been translated into English. In the intervals of their publication she travelled extensively over Europe, and her experiences of the different countries she visited have been given in as many volumes. In 1839 she submitted to a dangerous operation on the eye, which for a time threatened to deprive her of sight; and to divert her mind she pursued her restless wanderings to the East, recording her adventures in the "Oriental Letters." Her mental temperament, early disappointments, and intellectual longings, contributed to render her life unhappy. In 1848 the death of an intimate friend oppressed her with a gloom which she sought to dispel by religious reading. Two years later she embraced the Roman Catholic faith, giving in one of her latest prose works, "From Babylon to Jerusalem," an account of her conversion. Finally in 1852, wearied with the world, she entered the mother house of the order of the Good Shepherd, at Angers. She has since devoted her life to the reformation of the outcasts of her own sex, and has published some religious poems.

HAHNEMANN, SAMUEL CHRISTIAN FRIEDRICH, the founder of the homoeopathic system of medicine, born in Meissen, Saxony, April 10, 1755, died in Paris, July 2, 1843. His father, a painter on porcelain, and a man of considerable acquirements, was his first instructor, but was prevented by poverty from giving him any better education than the elementary schools of his native place could afford. Young Hahnemann, however, evinced so much industry and intelligence that he was admitted free of expense into the high school of Meissen, whence, after a thorough instruction in Latin, Greek, and the chief modern languages, he repaired at the age of 20 to the university of Leipsic for the purpose of studying medicine. His means of subsistence having failed him, he devoted his leisure hours to teaching the languages, and to translating foreign medical authors into German. So energetic was his disposition, and so bardy his natural constitution, that, for the purpose of pursuing his literary labors, he was accustomed to sleep only every other night, a habit he persevered in for several years. The professors of the university, observing his zeal, gave him free access to their lectures. In 1777 he went to complete his studies at Vienna, where he came under the notice of Quarin, physician to the emperor, and chief physician to the hospital of Leopoldstadt, who intrusted him with the care of one of the hospital wards, and subsequently recommended him to Baron von Brückenthal, the governor of Transylvania, in whose family at Hermannstadt he remained as librarian and physician for nearly 2 years. In Aug. 1779, he took his degree of M.D. at Erlangen, presenting for the occasion his thesis entitled Conspectus Affectuum Spasmodicorum Etiologicus et Therapeuticus. After a brief residence in Hettstädt and Dessau, where he studied chemistry and mineralogy, and at Gommern near Magdeburg, where in 1785 he

was married, he settled in 1787 in Dresden, and soon secured a lucrative practice. He was fast achieving a reputation there, not only as a hospital physician and a general practitioner, but as a writer on medical science, when a distrust of the received system of therapeutics caused him to pause in his labors. In place of facts and laws, he complained that he found only hypotheses and theories, and to doubt succeeded complete discouragement. Finding that he could no longer conscientiously practise his profession, he returned in 1789 to Leipsic, where he resumed his chemical studies, and endeavored to support his family by translating English and French medical authors. At first he was obliged to struggle with poverty, and to endure the reproaches of his wife and children, who could not appreciate his motives in exchanging a lucrative profession for one so precarious. To add to his troubles, his children experienced severe attacks of illness, and he was obliged to minister to their relief according to a system in which he had ceased to place confidence. This circumstance, however, only stimulated his desire to establish a new system of therapeutics, the leading principle of which soon occurred to him. In 1790, while engaged upon a translation of Cullen's "Materia Medica," he was struck with the contradictory properties ascribed to Peruvian bark, and the various explanations given of its operation in intermittent fever. Dissatisfied with the latter, he resolved to try upon himself the effects of the medicine, and, after several powerful doses, discovered symptoms analogous to those of intermittent fever. The fact that a drug had produced upon a man in health the very symptoms which it was required to cure in a sick man immediately suggested to him the great law, Similia similibus curantur ("Like cures like"), which is the groundwork of the homoeopathic system. He nevertheless determined to test the principle fully before announcing it to the world, and did not hesitate to reduce his constitution to a permanent state of ailment, often at great personal risk, by experimenting upon himself with a variety of drugs. Similar results having been obtained in every instance, and also in the experiments tried upon his friends and children, he applied the new law to the treatment of the patients in the insane asylum at Georgenthal near Gotha, over which the duke of Saxe-Coburg-Gotha had appointed him, with complete success. From Georgenthal he proceeded in succession to Pyrmont, Brunswick, and Königslutter, effecting in each place remarkable cures. In 1796 he ventured, in a paper published in Hufeland's "Journal," to make his first public exposition of the similia similibus principle, which, if not its discoverer, he was the first to declare to be the leading principle in therapeutics. His suggestions were received with indifference or ridicule, and during the next 15 years, in the course of which he visited alternately Hamburg, Eilenburg, Wittenberg, Torgau, and finally Leipsic, he was the object of ceaseless attacks from those

