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what a graminivorous animal of even a portion is called the chyle. When the food smaller bulk would require. Hence we has entered the stomach, it becomes mixed may conclude, that all substances, before with saliva, and the gastric juice. By the they become fitted for the nutrition of the agency of these it becomes converted into animal race, must undergo a peculiar an uniform pulpy mass, to which the change and modification; in fact, become nanie of chyme is given; but it is not yet organized ; and that in the flesh of animal fitted for the system; it now passes through bodies, the relative proportion of nutriment | the pyloric orifice of the stomach into the is greatest.

duodenum, (a portion of intestine,) and If this be the case, that all matter, before becomes there mixed with the pancreatic it be fitted to support animal life, must itself juice and bile. The pancreatic juice is a have been immediately in a state of previous Auid prepared by a gland termed the panorganization, it may be asked, Does not creas, the bile by the liver. By the action the vegetable world also follow the same of these fluids on the pulpy mass, a comlaw? No: The great Author of the uni plete conversion is effected, and that portion verse has so constructed the vegetable fitted for the purposes of the animal ecotribes, that they are enabled to convert the nomy is, as we have said, termed chyle. particles of inorganic matter into organic If we examine the state of these minute bodies; to assimilate various earths, water, tubes or vessels in an animal recently killed, and air, which, becoming parts of them and before the vital warmth is extinguished, selves, undergo, as it were, the first stamp of we shall see them (at least if the animal organization, and enter upon their career of has been lately fed) filled with a milky vitality; the soil, however, necessary for fluid, from whence they have their name the growth and nutrition of many plants, lacteals : this milky fluid, which they condoes indeed contain a great proportion of tain, is the chyle. decomposed animal or vegetable matter : The lacteals having thus absorbed this but this forms no objection; for, in the first nutritive portion of the food, after commuplace, animal or vegetable bodies lose by nicating freely with each other, pass through putrefaction all claim to be considered as certain glands termed mesenteric, where organized; and, in the second place, it the chyle appears to acquire new properwould appear, that it is by the peculiar ties. Emerging from these glands, the gases arising from such decomposed matter, lacteals carry the chyle onwards, till they that vegetables are nourished; whereas enter, at last, into the thoracic duct, a vesanimals require recent vegetables or animal sel which passes along the spine, and pours matter, for their support. Thus does it the chyle into a large vein, almost immeappear, that one of the purposes for which diately entering the heart, termed the left the vegetable kingdom is designed, is to subclavian vein ; here it becomes mingled form a vast laboratory, in which various with the blood. It has not yet, however, lost inorganic substances are to be prepared for its character; but after passing through the the use of the animal world, by effecting heart, and thence through the lungs, it upon them a necessary peculiar and most becomes incorporated with the rest of the wonderful change; a step preparatory to a blood, from which it is no longer to be new change as wonderful—for a particle of distinguished. matter, originally unorganized, may become There is, however, another set of vessels, a portion of the grass which covers the which, as well as the lacteals, terminate in meadow,-of the ox which grazes upon the thoracic duct, and contribute likewise it,-of man, the lord of the creation,-and to the repair and preservation of the system. when he moulders in the earth, return to its Throughout every part of the frame, in original state, and again become incorpo the interior as well as on the surface, are rated in plants, to run a new career. | distributed innumerable vessels, destined to

It has been stated, that the animal frame absorb and carry into the blood the superowes its existence and growth to the appro fluous fluids of the body, as well as all priation and assimilation of fresh particles, substances immediately within the sphere of which become identified with the rest of their action. External bodies are not the the body; let us explain how this is only ones on which they act. On the effected :-Proceeding from the inner sur structure of the frame itself their operations face of the stomach and the intestines, are continually carried on; for it must not numerous small tubes or vessels are ob be forgotten, that the organized living maservable, whose office it is to separate and chine is undergoing a double set of internal absorb or take up the nutritive particles of operations, its destruction and renovation; the food, as prepared by the digestive and whatever comes off in the constant organs for their reception : this nutritious I wear of this machine is taken up by these

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Essays on Physiology: Essay IV.

