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shals” (2 vols. 12mo., New York, 1846), a work trated as far as the Coppermino river, which written for effect, and which has attained a he descended about 30 miles to the Arctic ocean, great degree of popularity. It was followed in thus determining the possibility of reaching the the same year by the "Sacred Mountains," and northern coast of America. He was promoted in the following year by “Washington and his for these services, and in 1787 returned finally Generals" (2 vols.). His melodramatic treatment to England. In 1795 appeared his “Journey of sacred subjects in the former work was much from the Prince of Wales's Fort, in Hudson's criticized. Among his later publications are Bay, to the Northern Ocean; undertaken by lives of Oliver Cromwell, Winfield Scott, An- order of the Hudson's Bay Company for the Disdrew Jackson, and Washington; “Adirondack, covery of Copper Mines, a North-West Passage, or Life in the Woods" (1849); the “Impe- &c., in the Years 1769, 1770, 1771, and 1772" rial Guard of Napoleon from Marengo to Wa- (4to., London). terloo" (1852), founded on a popular French HEARNE, THOMAS, an English antiquary history by E. M. de St. Hilaire; a “History of and author, born at White Waltham, Berkshire, the Second War between England and the Unit- in 1678, died June 10, 1735. He was gradued States” (2 vols., 1853); “Sacred Scenes and ated at Oxford in 1699, and became janitor of Characters;" and "Life of General Havelock" the Bodleian library in 1701, and in 1712 sec(1859). Mr. Headley resides near Newburg on ond librarian. Three years later he was apthe Hudson river. In 1854 he was elected a pointed architypographus of the university and representative in the legislature, and in 1855 esquire beadle of civil law; but being a strong was chosen secretary of state of New York for Jacobite, he was soon after compelled to resign the term of 2 years ending Dec. 31, 1857. his offices, from his refusal to take the oath of
HEALY, GEORGE PETER ALEXANDER, an allegiance to George I. Throughout his life he American painter, born in Boston in 1808. He continued to entertain' opinions hostile to the went to Paris about 1836, where he remained house of Hanover, and frequently introduced several years, alternating his residence there them irrelevantly into the prefaces to books with occasional visits to the United States. which he edited. His plodding industry, as well Among the pictures executed by him abroad are as his irritable temper, brought upon him the portraits of Louis Philippe, Marshal Soult, Gen. ridicule of many contemporary satirists, and Cass, &c. At home he has painted Calhoun, Pope has described him in the “ Dunciad," Webster, Pierce, and other prominent American under the name of “Wormius," as "in closet statesmen. He has occasionally produced large close ypent, .... on parchment scraps yfed." historical pictures, of which “ Webster's Reply Among Hearne's most valuable publications, to Hayne," illustrating a well known scene in which amount to over 40, and the greater part American legislative history, was completed in of which were printed by subscription at Ox1851, and now hangs in Faneuil hall in Boston. ford, are the “Life of Ælfred the Great," from At the great exhibition of Paris in 1855 he Sir John Spelman's manuscript in the Bodleian exhibited a series of 13 portraits and a large library (8vo., 1709); Leland's “Itinerary” (9 picture representing Franklin urging the claims vols. 8vo., 1710-'12); Leland's “Collectanea" of the American colonies before Louis XVI., (6 vols. 8vo., 1715), &c. for which he received a medal of the 2d class. HEART, á hollow muscular organ placed in Of late years Mr. Healy has resided in Chicago, the cavity of the chest between the lungs and and among his most recent works is a portrait above the diaphragm, which separates it from of President Buchanan.