whose interests were opposed to the innovations he sought to introduce into medical practice, the physicians and apothecaries in particular making war upon him without mercy. During this period he published a treatise on the efficacy of belladonna in the prevention and cure of scarlet fever, followed by Fragmenta de Viribus Medicamentorum Positivis sive Obviis in Corpore Sano (2 vols. 8vo., Leipsic, 1805), and "Medicine of Experience" (8vo., Berlin, 1806), all treating of the new doctrine. But in his "Organon of Rational Medicine" (8vo., Dresden, 1810), homœopathy first received its distinctive name, and was first reduced to a system and methodically illustrated. This work, of which many editions and translations in the principal European languages have since appeared, created a considerable sensation in Germany, and a bitter warfare was waged for upward of 12 years between the old and the new schools of therapeutics. About this time he fixed his residence in Leipsic, where, notwithstanding much opposition, he entered upon an extensive practice, and gathered about him many friends and disciples. During the prevalence of a malignant form of typhus in 1813, caused by the recent presence of the allied and French armies, the patients became so numerous that it was necessary to divide them among the physicians of the city. Of the 73 allotted to Hahnemann, and by him treated on the homoeopathic method, all recovered except one old man. But this fact only increased the enmity of his opponents; and by a combination among the apothecaries, who revived against him an old law which prohibited a physician from dispensing his own medicines, a practice Hahnemann had always followed, and which, on account of the interested motives of his adversaries, he was unwilling to relinquish, he was induced in 1820 to accept an asylum in Köthen, in the dominions of the duke of Anhalt. Leipsic subsequently repaired this injury by erecting a statue to him in one of the city squares. He encountered at Köthen the same hostility which had driven him from Leipsic, and such were the annoyances and insults heaped upon him that he rarely went abroad. The homoeopathic system was meanwhile making its way silently over Europe, and patients, many of whom were persons of distinction, repaired from all sides to receive the advice of its founder. The importance which the petty town of Köthen thus acquired soon caused a reaction in his favor, and when, upon his marriage for a second time in 1835 with Mlle. d'Hervilly, a young French woman, and an enthusiastic admirer of his, he took his departure, it was deemed necessary to go secretly by night for fear the populace might insist upon detaining him. Repairing with his wife to Paris, he resided there in the active practice of his profession until his death, and had the gratification of hearing that a professorship of homœopathy was to be established at the university of Vienna, and that homoeopathic hospitals were proposed in London, in Berlin, and many

German cities. In addition to the works previously mentioned, he published Materia Medica Pura (6 vols. 8vo., Dresden, 1811-21); "Chronic Diseases, their Peculiar Nature and Homopathic Cure" (4 vols. 8vo., Dresden, 1828–80); pamphlets on Mercurius Solubilis, the method of detecting adulteration in wine, &c.; a num ber of minor medical works which first appeared in a collected form in 1829 (2 vols. 8vo., Leip sic); and many volumes of translations of Eng lish and French medical and miscellaneous works. Several of his most important works have been translated into English and publish ed in New York by Prof. C. J. Hempel of Philadelphia. (See HOMOEOPATHY.)