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vessels, the absorbents, or, as they are ters, and by different routes, for the same called, lymphatics, from the limpid fluid | destined place; the whole, however, comwe always observe them to convey.

municating largely with each other. · The minute tubes which form the com In various parts, and for reasons not mencement of the lymphatics, are furnished | fully known, companies of these absorbents with orifices so small as to be totally imper, form themselves into masses of convolutions, ceptible to the naked eye; and each orifice, differing in number and magnitude, and inendowed with the power of contracting or termingled with a similar congeries of blooddilating, absorbs or refuses, according to | vessels. These masses are the glands, the peculiar impression produced by the observed in the neck and other parts,) the object in contact.

uses of which are not, as yet, fully ascer- In what manner the lymphatics, and tained, although it is most probable that indeed the whole absorbent system, propel some change is effected by their agency on or convey the fluids they contain, is a the lymph, by which it is rendered more fit question on which physiologists have enter for the purposes of the animal frame; and tained very different views; some, for in- | this would further appear, from the increased stance, and these eminent men, have as tendency to coagulate, which it manifests serted it as a fact, that they circulate | after passing through the glands, (which it through and ascend these minute tubes, does slowly, as if impeded by the way,) as contrary to the law of gravitation, not from well as some alteration in its appearance. any propelling power in the tubes them- At the same time, however, it must be selves, but by that principle which causes observed, that the real nature of the lymph the ascent of liquids through tubes of great / is far from being well understood. By minuteness, termed capillary attraction. some it is considered as analogous to the To this opinion, however ingenious and serum of the blood, which is indeed the apparently satisfactory, there are many opinion of Hâller, who often gives the strong objections: for were it correct, we | name of lymph indiscriminately to the fluid might expect that neither age, nor sex, nor of the absorbents, and to the serum of the temperament, nor habit, would produce the blood. least variation or irregularity in the absorb- From the circumstances attending the ing power, and that all would proceed production of the lymph, we might be led with uniformity. But this is far from being to judge, that its nature and component the case; for as much so as every vital | parts would be subject to variety and function, the action of the absorbents is change; and this is found to be the case; liable to irregularities inconsistent with the but in the chyle these differences are still theory just mentioned. Indeed it is much more evident, arising from the various subto be doubted, whether any of the functions stances used as food. Indigo, madder, and of organized bodies, on which their vital beet-root tinge it with their respective hues. existence depends, are to be accounted for It is, however, as we have said, in general upon purely mechanical principles; a sup. white, slightly viscid, and much resembles position which has led to theories very milk. When removed from its vessels and ingenious, but unfortunately erroneous. exposed to the air, it separates into two

It appears more possible, according to parts, viz. fibrine and serum ; and the lymph our ideas, that the absorbent vessels are also, under similar circumstances, undergoes endowed with a sufficient power of carry. | the same change. ing on or propelling the fluids they contain, Both the lacteals and lymphatics termiby some peculiar action in themselves, nate in the thoracic duct, which empties its which they are enabled to exert so as to contents into the left subclavian vein. At the answer the end in view.

point of junction between these a valve is The lymphatics, after arising from various placed, so constructed as effectually to preparts of the frame, the surface as well as vent the blood from finding its way into the the interior, by minute tubes in close con. thoracic duct, but which offers no impeditact, unite and divide, and so interminglement to the exit of the chyle. with each other as to form a close network, From this source then the blood receives which, with a similar tissue of nerves and its supplies, and nothing can incorporate blood vessels, forms the cellular and inem- with the system, or be received into it, braneous textures of the body. Emerging without proceeding through this channel. thence, and proceeding onwards, they form Having now conducted the nutriment distinguishable trunks, and again enlarge through its various stages, till it enters into by the union of others; and multitudes of the blood to supply the continual drain these run together a parallel course, forming upon this reservoir of vitality, we shall folcompanies proceeding from different quar- low up the subject, and proceed to give a

