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yet fitted for the system; it now pagg. On the structure of the frame itself es through the pyloric orifice of the their operations are continually carristomach into the duodenum, (a portion ed on ; for it must not be forgotten, of intestine,) and becomes there mixed that the organized living machine is with the pancreatic juice and bile, undergoing a double set of internal The pancreatic juice is a fluid prepar- operations, its destruction and renovaed by a gland termed the pancreas, the tion; and whatever comes off in the bile by the liver. By the action of constant wear of this machine is taken these fluids on the pulpy mass, a com- up by these vessels, the absorbents, or, plete conversion is effected, and that as they are called, lymphatics, from portion fitted for the purposes of the the limpid fluid we always observe animal economy is, as we have said, them to convey. termed chyle. If we examine the The minute tubes which form the state of these minute tubes or vessels commencement of the lymphatics, are in an animal recently killed, and be- furnished with orifices so small as to fore the vital warmth is extinguished, be totally imperceptible to the naked we shall see them (at least if the ani- eye; and each orifice, endowed with mal has been lately fed) filled with a the power of contracting or dilating, milky fluid, from whence they have absorbs or refuses, according to the their name lacteals : this milky fluid peculiar impression produced by the is the chyle.
object in contact. The lacteals having thus absorbed In what manner the lymphatics, and this nutritive portion of the food, after indeed the whole absorbent system, communicating freely with each other, propel or convey the fluids they conpass through certain glands termed tain, is a question on which physiolomesenteric, where the chyle appears to gists have entertained very different acquire new properties. Emerging views ; some, for instance, and these from these glands, the lacteals carry eminent men, have asserted it as a the chyle onwards, till they enter, at fact, that fluids circulate through and last, into the thoracic duct, a vessel ascend these minute tubes, contrary which passes along the spine, and to the law of gravitation, not from pours the chyle into a large vein, al- any propelling power in the tubes most immediately entering the heart, themselves, but by that principle termed the left subclavian vein ; here which causes the ascent of liquids it becomes mingled with the blood. through tubes of great minuteness, It has not yet, however, lost its cha- termed capillary attraction. To this racter ; but after passing through the opinion, however ingenious and appaheart, and thence through the lungs, rently satisfactory, there are many it becomes incorporated with the rest strong objections : for were it correct, of the blood, from which it is no we might expect that neither age, nor longer to be distinguished.
sex, nor temperament, nor habit, There is, however, another set of would produce the least variation or vessels, which, as well as the lacteals, irregularity in the absorbing power, terminate in the thoracic duct, and and that all would proceed with unicontribute likewise to the repair and formity. But this is far from being preservation of the system.
the case ; for as much so as every viThroughout every part of the tal function, the action of the absorbframe, in the interior as well as on ents is liable to irregularities inconthe surface, are distributed innumera- sistent with the theory just mentioned. ble vessels, destined to absorb and Indeed it is much to be doubted whecarry into the blood the superfluous ther any of the functions of organized fluids of the body, as well as all sub- bodies, on which their vital existence stances immediately within the sphere depends, are to be accounted for upon of their action. External bodies are purely mechanical principles ; a supnot the only ones on which they act. position which has led to theories very ingenious, but unfortunately errone- Hâller, who often gives the name of ous.
lymph indiscriminately to the fluid of It appears more possible, according the absorbents, and to the serum of to our ideas, that the absorbent ves- the blood. sels are endowed with a sufficient From the circumstances attending power of carrying on or propelling the the production of the lymph, we might fluids they contain, by some peculiar be led to judge, that its nature and action in themselves, which they are component parts would be subject to enabled to exert so as to answer the variety and change ; and this is found end in view.
