Anucher affection which sometimes flows injuries (and especial? punctured wounds of the external comets of the SL s ndamnatie mé cosequens extensite suppuration in the joose tissue condecting the tendra of the muscle mering the top of the bead with the perioration. When this afectirs is suspected to be coming a leeches should be put on the head in large numbers about the wound, cous clivery appled; our ff matter shold form, one or more free casions should be made through the scalp to let in on and the part afterwards treated like a common abscess. In cases in which the bone has been exposed, the same prom, ml kcal treatment should be employed When the bone itself is injured, ne active trestment should ever be särpted, unless there are evident signs that the brain is sufering from compression or hocher remeclable HEAD BOROUGH the former name of the ordetalle or bead of a borong The term is also meed in Scotland to denote the borough in with the HEAD, INJURIES OF THE From the many pernier and important features with they preseat in juries of the bead have property received a separate endeidematice in all prstems of surgery; for not only is the brain so essential to life that even its least injury must be regarded as serios, but the parts around and guarding it have many pennar Des. The injuries of the head are best ccost, bered as they affect the parts inclosing the brain or the brain itself In mere bruises of the soup two circumstances are worthy of notice. A vessel of some size may be burst without the skin over it being wounded in which case & most oplos eftem of Blood takes place, raising up the scalp from the seal and procacing rapid swelling of the whole of the upper part of the bead. It needs, however, no particular treatment; no incision should be made into it, for if cold wet cloths be diligently applied, the blood will be again rapidly absorbed A common superficial wound of the scalp needs Do particular treatment It should be closed with Saving-plaster after the hair around it Las been The vessels of the firs mater may be restored by the jer from a tire which does not even break tile sk The blood that fows from them seemmalating between the dura mater and the skal produces compression of the train. The only bope in these cases is to bleed the patient largely, to check the dow of blood in the bead, and if that be not evidently beneficial to apply the trephine wherever it is not pricate that the blood may be found and removed Instead of blood parlent matter may collect between the dura mater and skal and produce equally fatal rests This is dated by the patient SOLT some considerable time after the accident) complaining of beadache, restlessness, and extreme languor; be has frequens irregular shiverings, his prise is quick and hard, and be cannot sleep; if ordered by treatment all these symptoms increase, and are shortly fourwed by delirium, conraisions, insensibility, or paralysis which are no distant precursors of death. A mer frems on the part struck and if this be opened, the pericranium will be found detached to some extent from the skull. The brain itself may suffer injury either from blood effused in it by rupture of its vessels, from compres sion by fractured portions of bone being forced down it has not appeared that bleeding, which is the remedy popularly expected for all such accidents, has at all diminished its primary symptoms, nor has the contrary treatment by stimulants been more successful. The patient, while suffering from the immediate stunning consequences of the blow, should merely be kept quite warm in bed, and carefully watched; if the pulse grow weaker, the extremities colder, and the other symptoms of sinking seem increasing, upon it, from wounds, from concussion, or from inflammation and its various effects following any of these injuries. The first does not differ in its symptoms from the cases of common apoplexy with effusion of blood [APOPLEXY], and admits of no mechanical treatment. The second class comprehends the most important injuries of the head: those of 'fracture with depression,' as they are called, and those which occasionally happen in children, in which the skull is indented without being broken. The stimulants are first called for, and should be given symptoms of such an injury are insensibility, generally in direct proportion to the degree of pressure; the breathing is slow, laboured, and snoring, and at every expiration the cheeks are puffed out and elevated; the pulse is slow and irregular; the pupil widely dilated and insensible to light; the patient neither feels nor moves, and lies as if in a fatal state of apoplexy. The evident and indeed the only mode of affording relief is to remove the pressure from the brain, by exposing the fractured part of the skull by enlarging the wound in the scalp, or making a fresh one, and taking away or elevating all the portions of bone that are depressed. Such cases, and all others in which compression cannot be mechanically relieved, can only be treated like common apoplexy, by bleeding the patient, by cold sedulously applied, and by rigorous reducing measures. The immediate consequences of wounds of the brain vary greatly, and indeed unaccountably: in some cases a very slight injury is rapidly fatal, as in those (of which many are now recorded) in which a pointed instrument has passed in through the orbit, and produced almost instant death; whilst in others, severe and extensive injuries, as from gun-shots, have been followed by serious symptoms at only a late period from their reception. The last injury of