........iconrrarmır.....roopa more detailed account of that most beauti- | called the tuberculum Loweri. Within the ful and interesting phenomenon of the auricles bundles of muscular fibres project animal frame, the circulation of the blood from the sides. These, from their resem· The circulation of the blood is an opera- blance to the teeth of a comb, are termed tion immediately connected with our ex- musculi pectinati. The partition between istence, and on which it depends; and will the right and left auricle is called the it not excite our astonishment, that two septum auricularum. centuries have scarcely elapsed since its | The right auricle communicates with the laws have been at all correctly ascertained ? right ventricle by means of an opening, and even now, many points are disputed, denominated the ostium venosum ; at the and enveloped in obscurity. We may with edges of which, within the ventricle, are safety conclude, that the ancients were in three valves, or rather a valve divided into almost total ignorance respecting the real three parts, called the tricuspid valve, from nature of the circulation, or the mode in its resemblance to the points of three which it is performed; for although, per- spears; to the edges of this valve small baps, among their writings, passages may muscular bundles are attached, called car. be found apparently indicating some ac-neæ columna, by means of tendinous quaintance with the subject; yet as they chords, (chordæ tendina.) From the right have left us no distinct account, and as ventricle the pulmonary artery arises, at their works abound with gross absurdities the root of which, internally, are situated respecting it, our conclusions are certainly the three semilunar valves, with a small warrantable; especially when we consider white body at the edge of each, termed at the same time, how little anatomy was corpus sesamoideum. Into the left auricle cultivated as a science among them.

the four pulinonary veins enter. The coats The discovery of the true nature of the of this auricle are thicker than those of the circulation is due to Harvey, who flourished right, otherwise it exhibits much the same in the 17th century ; but since his time, appearances. It opens into the left ventrisucceeding physiologists have diligently cle, having also at the opening a valve, applied their talents to the subject, (a wide but divided only into two parts, called, from field for investigation,) and have added by its likeness to a mitre, valvula mitralis. their labours many new facts to the disco- | The great difference which the left ventricle very of their immortal predecessor.

exhibits is the superior strength and fleshi. Various and important are the uses which ness of its walls, indicating the vigorous the circulation of the blood is destined to action it is destined to maintain ; emerging serve :-by its means the various secretions from it is seen the aorta, or main artery, are performed, the growth of the body with three semilunar valves internally at its promoted, and its decay and losses re- root. The use of the various valves we paired; and besides all this, it is, in some shall explain when considering the course mysterious manner, connected with that of the circulation. inexplicable subject, the animal tempera Having thus briefly described the general ture.

anatomy of the heart, we shall next proceed We shall in the first place, then, endea to examine the properties and constituent vour to give a general sketch of the anatomy parts of the blood itself. The blood, when of the heart, the great agent of the circula- drawn from the body, and suffered to tion; and then explain the nature and con- remain in any vessel, quickly separates into stituent parts of the blood-the fluid of two parts,-one a thick yellow Auid called vitality.

serum, the other a tenacious solid mass of a The heart is a large hollow muscle, | dark red colour, termed crassamentum. situate in the chest, between the lungs, and The relative proportions of these vary exenfolded in a bag called the pericardium, | ceedingly, according to age, sex, temperathe inner lining membrane of which is re- / ment, mode of life, &c.; yet generally flected over the surface of the heart itself. speaking, the estimate may be made as ten The heart is divided internally (we are of the serum to fourteen of the crassamenspeaking of man) into four cavities ; the tum. The serum contains water, albumine, right and the left auricle, and the right muriate of soda, and potass, phosphate of and the left ventricle. Into the right soda, animal matter, &c. auricle, two veins, called the vena cava, The crassamentum is divisible into two enter; one bringing the blood from the parts, fibrine, and the colouring particles of upper, the other from the lower parts of the the blood. The component parts of fibrine body. The two veins unite at their entrance are carbon, oxygen, hydrogen, and azote. into the auricle, and at the point of union When the colouring matter of blood rebetween them, a thickening is to be seen, l cently drawn, is examined with a microscope,