HAIL, the watery vapors of the atmosphere congealed in icy masses called hailstones, and precipitated upon the earth. The phenomenon is not, like rain falling in frozen drops, and like snow, dependent upon coldness in the lower strata of the atmosphere; but it most frequently appears in the spring and summer months, and in the warmest part of the day, rarely st night. It is, moreover, usually accompanied by violent commotions in the atmosphere, vivid lightnings and heavy thunder, and clouds of intense blackness, phenomena that attend the coming together of bodies of air of different temperatures. As the storm gathers, rain often falls for a short time, and then suddenly changes to hail. The clouds from which the hailstones are precipitated are of a reddish bronze, sometimes of sea-green color, apparent ly not very high, of very irregular outline, as well upon their edges as upon their lower sur face. For some minutes the hailstones rattle down with great violence, rebounding from the earth and rapidly covering it with icy balls, sometimes to the depth of several inches. The storm then suddenly lulls for a short time, and soon sets in again with rain or snow, the temperature having considerably fallen. The size of the hailstones is generally from of an inch to an inch in diameter; but many authentic cases are cited of hailstones of 3 inches diame ter, and some of 4 inches; and a few cases are on record, which cannot well be questioned, of stones much larger than these. Thus the abbé Maury, in a paper read before the royal society in 1798, speaks of their falling in Germany from inch in diameter to the weight of 8 lbs. Matteucci, describing the storm of July 24, 1832, at Tussi, certifies positively to their having fallen of the weight of 14 lbs., and states that it appears certain that one was found which weighed 14 lbs., and that another forced its way through the roof of a house. But the statement of Heyne in his historical and statistical tracts on India, when speaking of the masses of hailstones that have fallen in the Mysore country, that "in the latter part of Tippoo Sultan's reign it is on record and well authenticated that a piece fell near Seringapatam of the size of an elephant," must be received with some allowance for oriental exaggeration. The devastation caused by hailstones is at

times very serious. Sir Robert Wilson describes a terrible thunder and hail storm which occurred at Marmorice bay, Asia Minor, while the British fleet were at anchor there in Feb. 1801. It continued at intervals two days and nights. The hailstones, as large as walnuts, fell in showers, pouring down from the mountains, and deluging the camps with a torrent of them two feet deep. In France, a country peculiarly subject to the most violent hail storms, a district comprising 1,000 parishes has been ravaged by a single storm, and damage has been caused to the amount of $5,000,000, as was the case in 1788. Arago states that in 1847 the crops in two small agricultural districts in Burgundy were injured by hail to the amount of 1,500,000 francs. Instances are recorded of domestic and wild animals being destroyed in large numbers by the hailstones. A little after midnight of March 28, 1834, in a hail storm which continued only 10 minutes, at Jackson, La., great numbers of cattle were killed by the hailstones, and much damage was done to the houses and woods. Darwin makes mention of many wild deer being killed in a hail storm at night in Buenos Ayres, one man finding and bringing in 13 carcasses, and another 7. Ostriches and other birds also were destroyed. The velocity of the fall of hailstones is usually much less than should be due to bodies of their density, which is somewhat less than that of water falling from altitudes of several thousand feet; and several ingenious theories have been devised to account for this-as the resistance occasioned by upward currents of air, such as perhaps always accompany the phenomenon. Prof. Olmsted, in his paper upon the phenomena and causes of hailstones, in vol. xviii. of the "American Journal of Science" (1830), supposes that the true reason of the small velocity is the retardation occasioned by the nucleus continually taking up in its descent accessions of vapor, which are in a state of rest. But in a hail storm in India described by Dr. A. T. Christie in the "New Edinburgh Philosophical Journal," and cited by Prof. Olmsted in vol. xx. of the "American Journal," p. 374, it is stated that the heavy clouds appeared almost to touch the tops of the tents; whence it would seem that the stones do not necessarily require a great elevation for their production. Their descent, however, is by no means always unaccountably slow. Dr. Malcolmson describes another storm which occurred in India in 1831, when the stones "ploughed up a gravel walk like musket balls, and passed through glass windows, making round holes, but not cracking them." These hailstones are described as flat; more commonly they are spheroidal, sometimes pointed, and sometimes ragged. When broken open, they generally present an outer homogeneous coating of opaque ice, or a succession of opaque and transparent layers of ice, enclosing a central nucleus of spongy but somewhat hardened snow. They have also been seen of radiated structure. Hail storms are of more

