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On every account, and in every station, it will be found, that those characters will be most honourable in themselves, and beneficial to society, over whose minds religious principle has a fixed dominion, and who are studiously careful to adjust all their actions, public and private, personal and social, according to the unerring laws of revelation.

But this is not a directory to be picked up by chance, or that may be adopted at any period with the same facility as matter of ordinary intelligence. It is the science of life, and must, therefore, be taught in the spring-time of youth, while the natural reverence for virtue is unsophisticated by the allurements of error, and while the mind is in a proper state to receive the impressions of truth.

Let it be considered also, that religion is a growing science, and expands with every advance made in morals, policy, or natural knowledge. The wonders wrought immediately by its Founder were adapted to the particular observers of those miracles, and the age when they were performed; but we, upon whom the ends of the world are come, have a surer testimony in the prophetic word, which is continually receiving confirmation from the changes that are taking place among the nations of the earth. It is a question, whether that man is most to be pitied or despised, who can contemplate the mighty revolutions which have been, and still are, disturbing the political hemisphere, without discerning and admiring the divine agency in disposing those events to the accomplishment of the sacred predictions. The history of the world for the last forty years, has been a running commentary on the prophetic scriptures, and every new scene evolved in the great drama, has proved an additional instrument in that complicated scheme of moral government which human wisdom can neither retard nor promote by any device or combination. The oracles of inspiration, however dark and mysterious they may have originally appeared, are now unfolding and becoming clear in their connexion with passing events, so that the simplest understanding may be convinced

Yet amidst this blaze of light, many chuse to walk in darkness; and though they have a guide that cannot mislead them, they prefer to such a sure standard, the feeble and wavering principle of natural reason. Confident in an imaginary independence, they lay claim to extraordinary sagacity, and affect an uncommon zeal for the advancement of human science and general literature, as if such attainments constituted the basis of individual happiness, and national prosperity. Though these ingenious spirits may not in direct language deny a creative power, they in reality exclude the Divine Author from the moral government of the world which he has made; and by exalting human knowledge to excess, they weaken in the minds of men that reverence for the authority of divine truth, which is necessary to the observance of its precepts. Hence it is not to be wondered, that a spirit of scepticism should be generally prevalent, when we have seen in our day a wide departure, among men of science, from the fundamental principles of religion. In France this was notorious, and two of the ablest philosophers and astronomers of that country, Condorcet and Lalande, to say nothing of others, made an open profession of atheism. Most of the physiologists of that nation, and many in our own, have asserted, that the entire organization of man is material, and that there is nothing of a spiritual nature in his system. Some anatomical lecturers have, in coarse language, thrown out reflections upon the Mosaic history of the creation, for the edification of their pupils; and there have been geologists who have ventured to assert, that the globe which we inhabit, if not eternal, must have had an origin many ages anterior to the æra commonly ascribed to it on the credit of the sacred history.

To enumerate the various modes in which scientific inquiries have, of late years, been pressed into the service of infidelity, would swell this essay to an immoderate extent. Even in morals, the same spirit of innovation has been manifested in elaborate treatises, purposely written, to set aside that system of practical virtue, which has for successive generations, constituted the basis of all legislation. According to these reformers, what have hitherto been cherished and cultivated as social affections, are merely artificial, and repugnant to natural freedom. Hence, concubinage has been openly justified, and filial duty treated

with ridicule, not by professed libertines in idle romances, but by men of studious babits, calling themselves philosophers, in volumes, having for their object, if we are to credit their writers, the amelioration of society.

When all this is considered, and more might have been taken into the account, the danger of relaxing moral discipline, and of setting aside religious instruction in places set apart for education, must be obvious to every one that has any regard for the public welfare. Much is expected from the extension of science; but if piety does not sanctify the advancement in knowledge, there is reason to fear, that a generation so raised will not easily be kept in order by the mere authority of human laws.

ESSAYS ON PHYSIOLOGY, OR THE LAWS OF ORGANIC LIFE.

(Continued from col. 355.)

ESSAY VII.-On the Circulation of the Blood.

IN one of our preceding essays, a brief description of the chemical properties, and constituent parts, of the blood, was given, and the change also explained which it undergoes in the lungs; there is, however, another property belonging to it, which we have as yet omitted to mention, and which, because it is disputed among physiologists, has been reserved for this place, in order that the reasons may be more fully stated on which the doctrine is founded,-we allude to the vitality or life of the blood.

That the blood possesses a principle of vitality, we cannot, for ourselves, a moment doubt; for it would appear contrary to the rules of nature, that a fluid, which, had it not this principle, might be considered as an extraneous mass, should be the preservative of life, and the nourishment of the system.

With the nature of the vital principłe we are totally unacquainted,-we only recognize it by its effects. One of these is, the power which it imparts to the animal frame, of resisting putrefaction, to which, if unendued with this principle, it would be liable; and another is, the preservation of every part in that state by which it is enabled and fitted to perform its destined office. For instance, we know that the blood when removed from its natural reservoirs soon coagulates, or rather separates into two parts, one of which becomes solid. Why does not this process

113.-VOL. X.

take place in the vessels also? To us it appears connected with that principle of vitality, from the loss of which its nature becomes changed-it coagulates, and its component parts undergo separation.