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it is found to consist of globules of extreme | sion and worldly feeling arises a system of minuteness, of a red colour, but varying | unfaithfulness in preaching. from different causes, being paler from Perhaps few questions have received illness and deficiency of nutriment, more more varied answers than this: What is florid if exposed to oxygen, and darker if Gospel Fidelity? If I may be allowed to exposed to carbonic acid or hydrogen. define it, I would say, It is to preach the The colouring matter has been said to con- truth, the whole truth, and nothing but tain oxide of iron; this, however, later che- | the truth.It is “ to declare the whole mists have disputed, and Dr. Wells, in his counsel of God, giving to each doctrine its « Observations and Experiments on the relative prominency, to each precept its Colour of Blood,"* after much investigation, proper situation, to each promise its true decides against the theory; indeed, his application, to each threatening its due arguments, which are too extended to be authority, and to each sentiment its legitihere introduced, seem to settle the point at mate and consistent meaning, without fearonce, confirmed as they have been by sub ing the frown, or courting the smile, of sequent inquirers- Berzelius, Brande, and man.” But, is this system uniformly Vauquelin. Mr. Brande has even suc. adopted by all who bear “ the vessels of ceeded in dying cloth with it, but he found the sanctuary?” Some sermons are so considerable difficulty in fixing the colour; enveloped in the flowers of rhetoric, and so the most effectual mordants he discovered adorned in the meretricious trappings of were, the nitrate and oxymuriate of mer human eloquence, that the simple grandeur cury.--The specific gravity of the blood is and the native beauty of the gospel are estimated at 1050, water being 1000. totally lost amidst their cumbrous load of Hammersmith. W. Martin.

worldly ornaments. The faithless minister

studiously avoids all practice, to please the (To be continued.)

Antinomian; or neglects all doctrine, lest he should offend the Pharisee;—such a

man is not only unworthy the name of a ON MINISTERIAL FIDELITY.

“ parson,” but is an actual disgrace to a Human nature is so constituted, that good

Christian community. can neither long exist, nor extensively exert The preaching of the gospel is of too its influence, without being alloyed with

sacred a nature to be made the vehicle for evil, and clogged with sinful infirmities. human applause, or the instrument of a All Christians must necessarily rejoice at

vain ambition. The work of a minister is the vast increase of pure religion, and at connected with all that is important in the dedication of wealth and talent for the time, and with all that is awful in reference advancement of divine truth, and at the to'eternity. It is the work for which the co-operation of mental and physical ener- world was created, for which the Son of gies in the cause of our Redeemer, which God died, for which the Holy Spirit decharacterize the present day : but our joy / scended, and for which the universe exists. is inseparably connected with sorrow. We Its 'connexion with the immortality of the see that persecution no longer exalts its soul, stamps upon it a sacred reality, and hideous and infernal visage, and that the invests it with a fearful responsibility. A disgrace formerly attached to a profession / pulpit is the last place on which self should of religion, is now removed; and that

be exhibited, or in wbich pride should be common decency, and the customs of the

fostered, and a minister is the last man country, prevent many from embracing a

who should offer his adorations at the altar system of infidelity, or following a course

of popularity ; yet, if he be endued with of profanity, and cause them to make some

talent and learning, he is in great danger of show of religion. We rejoice at these bowing the lowest, and of continuing the signs, and hope that they are the harbingers longest, as the infatuated victim of a dread. of more glorious days; but there are cer

ful delusion. It is to be feared, that many tain evils either connected with them, or

a minister has offered more devotions at resulting from them. When religion be this shrine, than prayers in his closet for the comes fashionable, we are in great danger

divine blessing." He has chosen his subof sinking into a fashionable religion; and

ject, selected his text, divided his sermon, wherever there are professors of this fash

arranged his thoughts, and adjusted his exionable religion, they must have fashionable

pressions, under the influence of popularity. preachers, and a fashionable gospel ; and He has forgotten, that he is to draw the from this amalgamation of religious profes

sword of the Spirit manfully and fearlessly,

not to admire the brilliancy of its shape, or + Phil. Trans. vol. lxxxvii. p. 429. to display the splendour of its appearance,

but he is to use it, to wield it with ener- the hypocrite must not be exposed, nor gy, and so to plunge it, that it may “ stick the secure be aroused, nor the profane be fast in the hearts of the king's enemies." If admonished, nor the careless be alarmed ; he neglects this, he should have suffered it they must not be told, that the curse of to remain in its scabbard. To such an Jehovah hovers over them, and that the damone it may properly be said, Where is nation of hell awaits them, if they die in a Fidelity? Where is that feeling which in- state of impenitency. Terms more polite, duced an inspired apostle to exclaim, “I and expressions less severe, must be adoptam clear from the blood of all men ?ed; but when the gospel truckles to human