the brain that needs particular notice is that called concussion or commotion. In its slightest degree it is merely a stunning, from which perfect recovery takes place in a few minutes; when most severe, it is rapidly fatal; but, even then, a post-mortem examination discovers no alteration whatever in the structure of the brain. One of the most interesting points in surgery is the diagnosis of concussion from compression of the brain. As the latter seldom occurs without the former (for of course a blow which would fracture or indent the skull would violently shake the brain), compression has the symptoms of concussion, with the addition of some of the most severe which we have already mentioned. In concussion the patient is insensible only to slight impressions, for if he be loudly called to, he will wake up, answer a word or two, perhaps even rationally, and then relapse into the same state. If he be severely pinched or otherwise irritated, he will withdraw the part so injured: he occasionally moves his limbs; he appears, in short, as if in a sound heavy sleep like that of a drunken man. The breathing is not stertorous, but generally quite natural; the pupil is contracted and irritable; the pulse is sometimes unaffected, but in severe cases small and weak; there is nausea or vomiting, and the extremities feel cold. If the case is about to terminate fatally, the whole body grows rapidly cold, the pulse becomes irregular and weaker, the breathing short and interrupted, and the insensibility increases. In treating cases of concussion much caution is needed: till he is completely roused to his former state; but if, instead of being depressed, he remain stationary, no active means of any kind should be employed. HEAD, SIR GEORGE, deputy-knight marshal to her Majesty, was born at Higham, in Kent, in 1782, and is known as the author of various works of some literary repute; among others, his account of Forest Scenery and Incidents in the Wilds of North America, being a Diary of a Winter's Route from Halifax to the Canadas, during Five Months' Residence in the Woods, and the Borders of Lakes Huron and Simese.' Sir George had been engaged to superintend the commissariat duties of the British Settlement in North America for many years; and while on the Halifax station, engaged in that capacity, the above Diary was made, and published in 1829. Encouraged by the success which accompanied this work, he brought out his 'Home Tour through the Manufacturing Districts of England in the Summer of 1835;' his Home Tour through various Parts of the United Kingdom;' 'Memoirs of an Assistant Commissary-General;' and 'Rome, a Tour of Many Days.' He was also the translator of Cardinal Pacca's Historical Memoirs,' and the 'Metamorphoses of Apuleius,' which were published in 1850 and 1851. He was likewise an extensive contributor to the pages of the Quarterly Review; while his brother, Sir Francis Head, was the author of a very popular work known as the 'Bubbles of Nassau.' Sir George received the honour of knighthood in 1831; and died in 1855. HEAD'BOROW, a term applied by the Saxons to the head of the frank-pledge in boroughs. He was the chief of the ten pledges, as the other nine, being inferior pledges, were designated handborows. HEALTH, BILL OF, in Shipping, is the certificate of a consul as to the health of a crew when the ship has come from a suspected port. The names given to the documents representing the various degrees of health are a clean bill, a suspected bill, and a foul bill. Bill of Health, in the law of Scotland, is an application made to the Prison Board by a prisoner to be allowed to live away from the prison, of course under surveillance, on account of ill-health. This is sometimes allowed both in England and Scotland, but it is only in the latter country that the petition is called a bill of health. HEALTH, PUBLIC. [TowNs, HEALTH OF.] HEARNE, THOMAS, an eminent English antiquary, was born at White Waltham, in Berkshire, in 1678, where his father was the parish clerk. In 1692, under the patronage of Francis Cherry, Esq., of that place, with whom he had till then lived as a menial servant, he was placed at the free school of 207 HEARSAY HEART. 208 Bray, and subsequently, in 1695, at that gentleman's | artery, but which may rather be regarded as a series expense, was entered of Edmund Hall, Oxford. He of ventricles, the blood passes from behind forwards, became B.A. in 1699. In 1701 he received his first diverging into small streams, one of which flows to employ in the Bodleian Library. He was afterwards each of the antennæ, feet, &c. No distinct vessels can made janitor of the library, and in 1712 succeeded be detected in which these minor currents may run ; to the place of second librarian. In January, 1715, they seem simply to pass through the various tissues, he was elected architypographus and esquire bedel and, having arrived at their destinations, to form of civil law in the University, which post he held there into arches, and return and empty themselves with his under-librarianship till the month of Novem- into abdominal vessels, which may be regarded as ber following, when he resigned the bedel's place, veins, and through which the blood flowing from and soon afterwards his post in the Bodleian Library, before backwards is returned into the dorsal artery on account of the oaths to the government, which through the communications which exist between he could not conscientiously take. He continued a them at the posterior part. This is also the plan non-juror to the last, much at the expense