the stomach. It is somewhat conical in shape, HEARD, a W. co. of Ga., bordering on Ala., the axis of the cone being directed obliquely and intersected by the Chattahoochee river; from its upper extremity downward and forward area, 286 sq. m.; pop, in 1852, 6,955, of whom to the left. The base of the cone is the upper 2,329 were slaves. The surface is hilly and well part of the heart; its apex is the lower. The wooded with oak, hickory, and pine. Gold, great mass of the heart is behind the sternum lead, and iron have been found, and the soil is in the middle of the chest, but the apex extends generally rich. The productions in 1850 were into the left side of this cavity. The upper 265,242 bushels of Indian corn, 35,034 of oats, border of the heart is just behind a line that 41,354 of sweet potatoes, and 3,384 bales of would unite the third costal cartilages; the cotton. There were 24 churches and 403 pu- apex of this organ corresponds to the interspace pils attending public schools. Value of real between the cartilages of the 5th and 6th ribs, estate in 1856, $888,033, Capital, Franklin, nearly 2 inches below the left nipple. In the
HEARING. See Acoustics, and EAR. adult, the heart is about 5 inches in length, 31
HEARNE, SAMUEL, an English explorer, in breadth, and 21 in the antero-posterior diamborn in London in 1745, died in 1792. In early eter. The weight of the heart varies accordlife he served as a midshipman under Hood, but ing to the weight of the body, and the proupon the conclusion of the 7 years' war he en- portion usually is nearly 1 to 170 in males and tered the employment of the Hudson's Bay 1 to 150 in females. According to most anatcompany, at whoso request he made several omists, it averages from 10 to 12 ounces in the journeys into the northern regions of British adult male, and from 8 to 10 in the fernale; but America in quest of a N. W. passage and of mines Bouillaud says the average weight in adults of the precious metals. In 1770–71 he peno. is only a little more than 8 ounces. In old
ago it is larger than in middle life.—The the base or at the apex of the heart. The right heart is essentially composed of 4 cavities or ventricle is somewhat pyramidal, and the other chambers; the two upper ones are the auricles, conical. The left ventricle is longer than the the lower ones are the ventricles. The au- right, and forms almost alone the apex of the ricles receive the blood brought by the veins heart. The right ventricle is often called anteto the heart, and the ventricles are the parts rior, on account of its being placed almost enfrom which the blood is sent to the various tirely in front of the other. In the two venorgans. The right auricle receives the blood tricles we have to study nearly similar parts, from the whole body except the lungs, and the which are the openings, the valves, and a peculeft auricle the blood from the lungs. (See CIR- liar apparatus chiefly destined to move some of CULATION.) In adults the two auricles have no the valves. Two openings exist in each vencommunication with one another, but both tricle, the auriculo-ventricular and the opening have a large aperture of communication with of the two principal arteries of the body. Tho the ventricles. Their walls are much thinner auriculo-ventricular opening is the aperture of than those of the ventricles; they are both in communication between the auricles and vencontinuity with the largest veins of the body. tricles; the larger opening belongs to the right The right auricle is the larger and thinner; ventricle. These two openings are nearly an it is an enlargement of the two venæ cavæ, inch in diameter; they are surrounded by a united with the right ventricle and separated ring of fibrous tissue, to which are attached the from the left auricle by a muscular wall. Many valves which will be described below. In the openings may be seen on the internal surface right or anterior ventricle we find the opening of this auricle: 1, on the posterior and inferior of the pulmonary artery, which is in front of part, the very large opening of the inferior vena the auriculo-ventricular aperture, near the wall cava; 2, on the upper and front part, the superior which separates the two ventricles (the septum vena cava; 3, on the posterior and lower part, the ventriculorum). In the left ventricle is the coronary sinus by which the blood returns from opening of the aorta, in front and to the right the substance of the heart; 4, between the of the auriculo-ventricular aperture. The semiright auricle and the corresponding ventricle, lunar valves surround the orifices of the aorta the auriculo-ventricular opening; 5, many mi- and of the pulmonary artery, in each of which nute apertures through which a number of they consist of 3 semicircular folds of the endosmall veins throw blood into the auricles. In cardium, the lining membrane of the cavities the right auricle of the adult we find several of the heart, with an addition of fibrous tissue. parts which are vestiges of the fetal heart; for Between each valve and the corresponding part instance, the Eustachian valve, which is much of the aorta or pulmonary artery there is a pouch diminished; the fossa ovalis, usually a simple due to a partial dilatation of these vessels. The depression on the