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duced, will move westward. Yet in either case the motion is soslow, that the most superficial observers cannot help taking noticeof a considerable resistance in the atmosphere. That when twostreams of air are thus driven against each other, the space wherethey meet must become highly electrified, is as plain as that anelectric globe must be excited when friction is applied. It is true,as the substances here to be excited are both electrics per se, itmay be objected, that no electricity could be produced ; for wecannot excite one electric by rubbing it with another. Yet it isobserved, that glass may be electrified by blowing strongly uponit, or by the explosion of cannon ; and even when glass is stronglypressed upon glass, both pieces become electrified as soon as theyare separated. When glass is rubbed upon glass, no attraction ngrrepulsion can be perceived, nor is any sign of electricity observedon bodies brought near to it; yet a very bright electric light alwaysSppears on the glasses, and a phosphoreal smell is felt; whichshews, that though the electricity does not fly out through the airin the usual way, yet the fluid within the glass is agitated; andthere is little reason to doubt, that any conducting body enclosedwithin the substance of the glass would be electrified also. Thevapours, therefore, which are the conducting substances ;r> theatmosphere, become immediately electrified in consequence of thepressure above mentioned, and all the plmiomenaof lightning andthunder, take place. In like manner, bv the struggle of two otherwinds as well as those of the E. and \Y. may a thunder-storm beproduced. Thunder is frequently productive of beneficial effectson animal and vegetable nature; as its violent concussions contri-bute to disperse the noxious vapours collected in the atmosphere,during sultry and dry summers: it may also be regarded as aprognostic of the weather. Bradley remarks, thatfrequent thunder,without lightning, is generally followed by tempestuous winds ;but, in the contrary case, it predicts copious and sudden showers.With a view to prevent fatal accidents, during violent thunder-storms, the erection of conductors has been strongly recommended.For the same purpose the electrical kite may be usefully employed ;but it requires to be managed with great precaution. See Elec-tricity.

THUNOE, an island of Denmark, between Jutland and the isleof Samsoe. Lon. 10. 19. E. Lot. 55. 1 N.

THUR, a hill of Arabia, near Mecca . There is a care in it,where Mohammed concealed himself along with Abu Beer, awhole night, when the Koreish were in pursuit of him, and verynarrowly escaped being taken.

THURGAU, a territory of Switzerland , formerly alandgravate;bounded on the N. by Suabia and the lake of Constance ; E. bythat lake; S. by St. Gall ; and W. by tiie cantons of Zurich andSchaffhausen .

THURINGIA , in ancient geography, the country of the an-cient Thuringi, was formerly a kingdom , afterwards a county,then a landgravate, and was governed by its own princes formany ages, till 1124, when it devolved to the marquis of Misnia ,and, with that country, afterwards to the duke of Saxony .This country is seventy-three miles in length, and as much inbreadth.

Thuringia , in modern geography, a division of Upper Saxony.It is a fertile tract, abounding in corn, wheat, black cattle, sheep,and horses. Erfurt is the capital .

THURLOE, John, an English statesman under OliverCromwell , was bom at Abbots lloding in Essex, in 1016, of• which parish his father was rector, and was educated to the studyof the law. In 1648 he was made receiver of the cursitoryfines. When Oliver Cromwell assumed the protectorship, hebecame secretary of state; in 1655, he had the care and chargeboth of foreign and inland postage ; and was afterwards sworna member of the privy council. He was continued in the sameoffices under Richard Cromwell , and until measures were takenfor the Restoration ; when he made an oft'er of his servicesto that end, which, however, was not accepted. May 15th,1660, he was committed to the custody of the serjeant at armson a charge of high treason; but being soon released, lie re-tired to Great Milton, in Oxfordshire : and though he was after-wards often solicited by Charles II. to engage in the administrationof public business, he declined the offers. He died in 1663 ; andwas a man of an amiable private character, who in the highest•f bis power exercised Ml possible moderation towards persons

of every party. The most authentic testimony of his abilities ishis vast*collection of state papers, in 7 vols. folio.

