here then we see an astonishing process carried on by the instrumentality of many different parts, all nicely adapted to each other, all co-operating in the same work, and tending to the accomplishment of the same end; the support and nourishment of the body. The mastication and deglutition of the food, and the moistening of it with the saliva before it enters the stomach; the great change which it undergoes in that organ, chiefly by means of the dissolving and assimilating action of the gastric juice; the changes induced upon the aliment after it passes from the stomach; the separation of chyle from the excrementitious part; the absorption of the chyle by the lacteals, which throw it into the blood; the mysterious process of assimilation; the peristaltic motion of the viscera; the mucus which is continually secreted for their protection against the acrimony of their contents; and the ejection of the excrementitious matter from the body; these, when all taken

together, exhibit an astonishing process. undeniable proof not only of design and admira but of great benignity also. What an amazi the body of Man! How wonderful the absorb latory, secretory, and excrementory apparatus system! We are wonderfully made, and the m As of wisdom and goodness are deeply impressed on every part of our frame.

an

To sum up all, on this part of the subject, in a few words; let any person contemplate the human body; let him attentively examine the skeleton, the figure and structure of the bones of which it is composed, with their articulations; the muscles, their origin, insertion, strength, and action; the organs of sense, the eye, the ear, the nostrils, the tongue and palate, and the sense of feeling diffused over the whole body; the structure of the jaws, the stomach, and other viscera ; the structure and action of the lungs, and organs of speech; and if he can retire from the examination without a deep impression of intelligence and design, yea of wisdom and goodness, in the human frame, there can be but little doubt that his understanding is singularly obtuse, or his heart singularly depraved. Every mind, open to the force of evidence and to the impressions of truth, must join in the exclamation of an ancient sage, "I am fearfully and wonderfully made."

It may here be remarked, that as food nourishes the body, so sleep refreshes both body and mind. This mysterious phenomenon we are unable to explain; but its periodical return is necessary to life, and by it a beneficial end is accomplished. There is an obvious relation between sleep and the rotation of the earth on its axis. They are harmonious parts of one whole.

CHAPTER IV.

THE INFERIOR ANIMALS.

MAN is evidently the noblest inhabitant of the earth. He is not, indeed, so strong as the elephant, nor so swift as the antelope; his eye is not so piercing as that of the eagle, nor his sense of smell so exquisite as that of the dog: but the high faculties of his mind give him superiority and dominion over the whole animal creation. Around us we see a vast

variety of objects, possessing very different qualities. These objects do not stand at a great distance from each other: they are wonderfully linked together, rising above each other by almost imperceptible degrees. The system of nature is a system of insensible gradations. The two extremes of organic and inorganic matter, perhaps, meet at a common point. Corals and corallines seem to unite the mineral, vegetable, and animal kingdoms. The boundaries of animal and vegetable life are obscurely defined, and the interval between the polypus and man is filled up with an amazing gradation of animated beings. The progress from unorganized to organized matter, from vegetable to animal, and from animal to rational existence, presents an astonishing and graduallyascending series. In the whole progression we see a striking uniformity of plan, with a rich variety in the execution: beautiful analogies and nice distinctions everywhere occur.

It is animal existence which, at present, claims our attention. The earth, the air, and the water, are all abundantly replenished with sentient beings, differing in their external appearance, their habits, and their dispositions; and all enjoying happiness according to their several constitutions. Man unquestionably stands at the head of this system of animated being; and there seems to be a much larger interval between him and the most sagacious of the inferior animals, than what occurs in any other part of the gradation. It is true, indeed, that in a number of instances, we find man in a state little superior to that of the brutes: but, in the view under consideration, we must take his capacity of improvement into our estimate. My full conviction is, that if we were to examine animals in every gradation from the polypus to man, we should meet with incontrovertible evidences of design, and wise and benevolent contrivance, in every stage of our progress. But a field of this kind is greatly too extensive for our present purpose. It would be, no doubt, both pleasant and instructive leisurely to pass through the whole animal kingdom, and to examine with minute attention everything that fell in our way. This, however, would lead into voluminous details, instead of a concise treatise. My limits confine me to a few remarks; and as neither comparative anatomy nor natural history is my object, I shall pay no attention to systematic arrangement, but shall endeavour to show,

I. That the form of the inferior animals is admirably adapted to their manner of life.

II. That they are provided with suitable clothing.

III. That they possess means of defence suited to their condition.

IV. That they are qualified for procuring their food.

V. That we meet with surprising adaptations of animals to peculiar circumstances.

VI. That each kind is capable of continuing its species.

Under each of these heads, I shall mention a number of particulars respecting the inferior animals: these particulars will be of a very miscellaneous nature; but, I presume, will all tend to show wise design and benevolent contrivance in

nature.

I. The form of the inferior animals is admirably adapted to their manner of life.

1. In the form of the different kinds of quadrupeds there is great variety; but amidst all the variety we perceive the same general plan; the same great outline appears in the skeleton, in the articulations of the bones, in the disposition, form, and insertion of the muscles; and in several other circumstances, all accommodated to the peculiar nature and habits of the animal. The organs of sense, of digestion, of circulation, and of generation, occur in all the species, but are varied according to the destination of each.

In order to support the head of quadrupeds, they are furnished with a very strong ligament firmly bracing the head to the vertebræ of the back. This ligament arises from the spines of the dorsal and cervical vertebræ, which are lengthened out for that purpose, and is fixed to the middle and posterior part of the occipital bone. It is of great strength and size in all quadrupeds; but is remarkably so in the elephant, where the great weight of the head requires a strong support. This ligament is wanting in man, because he did not need it; but it is of great use to quadrupeds, and they are provided with it. Here, as in every other department of nature, the provision is suited to the exigency of the case.

In graminivorous animals we see a remarkable correspondence between the length of the legs and the length of the neck. According to the ancient fable, Tantalus was set up to the chin in water, and apples were at his lips; but he had no power to stoop to the one to quench his thirst, or to reach up to the other to satisfy his hunger. There is nothing like this in nature. All animals are capable of gathering their food. Herbage is abundantly provided for the graminivorous tribes, and there is such a correspondence between their necks and their legs that they can easily reach it.

2. The external figure of birds is excellently adapted to