interauricular walls, where valves have an upper border (the free one), an opening exists in the fætal heart, which may which is straight, and a lower or adherent one, remain in adults and allow a mixture of the which is convex. The other system of valves black and the red blood. Both the right and found in the heart differs in its two ventricles; left auricles have an appendix, the shape of in the right one the system is composed of 3 which has some resemblance to a dog's ear, triangular segments, and in the left of only 2; The muscular walls of the appendices are very the first forms the tricuspid valve, the second thin, and their cavity is a continuation of that the mitral valve. Both are composed of double of the auricles. In the two appendices there folds of the lining membrane, with an addition are small muscular columns, some of which are of fibrous tissue, and probably of some muscucylindrical, running transversely across the inner lar fibres. They adhere to the margin of the surface of thoso extremities and of the adjoin- auriculo-ventricular opening, and give insertion ing parts of the auricles. These columns, called by their lower surface and their free margin to musculi pectinati, on account of their resem- a number of tendinous cords, the chorda tendiblance to the teeth of a comb, are more numer- new. The disposition of the various parts of ous and larger in the right than in the left ap- the valvular apparatus in the ventricles is such pendix. The left auricle presents 5 openings; that when these two muscular pouches contract one is the aperture communicating with the (which action is called systole), the blood tendcorresponding ventricle, while the 4 others be- ing to pass by the 4 openings pushes open the long to the pulmonary veins. These last open- semilunar valves and escapes freely by the two ings are placed very near one another, and arterial trunks; while, on the contrary, the trisoinetimes, instead of the two by which the red cuspid and mitral valves are pushed upward blood comes from the left lung into the auricle, and prevent the reflux of this liquid into the there is but one large aperture on account of auricles. The reverse takes place at the time the merging of the two left pulmonary veins. of dilatation or diastole of the ventricles; the The two ventricles constitute a much larger blood tends to return into the dilating ventricles, portion of the heart than the auricles. The and pushes down the semilunar valves, which walls of the left ventricle are notably thicker at once completely prevent its falling into the than those of the right; and while the latter ventricles; while, on the contrary, the mitral ventricle is thicker near its base than elsewhere, and tricuspid valves relax. In the two venthe left one is thicker in its middle part than at tricles a large number of muscular columns (columnæ carnem) are found. These columns and from left to right on the anterior surface. are rounded, and originate from almost all the The bundles of fibres belonging properly to parts of the inner surface of the ventricles, upon but one of the ventricles are chiefly transverwhich they interlace in all directions. There are sal and circular, so that their general direction 3 kinds of muscular coluinns: 1, those which is perpendicular to that of the fibres common are adherent all along their length with the to both ventricles. The bundles of fibres comwall of the ventricles; 2, those which are free mon to the two auricles are transversely placed in their middle and adherent by their two ex- on the anterior and lateral surfaces of the auritremities; 3, those which adhere by one ex- cles. The bundles belonging properly to but tremity to the ventricular wall, and by the other one auricle are circular or spiral, and they cross are attached to tendinous cords inserted upon one another in several directions. Around the auriculo-ventricular valves. The heart is nearly all the venous or other openings of the covered outside by two membranes, constituting heart there are bundles of circular fibres, formthe pericardium, and lined inside of its cavities ing a kind of sphincter.-Two arteries, the anby a thin membrane, the endocardium. The terior and the posterior coronary, furnish red pericardium consists of a strong layer of fibrous or arterial blood to the tissue of the heart; tissue attached to the fibrous part of the dia- they originate in the aorta near its origin. The phragm and to the areolar tissue investing the veins are more numerous, as, beside the great large blood vessels springing from the heart. cardiac vein, there are many smaller ones. The It is a membranous bag fixing the position of nerves of the heart come from two sources, the the heart. The inner surface of this fibrous par vagum and the sympathetic. A peculiar anbag is lined by a very thin membrane, which atomical feature of the heart is that it contains is the serous pericardium, extending also over many small nervous ganglia, most of which the outer surface of the heart, which it covers can be seen only with the aid of a microscope. entirely. The endocardium is an extremely - Like all the other muscles of living animals, thin membrane which lines all the cavities of the heart is endowed with irritability, i. e., the the heart, and is a continuation of the inner or power of contracting after excitation or stimepithelial membrane of the blood vessels. Itulation. The heart is among the organs in is composed of a superficial layer of epithelium, which irritability lasts longest after death. It placed upon a delicate stratum of fine fibres of is not true, however, that, as stated by many fibrous tissue. The various valves of the heart physiologists, the heart is always the last organ are chiefly formed by folds of this membrane.