THURSO, a borough or barony in Scotland , 42 miles N. N.E. of Dornoch.

THUS, Frankincense, a solid brittle resin , brought to us inlittle globes or masses, of a brownish or yellowish colour on theoutside, internally whitish or variegated with whitish specks. It issupposed to lie the produce of the pine that yields the commonturpentine, ar.d to concrete upon the surface of the terebinthinatejuice soon after it has issued from the tree.

Thus, in sea-language, a word used by the pilot in directingthe helmsman or steersman to keep the ship in her presentsituation when sailing with a scant wind, so that she may notapproach too near the direction ot the wind, which wouldshiver her sails, nor fall to leeward, and run farther out of hercourse.

THYMBRA, Mountain-Hyssop ; in botany, a genus ofplants of the class didynamia, and order gymnospermia ; naturalorder, Verticillata:. Calyx sub-cylindrical, two-lipped, scored oneach side with a villose line; style semibifid. There are threespecies.

THYMUS, in anatomy, a gland, which in infants is very re-markable ; it is situated in the upper part of the thorax imme-diately under the sternum, ar.d lies upon the pericardium, and onthe trunk of the aorta and of the vena cava. See An atomy.

Thymus, Thumb ; in botany, a genus of plants of the classdidynamia, and order gymnospermia; natural order, Verticil-lata:. Calyx bilabiate, its throat dosed with soft hairs. There aretwenty-two species; of which two only are natives of Britain .

Til YNNUS, a genus of the hymenoptera order of insects.The generic character is, mouth horny, with an incurved mandi-ble ; the jaw short and straight; lip longer than the jaw, mem-branaceous at the tip, and trifid, the middle-division emarginate ;tongue very short, involute; feelers four, equal, filiform; an-tenna: cylindrical, the first joint thicker. There are four spe-cies, three inhabiting New Holland, and the fourth is found inAfrica .

THYRSUS, in antiquity, the sceptre of Bacchus , and wherewiththey furnished the Menades in their Bacchanalia. The Thyrsiwere spears made wholly of wood, entwined with leaves and twigsof the vine and ivy.

Thyrsus, in botany, a mode of flowering resembling the coneof a pine. It is, says Linnscus, a panicle contracted into an ovalor egg-shaped form. The lower footstalks, which are longer, ex-tend Horizontally, whilst the upper ones are shorter and mountvertically. Lilac and butterbur furnish examples.

TIARA, an ornament or habit wherewith the ancient Persians covered their head ; and with which the Armenians and kings ofPcntus are represented on medals; these last, because they weredescended from the Persians .

Tiara is also the name of the pope’s tripple crown.

T1ARELLA, in botany, a genus of plants of the class rlecan-dria, and order digynia; natural order, Succulent *. Calyx five-parted ; corolla five-petaled, inserted into the calyx ; petals entire;capsule one-celled, two-valved, one valve larger. There are twospecies, viz. T. cordifolia, with heart-shaped leaves; and T. trifolia,the three-leafed tiarclla.

TIBER, a great river of Italy , much celebrated by the poets.It runs through the pope’s territories, passing by Perugia andOrvietto; and having visited Rome , falls into the Tuscan sea atOstia , 15 miles below that city.

TIBERIAS, in ancient geography, the last town of Ga-lilee, situated on the S. side of the lake Tiberias ; built by He-rod the Tetrarch, and named in honour of the emperor Tibe-rius ; 30 stadia from Ilippus. Jerome says its ancient name wasChennereth.

TIBET, or THIBET, a country of Asia , a part of IndependentTartary. See Tautary. It extends from the source of theIndus, to the borders of China , and from Hindooslan to thedeserts of Cobi, or Kobi; being 1500 miles long from E. to W.but of unequal breadth, the extent of which is not exactly known.It is called by the Tartars Barantola, and Tangoot; and by theChinese Tsang. It lies between 81° and 120° Lon. E. and be-tween 26* and 40® Lat. N. The climate is extremely cold andsevere. Even in the middle of April, the rivers and lakes are all

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