Popularity is a poor exchange for faith- prejudice, or accommodates itself to sinful fulness, and it often happens that the tumul- opinions, it ceases to be the gospel of God, tuous acclamations, and the noisy plaudits, and becomes a compromising system of of a mixed assembly, are soon turned into man. deadly. hatred and malevolent vituperation : Did St. Paul suit his doctrines, or adapt those who were the first to cry “ Hosanna,” his language, to the philosophic infidelity are the foremost to exclaim Crucify of the Athenians, or to the classic elegance him.” Where can be the piety, or rather of the Romans, or to the prejudiced notions to what an extent does the want of piety of the Jews, or to the abandoned profligacy influence that man, who can calmly see his of the Gentiles? Hear him at Corinth, the hearers sink to perdition, whilst he is busily seat of learning and the nurse of science, occupied in so arranging his words as to exclaim, “ I came not to you with excelmake the offence of the cross to cease, and lency of speech, or of man's wisdom, deto avoid uttering harsh expressions “ in ears claring unto you the testimony of God.". polite;" instead of plainly declaring what Attend to him before Felix,~he is neither the Holy Ghost declares respecting the state awed by the pomp of the judge, nor inof sinners, and instead of pointing them to Auenced by his own personal danger as a the Lamb of God, as the only refuge from prisoner,-he fearlessly tells an incestuous that doom which inevitably awaits them, if man of “ temperance,” and an iniquitous they reject his atonement? But he is too judge of " righteousness," and boldly much engaged in elevating self, to lift up points him to a “ judgment to come,”. Jesus Christ.

where all his bribery would be exposed, and Attend to the ministrations of our Savi all his abominations and injustice be made our; “ the common people heard him known before an assembled universe. gladly,” and they will hear nothing gladly, Faithful ministers are scarce, and those except they understand it: they may bewil- who have them ought to “ esteem them der their understandings in vainly endea- very highly in love for their work's sake;" vouring to pursue the preacher through all and however pointed their assertions, or his mazes of reasoning, and all his flights of personal their strictures, or harsh their doceloquence, and in making guesses at his trines, or cutting their sentiments, may apmeaning; but the gospel will never be “a pear to some, they can point to a judgment joyful sound” to them, until they know its day, and say, “ your blood be on your import. Listen to the meek Redeemer own heads." If this spirit actuated every fulminating the terrors of judgment against minister of the gospel, there would be no hypocrites and Pharisees, and do not ima- base bending to sinful prejudice, nor gine him too severe or uncharitable ; No, despicable crouching to human pide, nor he was charity personified, but his charity servile courting of popular applause. was guided by divine truth, and influenced The horrors of a death-bed must be by a holy principle.

fearfully increased to an unfaithful minister; Ministers are not ordered to be success- his self-reflection must be most severe, and ful, but they are commanded to be faithful; the accusations of his conscience most harand the moment their fidelity ceases, that rowing; whilst he fancies that he sees the moment they should descend from the pul ghosts of many of his hearers rising from pit, and occupy a less important station. the pit of perdition, to upbraid him with his The plain truth will frequently offend the cruelty in deceiving their souls. And if carnal mind, but St. Paul expressly declares, we realize a judgment day, and single out “ If I please men, I am not the servant of the most wretched individual amongst the Jesus Christ.” If hearers are displeased at wretched myriads who throng the left hand the truth, be it so;—the minister makes his of the Judge at that day; it is not the man appeal to heaven, and refers the purity of who made a god and worshipped it, nor his motives, and the sincerity of his inten- he who spent his life in profanity, nor he tions, to Him who gave him his commis. who died heaping curses on his Maker; sion. The ears of many are so refined, that neither is it he who was misled by Mab

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