- to lose its vital properties. Fontana showed The muscular tissue of the heart presents sev- that the muscles of animal life (those of the eral interesting characters. In man and the limbs and trunk) often remain irritable longer higher vertebrates it belongs essentially to the than the heart; Dr. Brown-Séquard has shown variety of striated or striped muscular fibres, that the iris, the diaphragm, and also the musbut the stripes are less marked and the fibres cles of the limbs, very often remain much longer thinner than in the muscles of animal life, and irritable than the heart, not only in animals but the fibres present the important peculiarity of also in man. The cases of longest duration of branching and anastomosing one with another, irritability after death, in man, recorded by so that the whole muscular fabric of the ven- Nysten, are, for the heart, 16 hours, and for tricles and that of the auricles may be consid- the muscles of the limbs, 27 hours. Carpenter, ered as two complicated and inextricable net- with almost all physiologists, says that the irriworks of muscular fibres. Another peculiarity tability of the heart is much less speedily deof the heart is, that there is no areolar tissue, stroyed in cold than in warm-blooded animals, or but little, between the fibres, while in other This is not always true. Remak has seen irritamuscles there is a considerable quantity of this bility continue two days in the heart of birds tissue between fascicles of fibres. In conse- and mammals; Brown-Séquard, from 31 to 34 quence of the interlacement of the fibres of hours in Guinea pigs and rabbits, and 53 hours the heart, it is very difficult to ascertain their in dogs; and M. Vulpian, 53, 57, and even more disposition; but if, instead of trying to follow than 931 hours in dogs. So far as we know, up small fascicles of fibres, we study the arrange this exceeds the greatest duration of the irriment of large bundles or bands, we find that tability of the heart in cold-blooded animals. there are two distinct divisions of the fibres Most physiologists, also, say that in newly born of the heart: 1, those belonging to the two animals the irritability of the heart lasts longer ventricles or the two auricles; 2, those which after death than in adults. This is true only belong only to one of these pouches. The in certain circumstances, and especially when bundles common to the two ventricles seem to the temperature of the newly born animal has emerge from the apex and to cover the anterior been much diminished before death. Very and posterior surfaces of the heart. At the frequently the heart remains much longer irribase of the ventricles many of them are in- table in adults than in newly born creatures.serted upon the fibrous zone placed between As long as life lasts the heart has movements these pouches and the auricles. At the apex which afford a most interesting study. We of the heart these bundles partly pass inside of will first examine the circumstances relating to the walls of the heart, and partly pass obliquely the persistence of these movements after death. from right to left on the posterior surface, In normal conditions the two auricles contract
together, and push the blood into the ventri- greatest importance ; we mean that by which cles, which, after having been distended by this the heart's action is completely or incompletely liquid, contract in their turn and force the blood stopped at once, and through a peculiar agency into the pulmonary artery and the aorta. On of the par vagum, one of the nerves of the account of their perfect regularity these move- heart. This stoppage of the rhythmic movements are called rhythmical. Whatever be the ments of the heart is the usual cause of death cause of rhythmical action of the heart, it seems when it occurs suddenly after an emotion, after to be in this organ itself, as when the heart is a wound (without much hæmorrhage) of tho taken out of the chest it continues to move abdomen, after a blow on the cardiac region, rhythmically. Even parts of the heart sepa after certain injuries to the medulla oblongata rated from the rest, as shown first by Haller, or the medulla spinalis, after drinking cold water oontinue, though but for a short time, to have on a warm day, after a shower bath, &c. It is rhythmical movements. The movements of in this way also that, in a few cases, chloroform the heart may persist for a long while after has caused death. Dr. Brown-Séquard has asdeath. Boyle has seen them continue 7 hours, certained that when the heart is stopped by and Hooke more than 12 hours, in newly born this peculiar influence of the nervous system, dogs; M. Vulpian has seen the auricles of a it is usually easy to set it in action again by dog moving regularly 263 hours after