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.situated, and exceeding beautiful. It is 12 miles N, W. of Rot-terdam, and 32 S. W. of Amsterdam .

IIAGUENAU, a town of France , in the department of theLower Rhine, anciently an imperial town.

HAIL , in natural history, a meteor generally defined frozenrain, but differing from it in that the hailstones are not formed ofsingle pieces of ice, but of many little spherules agglutinated to-gether. Neither are these spherules all of the same consistence ;some being hard and solid like perfect ice ; others soft, and mostlylike snow hardened by a severe frost. Sometimes the hailstonehas a kind of core of this soft matter; but more frequently thecore is solid and hard, while the outside is formed of a softer mat-ter. Hailstones are of various figures ; some round, others pyra-midal, crenated, angular, thin, and fiat, and some stellated, withsix radii like the small crystals of snow. Natural historians re-cord various instances of surprising showers of hail, in which thehailstones were of extraordinary magnitude. Mezeray, speakingof the war of Lewis XII. in Italy , in 1510, relates, that there wasfor some time a horrible darkness, thicker than that of night;after which the clouds broke into thunder and lightning, amithere fell a shower of hailstones, or rather (as he calls them) peb-ble-stones, which destroyed all the fish, birds, and beasts, of thecountry. It was attended with a strong smell of sulphur; and thestones were of a blueish colour, some of them weighing 100 lb.Iiist. de France , Tom. II. p. 339- At Lisle in Flanders, in 1686,hailstones fell of a very large size; some of which contained inthe middle a dark brown matter,, which, thrown on the lire, gavea very great report. Philos. Trans. No. 203. Dr. Flalley andothers relate, that in Cheshire, Lancashire , &c. April 29, 1697, athick black cloud, coming from Caernarvonshire , disposed the va-pours to congeal in such a manner, that for about the breadth oftwo miles, which was the limit of the cloud, in its progress for 60miles, it did inconceivable damage ; not only killing all sorts offowls and other small animals, but splitting trees, knocking downhorses and men, and even ploughing up the earth ; so that thehailstones buried themselves under ground an inch or an inch andhalf deep. The hailstones, many of which weighed five ouncesand some half a pound, being five or six inches about, were ofvarious figures: some round, others half round ; some smooth,others embossed and crenated : the icy substance of them wasvery transparent and hard, but there was a snowy kernel in themiddle of them. In Hertfordshire , May 4, 1697, after a severestorm of thunder and lightning, a shower of hail succeeded, whichfar exceeded the former: some persons were killed bv it, theirbodies beat all black and blue ; vast oaks were split, and fields ofrye cut down as with a scythe. The stones measured from ten tothirteen or fourteen inches about. Their figures were various,some oval, others picked, some flat. Philos. Trans. No. 229.On the tops of mountains hailstones, as well as drops of rain, arevery small, and continually increase in bulk till they reach thelower grounds. It would seem, therefore, that during their pas-sage through the air, they attract the congealed vapour which in-creases them in size; or that the vapour they meet with is con-cealed on them as they fall. Some modern philosophers .ascribe.the formation of bail to electricity. See Metf.oroi.ogy.

IIAI HURON, a strong town in Wirtemberg , 5 miles N. E.of Stutgard.

HAINAN, one of the most considerable islands of Asia , sub-ject to China , and belonging to the province of Quang-ton. itbos on the N. the province of Quang-si; on the S. the channelbetween the bank Paracel and the E. coast of Cochin-China ; onthe \V. the same kingdom and part of Tong-king; and on the E.the Chinese sea. Its extent from E. to W. is between 60 and 70leagues, and from N. to S. 45 ; and about 480 miles in circumfer-ence. Kiun-tcheou-fou is the capital. Hainan lies near San-cian,between 18° and 20° Lat. N.

HAINAULT, a province of the Netherlands , formerly divid-ed between France and Austria , but now wholly belonging toFrance . It was bounded on the S. by Champagne and Picardy ;and extended from N. to S. about 45 miles, and about 48 fromE. to W.

HAINBURG, or HAIMBURG, a town of Austria , on theDanube, 8 miles W. of Presburgh, and 20 S. S. E. of Vienna .