of his of the circulating system which with various modiworldly interest. He died June 10, 1735. fications prevails in the arachnida and the lower crustacea. Hearne's publications were almost exclusively printed by subscription at Oxford, and are very numerous. Among the most valuable are-an edition of Livy, 6 vols. 8vo., 1708; the 'Life of Alfred the Great,' from Sir John Spelman's MS. in the Bodleian Library, 8vo., 1710; Leland's 'Itinerary,' 9 vols. 8vo., 1710; Leland's 'Collectanea,' 6 vols. 8vo., 1715; Camden's 'Annals,' in Latin, 3 vols. 8vo., 1717; History and Antiquities of Glastonbury,' 8vo., 1622; 'Robert of Gloucester's Chronicle,' 2 vols. 8vo., 1724; 'Peter Langtoft's Chronicle,' 2 vols. 8vo., 1725. HEARSAY. [EVIDENCE.] The simplest kind of a heart, forming a defined cavity, is found in some of the larger crustaceæ. In most of the mollusca the blood flowing through the branchial veins, instead of being poured directly into the ventricle, is received first into an auricle, presenting the first instance of a heart with more than one cavity. In most of the gasteropoda and pteropoda the auricle is single; in the bivalves the auricle is double. Among vertebrate animals the simplest form of heart is found in fish. They have a single auricle which receives the blood from the trunks of the veins HEARSE, a funeral carriage in or on which a of the whole body, and communicates with a single corpse is borne to its last resting-place. In England ventricle, which forces the blood into an arterial it is usually a closed carriage, decorated with plumes trunk with a contractile bulb. From this trunk all or feathers on the top and black drapery at the the branchial arteries arise, and, passing on each sides. On the occasion of public funerals, and gen-side in arches to the gills, divide there into capillary erally on the continent, the hearse is an open car on which is placed a bier with the coffin. HEART is the central organ of the circulation, and by its alternate contractions and dilatations is one of the principal powers by which the blood is moved through the bodies of the higher animals. branches. The blood thus aerated passes on, and the arches again unite into a common trunk the true aorta, which runs along the under surface of the spine, and sends the blood to all parts of the body. From these it collects again into the systemic veins, by which it is carried back to the auricle. The same type of formation is found in the reptiles which have gills. The simplest mode by which a distribution of nutritive fluid is effected, is by means of ramifications proceeding from the stomach or intestinal canal to In the air-breathing reptiles there is a single venvarious parts of the body, which occurs in the polyps, tricle from which arises a single aortic trunk, from infusoria, intestinal worms, echini, medusæ, and which proceed two pulmonary arteries, conveying that other zoophytes. In all these the digestive canal and part of the blood which is to undergo respiration to the circulating system form but one apparatus; the the lungs, whence it is returned by pulmonary veins. food, which in the higher animals requires a com- From the same aortic trunk four other arteries arise, plicated process of assimilation before it is fitted two of which, forming arches, unite to form the to move with the blood, is in them already adapted dorsal aorta, while the two uppermost are distributed for nutrition. In most of them currents can be seen to the head and upper extremities. From the terpassing in opposite directions along the canals open-minations of these arteries in all parts of the body ing into the digestive cavity, exactly like those well the blood is collected into large venous trunks, which known to exist in the stems of charæ, and probably produced by the motion of cilia which line the tubes, but are too minute to be discerned even with the microscope. In the annelida the circulation is carried on by means of two large vessels which alternately contract and expand, and thus carry the circulating fluid to all parts of the body. The first indication of an organ like the heart is seen in insects, which have a large vessel running along the back, divided by numerous constrictions into a series of communicating cavities, between which there are lateral openings through which the blood is received, and which are guarded by valves to prevent the blood from flowing out. Through this, which is commonly called the dorsal open into a double auricle, from which the aerated blood from the lungs and the impure blood from the system pass separately into the common ventricle, in which they are intimately mixed. Man, mammalia, and birds have a double circulation, to which some of the forms just described make very close approximations. The heart of man may be taken as the type of this circulation. It is of a somewhat conical form, having its base directed backwards towards the spine, and its point forwards, downwards, and to the left side, so that at each contraction it may be felt striking between the fifth and sixth ribs, about four inches from the middle line. It rests upon the diaphragm, or muscular partition between the chest and abdomen, and the surface upon which it lies is much flattened. It is firmly attached to the diaphragm at its right side, and behind by the inferior cava, which passes through that muscle, and above and behind it is fixed, though more loosely, to the upper and back part of the chest by the rest of its great vessels, which there pass out of the pericardium, and are united to the surrounding