death, mechanical excitation made by pressing upon it and M. Rousseau states that, in a woman decap- through the walls of the chest. He has found itated at Rouen in 1808, the 4 parts of the that every effort of dilatation of the chest, in heart had regular contractions and relaxations inspiration, is associated with some retardation 29 hours after death. We feel inclined to of the heart's action. Taking notice of this doubt the correctness of this statement, as wo fact, on the one side, and, on the other, of the find that the rhythmical movements of the ven- most important fact that when respiration is tricles, if not of the auricles, had ceased entire- not free the movements of the heart increase ly in less than one or two hours in 23 decapi- in frequency and energy, it seems quite rational tated men, observed by Nysten, Rochard, to recommend, as was done empirically by an Brown-Séquard, Harless, Kölliker, &c. In 4 author of the last century, to stop respiration criminals, hanged in Boston and Philadelphia, for a short time (half a minute or a little more) the movements of the heart had stopped in in cases of syncope. The nervous centres may much less than an hour. When the movements act also upon the heart to produce an augmenof the heart have ceased, it is usually possible tation or a disturbance in the movements of this for a time to reproduce them. Any kind of organ; but whether these modes of influence excitation, such as a puncture, a pressure, the are direct or not is not yet positively decided. influence of water, of acids, of alkalies, of heat, It is certain, however, that at least in many of galvanism, &c., may renew for a few minutes cases it is through a disturbance of the respiraor a much longer time the regular contractions tory function that an increase or irregularities and relaxations of the heart. We have already in the movements of the heart are produced. said that the heart may have its rhythmical Most of the German physiologists now admit action, although separated from the body, that the cause of the rhythmical movements of and therefore deprived of the action of the the heart is a peculiar influence exerted by small cerebro-spinal axis. We may add that the re- nervous ganglions that are found in this organ. searches of Bidder on the spinal marrow, and But it seems very improbable that the rhythm those of Brown-Séquard on the medulla oblon- of the heart's action depends upon those small gata and the rest of the encephalon, show that ganglions. In the first place, the heart in the the extirpation of these nervous centres, in embryo, before the formation of the nervous certain animals, does not necessarily cause system in its tissues, when even the muscular death, and, still more, frequently allows life and fibres are not yet formed, is composed of cells, therefore the movements of the heart to con- which have regular movements; in the second tinue for many months, without any apparent place, the various veins in the neighborhood of alteration. Moreover, it is well known that the heart, although there is no ganglion in them, the heart has regular movements during the have rhythmical contractions, as was well shown intra-uterine life in monsters deprived of any by Allison of Philadelphia; in the third place, part of the cerebro-spinal centres. It seems, all the contractile tissues of the body, although therefore, that we ought to reject entirely the without ganglions, may, as shown by Brown-Séviews of Legallois and others, who considered quard, have rhythmical movements.-Muscular the spinal cord or the medulla oblongata as the irritability in the heart, as everywhere else, seems source of excitation of the movements of the to depend upon a peculiar influence of blood. heart. But if those parts of the cerebro-spinal The movements of the heart, therefore, as they axis have not the function which was attribut are simple manifestations of the irritability of ed to them, they have undoubtedly a very great the muscular tissue of that organ, depend also influence upon the heart, either to stop or di- upon the action of the blood. Experiments minish, or to increase or disturb, its rhyth- made by Erichsen show that ligatures upon the mical action. There is a peculiar influence of arteries of the heart are soon followed by the the nervous system upon the heart which is cessation of its movements. More decisive still insufficiently known, although it is of the facts published by Brown-Séquard show that when not only the movements but also the irri- the heart is felt to strike in its normal position, tability of the heart have ceased, an injection are our surest guides. Such cases are usually of blood into the coronary arteries may restore connected with undue excitability of the nerboth the irritability and the movements of this vous system, with derangement of the stomach, organ. We cannot enter here into the exposi- or with the abuse of tobacco. The serous sac tion of the principal views of the cause of the enveloping the heart may be inflamed, constirhythmical movements of the heart, but it tuting pericarditis. The symptoms of this disseems most probable that this cause consists in ease are frequently trifling; the most common a peculiar change taking place in the muscular is pain referred to the cardiac region or to the fibres of the heart, and that this change is due epigastrium, and extending sometimes toward to the influence of certain principles existing the left shoulder. The pulse, often quite unafaround these fibres.