But it may be objected, that the blood, when taken from the body, undergoes this change from other causes; as from cold, from contact with the air, or from the want of motion. If we examine each of these objections separately, we shall, I think, find them in a great measure groundless. It must be allowed, that we are in general most acquainted with, and accustomed to behold, the blood of the more perfect animals, whose temperature commonly exceeds that of the surrounding atmosphere; the blood, therefore, of such animals naturally cools and coagulates at the same time, from which we are led to assign that as a cause, which is only a concomitant cir

cumstance.

The celebrated John Hunter, by whom the vitality of the blood was strongly advocated, relates the following fact, which he himself ascertained by actual experiment ---If we take (says he) a fish out of the sea, the heat of its body being perhaps about 60°, and bring it into an atmosphere of 70°, the blood on being let out of the vessels will immediately coagulate; now, here we see that the blood became of a warmer temperature than natural, and yet coagulated. Besides, if cold would produce this effect, we should certainly find it in those instances where the temperature of various parts has been reduced nearly to the freezing point, as often happens in the fingers, ears, &c.; but this does not appear to be the case; nay, the blood of animals has been frozen in the vessels, and thawed again, and still its fluidity remained unaltered. Blood, when drawn and quickly frozen, before it has time to coagulate, returns again to its fluid state on being thawed, and THEN coagulation begins as usual.

From these circumstances it appears plain, we think, that cold has no influence in producing this effect. Let us then investigate what the contact of the atmosphere may occasion. That this cannot be the cause is easily proved; for it is found, that blood coagulates much more rapidly in a vacuum, as under the exhausted receiver of an air-pump, than in . the usual circumstances; and we may observe also, that the blood, when extravasated from the vessels into the skin or cellular membrane, still undergoes this change, although it is impossible that the air should have been in contact with it.

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their healthy state allow the coloured particles of the blood to pass through them, but only the most subtle part of the serum, which, by their own agency most probably, they separate from the circulating fluid. Some indeed have imagined, that this separation between the constituent parts of the blood takes place spontaneously, uneffected by the specific agency of these vessels. This, however, cannot be allowed, as it regards the exhalants of the skin and simple membranes, as the pleura, unless it be proved that every secretion, however it may differ from the blood, is a spontaneous separation also. Besides, this supposes a continuous rest from motion; whereas the blood is in a state of constant progression, volume hurrying after volume upon every pulsation. There can, we think, be but little doubt that these vessels, as well as the rest of the same class, really secrete, or separate from the blood, whatever it is requisite should be expelled from the system.

The minute arterial ramifications (not ending in veins) have all their appointed secretions to effect and deposit, as bone, fibre, &c.; and it is somewhat singular, that every secretion, with one exception, should be the result of the agency of the arterial system. This exception refers to the bile, which we have previously mentioned as produced from venous blood, and which we now state to be effected through the agency of venous capillaries. There is, however, a case upon record, in which this rule was violated. In the instance alluded to, the venæ portæ, or large veins of the liver, were wanting; an arterial branch, preternaturally increased, assumed in a certain sense their office; and the secretion of bile was effected from arterial blood, and differed in no respect, in observable qualities, from the fluid as usually secreted.

By secretion is to be understood, that property which certain vessels or organs possess, and by which they are enabled to prepare, and separate from the blood, a substance essentially differing from itself, and which, in general, is not to be previously discovered in its composition. Thus secretion is not confined to a mere separation only, of one of the constituent parts of the blood, but supposes, in fact, a real conversion of it, or of a constituent part of it, into a new substance, prepared immediately by these vessels; and it may be further observed, that the more dissimilar the secretion to the blood, the more complex is the vascular apparatus adapted for the purpose of secreting it. That we may be here the better understood, it is necessary to

explain, that many fluids require for their secretion organs more complicated in their nature than the exhalent tubes, (which secrete a fluid by the agency of a simple organization, but little differing from the serum of the blood.) Such organs are that order of glands termed conglomerate. These glands are not to be confounded with those of the lymphatic or absorbent system which we have before mentioned, and which are called conglobate.

As it respects the glands adapted for secretion, the arterial ramifications, it is true, are the agents by which the operation is carried on,-but it would appear, that from their arrangement and disposition, their modes of action become peculiarly modified; and as in each gland this arrangement differs, so also the mode of action differs, and hence different fluids, as the results, are secreted. The conglomerate glands are composed of nerves and vessels of all kinds matted together in bundles, by means of a cellular tissue, but exhibiting a difference in structure, according to their respective offices, and peculiarities of action. From each gland arises sometimes one, sometimes several ducts, for the transmission of the secreted fluid to the part or organ naturally requiring its presence.

If we glance over the operations which the vessels of secretion have to carry on, we shall be astonished at their number, complexity, and importance. In fact, the whole frame, all that composes it, is the result of their labours; and hence organized bodies have been compared to the chemist's laboratory, in which, by numerous agents actively employed upon the same material, the most curious changes, composition and decomposition, synthesis and analysis, are all carried on. We must not, however, lose sight of the power by which these agents are enabled to execute their respective functions; namely, that to which we have applied the term latent sensibility.

The organs of secretion are supplied by nerves arising principally from the great sympathetic, and which terminate in their substance, giving to each of them that peculiar faculty by which they are enabled not only to discover in the blood that constituent part requisite for the purpose needed, and separate it from the remainder, but also to convert it more or less completely into a new substance. Thus the organs of secretion appear to possess two properties, certainly distinct, although dependent upon each other,—a peculiar tact, by which they discover and separate the required elements; and a power so modifying those