HAIR, {Jmt, Saxon,] 1. One of the common teguments ofthe body. It is to be found upon all tire parts of the body, except i

the soles of the feet and palms of the hands. When we examinethe hairs with a microscope, we find that they have each a roundbulbous root, which lies pretty deep in the ikin, and which drawstheir nourishment from the surrounding humours: that each hairconsists of five or six others, wiapt up in a common tegument ortube. Hairs ordinarily appear round or cylindrical ; but the mi-croscope also discovers triangular and square ones; which diversityof figure arises from that of the pores, to whic h the hairs alwaysaccommodate their form. Their length depends on the quantityof the proper humour to feed them, and their colour on the qualityof that humour : whence, at different stages of life, the colourusually differs. Their extremities split into two or three branches,especially when kept dry, or suffered to grow too long; so thatwhat appears only a single hair to the naked eye, seems a brushto the microscope. The hair of a mouse, viewed by Mr. Dur-ham with a microscope, seemed to be one single transparent tube,with a pith made up of fibrous substances, running in dark lints,in some hairs transversely, in orders spirally. The darkec^nedul*lary lines, he observes, were small fibres convolved, and lymgcloser together than in the other parts of the hair. They run fromthe bottom to the top of the hair ; and he imagines, may serve tomake a gentle evacuation of some humour out of the body. Hencethe hair of hairy animals, may not onlv serve as a fence againstcold, &.c. but as an organ of insensible perspiration. When 3hair is drawn between the fingers from the root towards the point,scarce any friction or resistance is perceived, and no noise isheard ; but if it be passed in the same manner between the ting er5from th.e point towards the root, a resistance-is felt, a tremulousmotion is evident to the touch, and a noise may lie distinctlyheard. It is obvious therefore, that the texture of the surface ofhair is not the same from the root towards the poirt, as it is fromthe point towards the root. These observations are equally app* 1 "

cable to the filaments of wool. The ancients held the hair a sort

of excrement, fed only with excremoutitious matters, and no pro-per part of a living body. They supposed it generated of the fu-liginous parts of the blood, exhaled by the heat of the body to thesurface, and there condensed in passing through the pores;and that hair dees not feed and grow like the other parts, by ajuice circulating within it; but, like the nails, byjuxta-position.But the moderns are agreed, that every hair properly and trulylives, and receives nutriment to fill it like the other parts ; whichthey prove hence, that the roots do not turn grey in aged personssooner than the extremities, but the whole changes colour at once,which shews that there is a direct communication, and that all tl> eparts are affected alike. In strict propriety, however, it must beallowed, that the life and growth of hairs is of a different kind fromthat of the rest of the body ; and is not immediately derivedtherefrom, or reciprocated therewith. It is rather of the natureof vegetation. They grow as plants do, or as some plants shootfrom the parts of others ; from which though they draw theirnourishment, yet each has, as it were, its distinct life and economy-They derive their food from some juices in the body, but notfrom the nutritious juices of the body ; whence they may h' ethough the body be starved. Almost the only disease of the hair,besides the remarkable one called Plica Polonica, is baldness, orits falling off. For this many remedies have been recommence:»but scarce any of them can be depended upon. The juice of bur-dock, and the lixivial salts of vine-ashes, are said to be efficacious,also the powder of hermodactyls, and the decoction ot h°- K "wood, borne authors have given instances of the hair changmgbin a short time, its colour, through grief, a fright, &c. &c. I' rcquent cutting the hair is very beneficial to the ears, eyes, nay,to the whole body : and, if the head he wa-hed or immersed ( j al 7in cold water, it will be found an excellent preventive of jierioccal head-achs. Persons subject to delluxions i f humours from ^head, to weak eyes and similar complaints, will derive great b ent ‘fit from shaving the head at certain intervals ; as this is the moseffectual mode of opening the pores and promoting perspirati 011 -There is no clanger of contracting cold from washing or exp? 81 . 1 !®the head, after being rubbed dry, to the open air : and this tu \objection should influence only the conduct of those wlio, troirWft^norance or prejudice, carry all their exhaled impurities on ■surface of the skin, and especially oh the head, for a successionyears. Thus, perhaps, arise many states of intellectualment, the source of which is seldom suspected. Besides, c'R'“