-Much discussion has taken fected, may be frequent and irregular; dyspnea place concerning the direction of the movements is not commonly marked, thongh in rare cases of the heart. Harvey and two able American it may become so severe that the patient is experimenters, Drs. Pennock and Moore, assert unable to assume the recumbent posture (orthat when the ventricles contract they elongate thopnea). In the course of the disease lymph and their apex protrudes. Most other physiolo- is effused, by which the opposite surfaces are gists affirm, on the contrary, that the ventricles roughened; afterward serum may be poured shorten. These two statements may be recon- out, distending the sac of the pericardium. ciled; the writer has seen the ventricles short- When recovery takes place, the two surfaces of en in dogs as long as the movements of the the pericardium are found adherent, thus to a heart were vigorous, and elongate when they greater or less extent obliterating its cavity. became feeble. Carpenter states that the apex Rheumatism and Bright's disease are the most of the ventricles when they contract describes common causes of pericarditis. Sometimes it a spiral curve from right to left and from behind arises from an extension of inflammation from forward. The truth is that it is from left to the neighboring pleura, and it may result from right that the point is directed. Harvey thought external injury. For the diagnosis of pericarthat the heart, at the time of the ventricular ditis we must rely mainly on the physical signs. contraction, strikes the wall of the chest by its Early in the disease there is developed over the apex. This view is no longer admitted ; almost heart a friction sound commonly double, superall physiologists think that it is by the middle ficial, limited in extent, and not heard along or the upper part of the right ventricle that the the course of the great blood vessels. Where heart strikes the breast. Strange to say, it is the disease proceeds on to effusion, as this instill a debated question whether the beating creases, the friction sound may be gradually lost, takes place during the systole or contraction of at the same time that the area of the heart's the ventricles, or during their dilatation or dia- dulness as discovered by percussion is markedly stole.-Two sounds accompany the movements increased. Pericarditis is not an uncommon of the heart; one of these sounds, known as disease, and in itself is commonly attended with the first, is dull and prolonged, while the second little danger; when however the inflammation is sharp and short. The first sound coexists affects the muscular substance of the heart, the with the beating of the heart and the pulsation affection becomes one of the gravest characof arteries; the second is produced a very short ter. It commonly requires little treatment; the time after the first. The principal cause of local abstraction of blood from the cardiac rethese sounds is the sudden tension of the valves gion, and the enforcement of rest with proper of the heart. The first sound is principally due regimen, are all that will be found necessary; to the sudden tension of the auriculo-ventricu- when effusion has taken place, diuretics may be lar valves when the ventricles contract; the resorted to; the employment of mercurials is second sound is chiefly due to the tension of the advocated by many practitioners. Occasionvalves at the origin of the aorta and of the pul- ally pericarditis is of tubercular origin. Tumonary artery. Other causes add their action bercles deposited beneath the pericardium give to the preceding for the production of these two rise to inflammation, and the plastic matter sounds, or of one of them; we will only men. exuded becomes a nidus for a new formation the impulse of the heart against the wall tion of tubercle. Such pericarditis is essenof the chest, the muscular contraction, the col- tially chronic, and like tubercular peritonitis it lision of the particles of the blood with each may exist where there is no corresponding deother, and the friction of this liquid against velopment of tubercle in the lung. "The disease the walls of the heart and against the mouth of may be suspected when in a tuberculous conthe aorta and of the pulmonary artery. (See stitution pericarditis arises without the coexBLOOD, CIRCULATION, PULSE, &c.)- DISEASES istence of Bright's disease or rheumatism, or OF THE HEART. · The heart may be affected pleuropneumonia, or without the reception of with violent palpitation or with irregulari. an external injury. In its treatment the paty of action without the presence of organic tient's strength should be early supported, and disease, and it is not always easy to discrim- while.counter-irritation may be employed, cod inate such cases; the absence of increased dul- liver oil, iodine, and the preparations of iron ness over the cardiac region, of all signs of val- may be administered with some prospect of yular affection, and the fact that the point of benefit.-Endocarditis. The lining membrane