frequent occurrence in the temperate than in tropical climates, and in the polar regions they are scarcely ever heard of. Some countries are particularly subject to them; none more so perhaps than the south of France, where in 1829 an insurance company was organized to protect against their ravages. In that country the practice was introduced in the last century, and has since been extended into Germany, Switzerland, and Italy, of setting up in the vineyards long pointed poles or hail rods (paragrêles), with the view of thereby drawing off the electricity which is developed in the hail clouds, and thus disarming the cloud, on the supposition that the hail was, like the lightning, a result of its electrical condition. This was originally a hypothesis of Volta, who explained the origin of hail by the snowy nucleus being alternately attracted and consequently passed between two clouds charged with opposite kinds of electricity, and gradually accumulating more moisture and bulk. The theory has found little favor with scientific men, but the paragrêles have been used with great confidence in their affording valuable security; and in 1847, when an application was made to Arago to recommend some means of protection against the hail storm, he proposed the use of balloons communicating with the earth by a metallic wire in order to discharge the electricity of the clouds, as if this were the cause, and not merely a concomitant, of the production of hail.-It appears that countries may vary at different periods in the conditions favorable or opposed to the occurrence of hail. Thus at Havana, as stated by Humboldt, and confirmed by the records of the date of his observations, hail fell only once in 15 or 20 years. M. Poey of that city, in a paper presented to the American association in 1854, stated that from 1828 to 1846 no hail fell there, but every year afterward excepting 1850, and including 1854, it was observed; and the maximum fall of hail in the island, it was remarked, did not occur in the hottest months, but in March and April. Hail storms are generally limited to a district of moderate area, though they often extend many times as far in length as in breadth. The memorable storm of July, 1788, passed over France in two parallel lines from S. W. to N. E.; one line extended about 500 miles in length, and the other about 600 miles; the mean breadth of each was only about 9 miles, and the interval between them, in which the rain fell in torrents, was 15 miles. The same cloud has been observed to shed rain in one portion, while hail was falling from another part of it. The cause of hail storms is assigned by Prof. Olmsted, in the paper already noticed, to "the congelation of the watery vapor of a body of warm and humid air, by its suddenly mixing with an exceedingly cold wind in the higher regions of the atmosphere." If a current of air in the upper regions of the atmosphere and in high northern latitudes were moving in a southerly direction, it might carry with it over many degrees of latitude its low tem

perature, while another from the south might convey in the opposite direction the heat and moisture it acquired in the tropics. Should these meet, similar phenomena to those exhibited by hail storms might well be expected to occur a rush of opposite and violent winds, the formation of dense clouds and the condensation and precipitation of their moisture, violent electrical excitement with terrific discharges of thunder and lightning, and soon after a great reduction of temperature upon the surface by the descending of the cold air of the upper current. The extremely low temperature of this current would cause the congelation as well as condensation of the watery vapor, and the particles of snow forming intensely cold nuclei would, as they fell, condense more moisture, which, instantly becoming solidified upon their surface, would add continually new layers of ice to their bulk. Currents of air of very different temperatures are more likely to come together in the temperate zones than in the torrid or the frigid zones; and it is in the first named, as already observed, that hail storms are most frequent. The conditions are favorable for their occurrence in the tropics in the vicinity of high mountains, and hail storms are more commonly encountered there in such situations. Southern France, so peculiarly exposed to them, is a hot and humid region situated between the Alps and the Pyrénées, the sources of the cold blasts. Mr. William C. Redfield advocated the opinion that the hot and cold airs are intermingled by a vortex or whirlwind in the atmosphere, or spout as it is sometimes called, connecting above with an overlying stratum of unusually cold air. A portion of this probably descends outside the vortex, and near the surface of the earth is pressed in and interlaminated with the layers of warm and moist air drawn in together with it. The moisture condensed by the chilly airs congeals in drops, which are whirled around in the vortex and swept upward, passing through layers of various degrees of temperature, and receiving in some of them accessions of moisture, which are converted in the coldest into successive icy coatings. Reaching the upper stratum, the low temperature they there encounter prepares them to receive new accessions in their fall to the earth. In the tropics it is rarely the case that a stratum of sufficiently low temperature to produce hail comes so near the lowest layers that a vorticular communication can be established between them, and hence the rarity of hail storms in these regions.