cellular tissue and organs. Everywhere else it is quite free and movable, though the range of its motions is limited by the pericardium, or membranous bag in which it is contained, and which closely surrounds it at all times. To examine the interior of the heart, it should be removed from the pericardium, and an incision should be made into the front of the right or front auricle, so that an angular flap may be cut out of its walls, and the whole view of the back part and sides of its interior may be exposed. There will then be seen, behind and to the right side, two large apertures; the upper leading to the vena cava superior, through which all the blood is returned from the head and upper extremities, and the lower leading to the vena cava inferior, by which all the blood is conveyed from the abdomen and lower extremities. These apertures will be seen to be surrounded by a few muscular fibres continuous with those of the auricle itself, and that of the inferior cava is partially guarded by a thin semi-lunar membranous fold, called the Eustachian valve, varying much in size, and often much torn. The left side of the cavity, on the partition which separates it from that of the right auricle, presents an oval depression (the fossa ovalis) surrounded by an elevated border, indicating the situation of the foramen ovale, through which, during the foetal state, the blood, which was prevented by the Eustachian valve from passing into the ventricle, was conveyed directly from the right into the left auricle, and thence into the left ventricle. Lastly, at the anterior and left angle of the cavity another and the largest aperture is seen, which leads into the right ventricle, and has attached to its sides a membranous curtain, by which it is occasionally closed, and which is called the tricuspid valve. to the whole interior circumference of which is attached the fold of membrane, strengthened by tendinous fibres, forming the valve. From the front and upper part of the ventricle a smooth short passage leads to the origin of the pulmonary artery, which is attached firmly to the dense ring to which many of the muscular fibres of the ventricle are affixed. At their union, and at the very orifice of the pulmonary artery, three little valves (the semi-lunar, sigmoid, or pulmonary valves) are seen, of a semi-lunar form, attached by the whole length of their convex edges to the walls of the artery, and hanging loosely in it with their free festooned edges directed upwards, inclosing behind them three small spaces, where the artery bulges somewhat outwards. These valves completely close the orifice of the artery inwards, so as to prevent any fluid from passing into the ventricle. The left posterior or aortic ventricle and auricle differ in no important particular from the right. The walls of both cavities on the left side and all the parts contained in them are thicker and stronger than those on the right; the orifice between them is guarded by a valve which has only two principal divisions, and is therefore called the mitral valve. The aorta proceeds upwards, and to the right side, then arches backwards and to the left, and, turning over the main air-tube of the left lung, passes down along the spine, at the lower part of which it divides into two large arteries (the common iliacs) which supply the pelvis and lower extremities. From the upper part of its arch it gives off the main trunks of the head and upper extremities in three large trunks that most to the right, called arteria innominata, is the common trunk which divides into the right carotid for the right side of the head, and the right subclavian for the right arm and side of the neck and chest. Next to it is the left carotid, and next the left subclavian, of which the distribution is similar to that of those on the right side. During life, the blood returning from the whole body by the veins which unite to form the two venæ cava enters the right auricle and gradually distends it, at the same time that the blood returning from the lungs by the pulmonary veins enters the left auricle and distends it. When completely filled, a kind of vermicular motion is seen commencing at the point of each auricle, which is rapidly propagated along their walls, and simultaneously empties the contents of the one into the right, and of the other into the left ventricle. The ventricles are no sooner completely filled than they contract suddenly and with much greater force than the auricles, and propel the blood into the pulmonary artery and aorta. From the aorta the blood is propelled into the arteries, through which it is distributed to all the body, and returned by the veins; but the veins of the intestinal canal and the organs connected with it unite into a large trunk, the vena portæ, which, instead of at once entering the heart with the others, passes into the liver, and there again divides into minute capillary vessels, from which the bile is secreted, and which pass into the ultimate divisions of a series of hepatic veins, which collect into three or four large trunks which open into the vena cava inferior just before it passes through the diaphragm Proceeding in the course of the circulation, a cut should be made from the right auricle through the aperture leading from it into the right ventricle, and along the front of the heart nearly to its apex, and then another from the end of the first upwards into the pulmonary artery, as it arises from the front and upper part of the ventricle. By raising the portion thus cut out, a complete view of the cavity of the right or pulmonary ventricle, and of its communication with the auricle, will be seen. The cavity of the right ventricle has a somewhat conical form, with its base uppermost, that part of its walls which is formed by the septum projecting somewhat into it. Its walls are rendered extremely irregular by prominent bands of muscular fibre. Here and there stand out short columns of muscle projecting into the interior, and pointing towards the right auricle; these are called columnæ carnex, and they have attached to their summits fine tendinous cords (chorda tendinex), which pass thence to be attached to the edges of the curtain-like membrane (the tricuspid valve) which guards the orifice between the auricle and ventricle. This orifice is of a broadly oval form, surrounded by a ring of firm dense tissue. to enter the right auricle. 