to be the case; but in the chyle these The lymphatics, after arising from differences are still more evident, various parts of the frame, the surface arising from the various substances as well as the interior, by minute used as food. Indigo, madder and tubes in close contact, unite and di- beet-root tinge it with their respective vide, and so intermingle with each hues. It is, however, as we have other as to form a close network, said, in general white, slightly viscid, wbich, with a similar tissue of nerves and much resembles milk. When reand blood-vessels, forms the cellular moved from its vessels and exposed to and membranous textures of the body. the air, it separates into two parts, Emerging thence, and proceeding viz. : fibrine and serum and the onwards, they form distinguishable lymph also, under similar circumtrunks, and again enlarge by the union stances, undergoes the same change. of others; and multitudes of these Both the lacteals and lymphatics run together a parallel course, forming terminate in the thoracic duct, which companies proceeding from different empties its contents into the left subquarters, and by different routes, for clavian vein. At the point of junction the same destined place; the whole, between these a valve is placed, so however, communicating largely with constructed as effectually to prevent each other.
the blood from finding its way into the In various parts, and for reasons not thoracic duct, but which offers no imfully known, companies of these absorbe pediment to the exit of the chyle. ents form themselves into masses of From this source then the blood reconvolutions, differing in number and ceives its supplies, and nothing can magnitude, and intermingled with a incorporate with the system, or be resimilar congeries of blood-vessels. ceived into it, without proceeding These masses are the glands, (ob- through this channel. served in the neck and other parts,) Having now conducted the nutrithe uses of which are not, as yet, fully ment through its various stages, till it ascertained, although it is most proba- enters into the blood to supply the ble that some change is effected by continual drain upon this reservoir of their agency on the lymph, by which vitality, we shall follow up the subject, it is rendered more fit for the purposes and proceed to give a more detailed of the animal frame ; and this would account of that most beautiful and infurther appear, from the increased teresting phenomenon of the animal tendency to coagulate, which it mani - frame, the circulation of the blood. fests after passing through the glands, The circulation of the blood is an (which it does slowly, as if impeded operation immediately connected with by the way,) as well as some altera- our existence, and on which it detion in its appearance.
pends; and will it not excite our asAt the same time, however, it must tonishment, that two centuries have be observed, that the real nature of scarcely elapsed since its laws have the lymph is far from being well un- been at all correctly ascertained ! and derstood. By some it is considered even now, many points are disputed, as' analogous to the serum of the and enveloped in obscurity. We may blood, which is indeed the opinion of with safety conclude, that the ancients were in almost total ignorance re- point of union between them a thickspecting the real nature of the circula- ening is to be seen, called the turbertion, or the mode in which it is per- culum Loweri. Within the auricles formed : for although, perhaps, among bundles of muscular fibres project their writings, passages may be found from the sides. These, from their apparently indicating some acquaint- resemblance to the teeth of a comb, ance with the subject; yet as they are termed musculi pectinati. The have left us no distinct account, and partition between the right and left as their works abound with gross ab- auricle is called the septum aurisurdities respecting it, our conclusions cularum. are certainly warrantable ; especially T he right auricle communicates when we consider, at the same time, with the right ventricle by means of how little anatomy was cultivated as a an opening, denominated the ostium science among them.
venosum; at the edges of which, The discovery of the true nature of within the ventricle, are three valves, the circulation is due to Harvey, who or rather a valve divided into three flourished in the 17th century; but parts, called the tricuspid valve, from since his time, succeeding physiolo- its resemblance to the points of three gists have diligently applied their ta- spears; to the edges of this valve lents to the subject, (a wide field for small muscular bundles are attached, investigation,) and have added by called carne columna, by means of their labors many new facts to the tendinous chords, (chordæ tendina.) discovery of their immortal predeces. From the right ventricle the pulmonary sor.