HAILES, LORD. See DALRYMPLE, SIR DAVID. HAI-NAN, a large island of China, lying S. of the province of Quang-tung, of which it forms part; pop. estimated at 1,500,000. It is separated from the continent by a channel 15 m. broad, and difficult of navigation even for junks. It is situated between lat. 18° 10′ and 20° N., and long. 108° 20′ and 111° E.; length 185 m., breadth 90 m. The E. coast is steep and rocky; the N. W. coast is unapproachable because of

sand banks; but the S. coast is indented with several commodious and safe harbors. The interior of the island is mountainous and barren, but the low lands near the sea are fertile and well cultivated. The principal productions are rice, sweet potatoes, sugar, tobacco, fruits, medicinal plants, sandal wood, braziletto, ebony, dye woods, and wax. There are valuable fisheries off the coast. The inhabitants of the maritime districts are mostly the descendants of Chinese settlers, but the interior is occupied by a distinct race, who claim to be independent of the Chinese government, and are supposed to be aborigines. These people are described as cheerful, amiable, cleanly, and industrious. Hai-nan is divided into 13 districts, whose respective capitals are all on the coast, and some of which are said to contain from 80,000 to 90,000 inhabitants. The metropolis of the whole island is Kiang-chow-foo, the port of which was opened to European shipping by the treaty of Tien-tsin (Aug. 1858).

HAINAUT, or HAINAULT (Flem. Henego wen; Germ. Hennegau), a province of the kingdom of Belgium, bounded N. by West and East Flanders and Brabant, E. by Namur, and S. and W. by France; area, 1,435 sq. m.; pop. in 1856, 769,841. It is traversed by the rivers Sambre, Scheldt, Dender, Haine, from which the province received its name, and by several cahals. It is very hilly in the S. E., but in other parts generally level. The soil, except in the arrondissement of Charleroi, is fertile. The mineral productions are coal, iron, lead, slates, marble, building stones, and limestone. The chief crops are wheat, barley, oats, rye, flax, beans, hemp, hops, potatoes, tobacco, and chicory. Horned cattle, sheep, and horses are reared

the latter valued as draught animals. There is also abundance of poultry, game, and bees. The inhabitants generally follow agriculture and cattle rearing, but they manufacture hardware, glass, woollen and linen_goods, porcelain, pottery, bricks, lace, and Brussels carpets. The principal exports are coal, iron, and lime. The province is traversed by good roads and railroads, the great lines being the Brussels and Namur and the Brussels and Valenciennes, beside several branch railroads. The chief towns are Mons, the capital, Tournay, Ath, Soignies, Charleroi, and Thuin. Hainaut was ruled by the counts of Hainaut in the 9th and 10th centuries, and subsequently attached in turns to the dominions of the counts of Flanders, the dukes of Burgundy, and the house of Hapsburg; since which time it has shared the fate of the other Belgic provinces.

HAIR, an elongated, more or less cylindrical epidermic appendage, analogous to the feathers of birds and the scales of reptiles. Its essential structure consists of an assemblage of epidermie cells at the bottom of a flask-shaped follicle in the substance of the skin, supplied with blood by vessels distributed to its walls; it is made up of a root, from which the hair is developed, and a stem or shaft continuous with it. The root