211 HEART. HEART. 212 The accompanying fure represents a section of Blood that had been forced into them, and propel it the heart and lungs Thee & crosses the left in every direction, and that when elongated they lung and enters the left side of the heart. The line aran soorten and that when empty they remain B passes the right lung to the right side of the heart open and tabular. The chief effect of the action of Harvey considered the heart to be the sole agent this elasticity is the gradual conversion of the jetting by which the circulation is effected, but it is certain paisatie motion, which the blood receives from the that several other agents exercise auxiliary powers, forble and successive contractions of the ventricle, That the heart has, however, an influence on all into an even and steady current. parts of the circulation, is quite evident. In the We have said that the arteries are dilated slightly larger arteries its effect is seen in the increase of the by each column of blood poured out by the ventricles: current which it has set in motion, in exact coinci- from this arises their puise, which may be said to dence with the contraction of the ventricles; in the be owing to the dilatation of the arteries produced smaller ones, by the same increase at a scarcely by the wave which is propagated along the column appreciable interval; in the capillaries, by the of blood contained in them. The frequency of the occasional pulsatile motion which may be seen in paise depends entirely on the number of contractions them, when, after an animal has been largely bied, of the left ventricle in a certain time; and hence the its transparent parts are examined with the micro- varieties of frequent, slow, irregular, intermitting scope, and this though the heart is acting very pulses are entirely referrible to the heart. The size weakly. Lastly, in the veins we find its influence and degree of contraction of the artery produces the Heart and Lungs. fulness or smallness, the hardness or softness, and all the other characters which are determined by the touch rather than by mere counting. From the fact that the great chemical change by which heat is developed in the animal system takes place in the capillaries, it follows that their influence on the circulation is very considerable. They form a dense network of extremely minute tubes, in which the arteries seem to terminate and the veins to arise, for their delicacy prevents the possibility of discovering any such structure as could decide to which set of vessels they belong; and indeed it is only by observing that the currents of blood-globules pass in regular directions that we can prove that they are canals with definite membranous walls. When the circulation is examined in the web of the foot of a frog, or in the transparent parts of other animals, as the fins, tails, or lungs still exerted; for if the main artery and vein in al of fish, frogs, lizards, &c., we see a number of limb be exposed and isolated, and the latter be minute corpuscles coursing along in little streams, wounded, the flow of blood from the orifice may be exactly regulated by compressing the artery, that is, by preventing, to a greater or less extent, the blood from flowing to the vein with the impulse given to it by the heart. It appears also that, in addition to propelling the blood, the heart during its expansions draws up the blood, so that it acts both as a sucking and a forcing pump. From the heart the blood is poured into the arteries, a series of ramifying tubes through which the current is distributed, divided into a gradually increasing number of streams, which progressively diminish in size, till it arrives at a network of the most minute canals, the capillaries. The chief property of the arteries by which they affect the circulation is their extreme elasticity. It is by this that when dilated they contract on the in some parts in a confused multitude, as in the vessels which are sufficiently large to admit several to pass together, at others in only a single line, where the vessel is but little larger than the corpuscle itself. The currents run generally in the same direction in the same vessels, all tending to a larger branch, which may be regarded as the commencement of a vein, and setting out from the minutest termination of the artery. The capillaries are the most delicate of all organic tissues, measuring from 1-2000 to 1-5000 of an inch in diameter; they exist in all tissues of the body, varying in arrangement only in the greater or less closeness of the network which they form, and of which the meshes are in some organs so fine as not to exceed in width the diameter of the capillaries themselves, as is the case in the iris and lungs. It is through |