artery arises, at the root of which, inVarious and important are the uses ternally, are situated the three semiwhich the circulation of the blood is lunar valves, with a small white body destined to serve :--by its means the at the edge of each, termed corpus various secretions are performed, the sesamoideum. Into the left auricle the growth of the body promoted, and its four pulmonary veins enter. The decay and losses repaired ; and be- coats of this auricle are thicker than sides all this, it is, in some mysterious those of the right, otherwise it exhimanner, connected with that inexpli- bits much the same appearances. It cable subject, the animal temperature. opens into the left ventricle, having
We shall in the first place, then, also at the opening a valve, but dividendeavor to give a general sketch of ed only into two parts, called from its the anatomy of the heart, the great likeness to a mitre, valvula mitralis. agent of the circulation; and then The great difference which the left explain the nature and constituent ventricle exhibits is the superior parts of the blood-the fluid of vi- strength and fleshiness of its walls, tality.
indicating the vigorous action it is The heart is a large hollow muscle, destined to maintain ; emerging froin situated in the chest, between the lungs, it is seen the aorta, or main artery, and enfolded in a bag called the peri- with three semilunar valves internally cardium, the inner lining membrane of at its root. The use of the various which is reflected over the surface of the valves we shall explain when consiheart itself. The heart is divided in- dering the course of the circulation. ternally (we are speaking of man) into Having thus briefly described the four cavities : the right and the left auri- general anatomy of the heart, we cle, and the right and the left ventricle. shall next proceed to examine the Into the right auricle, two veins, call- properties and constituent parts of the ed the venæ cavæ, enter ; one bring- blood itself. The blood, when drawn ing the blood from the upper, the from the body, and suffered to remain other from the lower parts of the in any vessel, quickly separates into body. The two veins unite at their two parts,-one a thick yellow fluid, entrance into the auricle, and at the called serum, the other a tenacious solid mass of a dark red color, termed of nutriment, more florid if exposed crassamentum. The relative propor- to oxygen, and darker if exposed to tions of these vary exceedingly, ac- carbonic acid or hydrogen. The cocording to age, sex, temperament, loring matter has been said to contain mode of life, &c.; yet generally speak- oxide of iron; this, however, later ing, the estimate may be made as ten chemists have disputed, and Dr. of the serum to fourteen of the cras- Wells, in his “ Observations and Essamentum. The serum contains wa- periments on the Color of Blood,” af. ter, albumine, muriate of soda, and ter much investigation, decides against potass, phosphate of soda, animal mat- the theory; indeed, his arguments, ter, &c.
which are too extended to be here inThe crassamentum is divisible into troduced, seem to settle the point at two parts, fibrine, and the coloring once, confirmed as they hare been particles of the blood. The compo- by subsequent inquirers—Berzelius, nent parts of fibrine are carbon, oxy- Brande, and Vauquelin. Mr. Brande gen, hydrogen, and azote. When the has even succeeded in dying cloth coloring matter of blood recently with it, but he found considerable drawn is examined with a microscope, difficulty in fixing the color ; the most it is found to consist of globules of effectual mordants he discovered were, extremne minuteness, of a red color, the nitrate and oximuriate of mercury. but varying from different causes, be- —The specific grarity of the blood is ing paler from illness and deficiency estimated at 1050, water being 1000.
EXTRACT OF A LETTER FROM PARIS.
CHATEAU DE LAGRANGE–LAFAYETTE. In the country, as I told you in my some thirty years back by Mr. Fox, last, all the better society of Paris is give a sort of feudal air to the castle, now buried, and Lagrange, from which which mingles curiously, but not disaI am just returned, since the end of greeably, with the republican associthe session, has been the Chaussée ations attached to the name of its d'Antin, where all the most illustrious owner. The chateau is surrounded by men in the Chambers, or in literature, a fine park, which is stocked in a manhave by turns rusticated. There is no ner that would not harmonise with want of strangers either; and, as you your English notions. Instead of would expect, the Americans especial- slight, graceful, aristocratical deer, ly are to be seen there in multitudes. nothing but the tiers état of the animal The last very conspicuous English creation, blebeian cows, and more visitor there, was Sir Francis Burdett, plebeian sheep, are to be seen grazing who has been exerting his eloquence within its precincts. For these last in favor of the droit d'ainesse ; from animals, the General has a great afwhich, exclaimed his distinguished fection. He superintends their eduhost, “Thank God! the revolution cation in person, and exhibits a most has delivered us!”