exhibits a bulbous enlargement, which, with the lower part of the stem, is enclosed in an inversion of the epidermis, having an outer or cellular and an inner or fibrous layer, formed of granular cells; each hair follicle is implanted in a depression in the dermis, between whose epidermic lining and the stem is a space into which the canals of sebaceous follicles frequently open, and in which entozoa are often developed; the inspissated sebaceous secretion forms the scurf at the roots of the hair; the follicle penetrates sometimes of an inch, reaching on the head, face, and pubis the subcutaneous areolar tissue, but generally is imbedded in the substance of the true skin. The bottom of the follicle is occupied by a papilla upon which the hair rests, a compound cellular vesicle, the true germ of the hair. The stem is composed of a cortical investing horny layer of scales, arranged in an imbricated manner, a softer medullary or pith-like substance in the centre, and a fibrous intermediate portion constituting of the bulk of the hair; the last two are by Carpenter considered as forming together the medullary substance. The growth of hair takes place at the root by the development of new cells at the bulb, the old being pressed forward by the new or becoming elongated in the stem. Hairs are very rarely cylindrical, but generally elliptical and flattened in proportion to the curl or crispness; the size is greatest toward the lower third, the root being smaller and the end terminating in a point. The hairs of the head are the longest, those of the beard the thickest, and those of the general surface the finest; among women the hair has been known long enough to fall below the feet, and the beard of man occasionally reaches to the waist; frequent cutting and shaving of hairs increase their thickness, but not necessarily their number. Hairs are observed in the foetus as early as the 3d or 4th month, in the order of follicle, bulb, and hair; from the resemblance of the mucous membranes to the skin, it is not surprising that hairs are sometimes developed on the conjunctiva of the eye, in the intestines, ovaries, &c.; they are frequently found in encysted tumors and in other inversions of epidermic structure. Hairs may be transplanted, and will contract organic adhesion in the new tissues; according to Eble, a hair which has reached its full development becomes contracted just above the bulb and falls off. In vigorous health the hairs are thick and firmly set in the skin; in debilitated persons they fall out spontaneously or with very slight force; in the latter case the bulb generally alone comes away, the sheath and germ remaining behind, and capable of reproducing the hairs under proper treatment or favorable circumstances; even when the entire follicles are removed, it is possible that new ones with their germs may be formed; new shafts are constantly in process of formation, as is shown by the short and pointed hairs on the scalp of old persons. The nutrition of hairs is effected through vessels in close contact with their tissue, with

out entering into their structure; so that causes affecting the general health, and especially the condition of the skin, act powerfully upon the nutrition of the hair; the premature baldness and grayness of the Americans as a people is in great measure owing to the non-observance of hygienic rules, and to excess of mental and physical labor in a climate foreign to the race. Hairs are distributed over the entire surface of the human body except the palms, soles, and terminal joints of the fingers and toes; but for special purposes most abundantly on the scalp, brows, edge of the lids, pubis, chin, cheeks, armpits, chest, and entrance of the nose and ears. In these situations the number varies according to temperament, age, health, and sex. According to Withof, the quarter of a square inch contained 293 hairs on the head, 39 on the chin, 23 on the forearm, 19 on the back of the hand, and 13 on the front of the thigh; in the same extent he counted 147 black, 162 brown, and 182 flaxen hairs, showing the comparative fineness. Long and strong hairs are often found growing from moles and nævi in various parts of the body. The hair generally grows in an oblique direction on account of the way in which the follicles are placed; these are sometimes placed wrongly on the scalp, causing much trouble to anxious mothers in regard to this head ornament in their children; perseverance will generally bring the refractory locks into the desired direction. From contraction or corrugation of the skin from cold, fear, or other causes, the hair, especially on the head, becomes partially erect, though it can never stand on end "like quills upon the fretful porcupine." The color of the hair depends partly on the presence of pigment granules, and partly on the existence of numerous minute air spaces which cause it to appear dark by transmitted light; its intensity generally bears a close relation to the color of the iris and the skin; in albinos and in gray-haired persons the coloring matter is deficient or absent. Long contact with chlorine decolorizes hair; and the undoubted fact that hair may turn white in a short time under the influence of strong emotions is doubtless to be explained by some chemical action upon the oily coloring matter, as suggested by Dr. D. F. Weinland, and more fully explained in the article FEATHERS. The turning gray of the hair is no sign of its loss of vitality, as hair of this color often grows for years as vigorously as the darker hued. Hair is remarkable for strength, elasticity, and durability, the first depending on its fibrous structure and the last two on its horny nature; a single hair will bear a strain of 1,150 grains, and might sustain the sword of Damocles. Hairs will endure not only during a long life, but will grow after death, and last for centuries; it is well known that hairs, especially of cats and other animals, become electrical by rubbing; the hygroscopic property of hair has been painfully manifested to many a beau and belle whose rebellious locks have refused to retain their ar