philomelical zeal in improving the The chateau is delightfully situated. breed. The English friend who was It is about thirteen leagues from Pa- with me had never seen Lafayette. ris, and the road is through the rich He was wonderfully struck with his plains of the ancient province of Brie. venerable appearance, and especially We quitted the diligence at the village with the calm, full, and scarcely of Rosoy, about half an hour's ride wrinkled countenance, upon which a from the chateau, where a carriage, record of the words he has spoken, sent by the General, was waiting for and the deeds he has performed, for us. Ruined Gothic towers, covered his country, seemed to be legibly enwith ivy, which was planted there graven. His head, over which seventy-two years have passed, is lofty,-a precautions which it was possible for peruque à la Titus covers it, and does him to adopt. He renewed bis denot take much from its patriarchal ap- clarations of inviolable attachment to pearance. His tall figure adds to the the King, and did everything to conimpression of nobility which his coun- vince him of their sincerity ; but the tenance produces upon your mind; distrust of the Court continued, and it and, in short, there is nothing about is to this cause alone, that we must him, even to his slow and painful attribute the events which followed, walk, a reminiscence of his long cap- and which were arrested by that very tivity at Olmutz, which does not at plebeian militia, by that very Lafayonce attract and affect the heart. ette whose offers of assistance had
The severest charge ever brought been suspected or disdained. Meanagainst this great man, whose name is time, a band of wretches killed some so dear already to two of the greatest of the body-guards whom their comnations of the world, and will, some rades could not or would not defend. day or other, be pronounced with re- The apartment of the Queen was forcverence in its remotest corners, relates ed : they rushed to her bed ; she esto his conduct respecting Louis XVI. caped, half-naked, just in time to save and the Royal Family on the memo- herself from the poinards of the asrable 6th of October. In a work, con- sailants—the Parisians rushed to their sisting of various interesting anec- assistance-entered the house in defidotes, from the pen of M. Touchard ance of the opposition of the persons La Fosse, entitled “ La Revolution, they came to rescue, and the King and l'Empire, et La Restoration," which Queen were saved. I should like to appeared in the course of last week, know where was the negligence of the there is a page upon the insurrection national guard ? Where any want of of Versailles, which sets this matter foresight in their chief?” in so clear a light, and so completely The volume from which I have borexonerates Lafayette from blame, rowed this passage contains many that I am sure you will thank me for other pages, doing equal honor to the transcribing it.
conduct of Lafayette, under the Re" For a long time,” says M. Tou- public and the restored Bourbons. chard, « it has been fashionable to lay Indeed, of the two hundred and twenthe responsibility of the events of the ly persons, whose portraits are hung 6th of October upon the veteran of the up in the gallery of M. Touchard, it American and French Revolutions. would not be rash to affirm that LaEven those who were unwilling to ac- fayette is the only one who has recuse him of direct bad faith, have in- mained the same, amidst all the timated that he was at least sadly de- changes which, during the third of a ficient in foresight; and he has been century, have been passing under our nicknamed, Le dormeur de Versailles. eyes. Let us see whether he merits their If Lafayette complies with the reproaches. M. de Lafayette came wishes of his friends, and writes a to Versailles on the 5th, at ten o'clock history of his life, how many new in the evening. He instantly placed facts he will reveal; how many inguards without the gate ; but the com- trigues he will be able to explain ! for, manders of the body guard positively to say the truth, he is the only Frenchrefused to admit the soldats bourgeois man who lived through the Revolution into the interior. The royal family without participating in its excesses ; itself rejected the offers of the Com- beheld the empire, and was not dazzled mander-in-chief of the National by its splendor; took part in the esGuard,--a guard which a very cele- tablishment of the monarchy, and nebrated person stigmatised as the ca- ver defiled himself by any of its intenaille nationale. In spite of this rested conversions. These three petreatment, Lafayette neglected no riods of modern French history, re