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The watchman gave so great a thump at my door, that I awaked at the knock. Tatler. Their thumps and bruises might turn to account, if they could beat each other into good manners. Addison. A watchman at midnight thumps with his pole. Swift. THUNBERGIA, in botany, a genus of plants belonging to the class of didynamia, and order of angiospermia. The calyx is double; the exterior one is diphyllous, and the interior one multipartite. The capsule is globose, beaked, and bilocular. There is only one species known, viz. T. Capensis, a native of the Cape of Good Hope. THUN'DER, n. s., v. n., Saxon Bunder, THUNDERBOLT, [& v. a. | Juneɲ; Swed. dunTHUN'DERCLAP, der; Belg. donder; THUN'DERER, Fr. tonnerre. The THUNDEROUS, adj. noise made by the THUN'DERSHOWER, n. s. explosion of electric THUNDERSTONE, fire in the clouds; it THUNDERSTRIKE, v. a. is sometimes used for both this and the lightning, or the entire electric storm; any loud or overpowering noise: to make such a noise; make thunder: as a verb active, to emit with noise or violence; to intimidate by noise: a thunderbolt, commonly means lightning; the bolts that fall from heaven; fulmination; denunciation: thunderclap, the explosion that produces thunder: thunderer, he who thunders: thunderous, producing thunder: the other compounds are of obvious meaning.

So soon as some few notable examples had thundered a duty into the subject's hearts, he soon shewed no baseness of suspicion. Sidney.

I remained as a man thunderstricken, not daring, nay not able, to behold that power.

Id.

So fierce he laid about him, and dealt blows, On either side, that neither mail could hold Ne shield defend the thunder of his throws.

Spenser.

The kindly bird that bears Jove's thunderclap, One day did scorn the simple scarabee,

Proud of his highest service, and good hap, That made all other fowls his thralls to be.

Id.

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As if 'twere forging thunderbolts for Jove. Denham.
His dreadful voice no more
Would thunder in my ears.
The thunder,

Milton.

Wringed with red lightning and impetuous rage,
Perhaps hath spent his shafts, and ceases now
To bellow through the vast and boundless deep. Id.
Look in and see each blissful deity,

How he before the thunderous throne doth lie. Id.
With the voice divine

Nigh thunderstruck, the' exalted man, to whom
Such high attest was given, a while surveyed
With wonder.
Jd. Paradise Regained.

Had the old Greeks discovered your abode,
Crete had n't been the cradle of their god;
On that small island they had looked with scorn,
And in Great Britain thought the thunderer born.
Waller.

The conceit is long in delivering, and at last it comes like a thundershower, full of sulphur and darkness, with a terrible crack. Stilling fleet.

When suddenly the thunderclap was heard, It took us unprepared, and out of guard. Dryden. When the bold Typheus Forced great Jove from his own heaven to fly, The lesser gods, that shared his prosperous state, All suffered in the exiled thunderer's fate. The Scipio's worth, those thunderbolts of war?

Who can omit the Gracchi, who declare

Oracles severe

Were daily thundered in our general's ear
That by his daughter's blood we must appease
Diana's kindled wrath.

Id.

Id.

Id.

Here will we face this storm of insolence, Nor fear the noisy thunder; let it roll, Then burst, and spend at once its idle rage. Rowe. An archdeacon, as being a prelate, may thunder out an ecclesiastical censure.

Ayliffe.

The most remarkable piece in Antonine's pillar is Jupiter Pluvius sending down rain on the fainting

army of Marcus Aurelius, and thunderbolts on his enemies; which is the greatest confirmation of the story of the Christian legion. Addison.

"Tis said that thunderstruck Enceladus Lies stretched supine.

Id.

In thundershowers the winds and clouds are oftentimes contrary to one another, especially if hail falls, the sultry weather below directing the wind one way, and the cold above the clouds another Derham's Physico-Theology. Like a black sheet the whelming billow spread, Burst o'er the float, and thundered on his head. Pope.

THUNDER is the noise occasioned by the explosion of a flash of lightning, echoed back from

His dreadful name late through all Spain did the inequalities on the surface of the earth, in

thunder,

And Hercules' two pillars standing near

Did make to quake and fear.

Ia.

If I had a thunderbolt in mine eye, I can tell who should down.

How dare you, ghosts,

Shakspeare.

Accuse the thunderer, whose bolt you know, Sky-planted, batters all rebelling coasts?

Fear no more the lightning flash, Nor the all-dreaded thunderstone.

Id.

Id. Cymbeline.

like manner as the noise of a cannon is echoed, and in particular circumstances forms a rolling lengthened sound.

It is universally allowed that the elevation of the electricity in different parts of the atmosphere is the cause of thunder, and, after what has been said on this subject in our article ELECTRICITY (see Index), it remains only to mention the theory by which some philosophers explain the

reason why rains are sometimes attended with thunder and sometimes not. In this part of Great Britain, and for a considerable way along the eastern coast, although thunder may happen at any time of the year, yet July is that in which it may almost certainly be expected. Its duration is of very uncertain continuance; sometimes only a few peals will be heard at any particular place during the whole season; at other times the storm will return at the interval of three or four days for five or six weeks, or longer; not that we have violent thunder in this country directly vertical in any one place so frequently in any year, but in many seasons it will be perceptible that thunder clouds are formed in the neighbourhood even at these short intervals. Hence it appears that during this particular period there must be some natural cause operating for the production of this phenomenon, which does not take place at other times. This cannot be the mere heat of the weather; for we have often a long tract of hot weather without any thunder; and besides, though not common, thunder is sometimes heard in winter. As therefore the heat of the weather is common to the whole summer, whether there be thunder or not, we must look for the causes of it in those phenomena which are peculiar to July, August, and September. Now it is generally observed, in the above-mentioned tract of country, that from April an east or south-east wind generally takes place, and continues with little interruption till towards the end of June. At that time, sometimes sooner and sometimes later, a west wind takes place; but, as the causes producing the east wind are not removed, the latter opposes the west wind with its whole force. At the place of meeting there is naturally a most vehement pressure of the atmosphere, and friction of its parts against one another; a calm ensues, and the vapors brought by both winds begin to collect and form dark clouds, which can have little motion either way, because they are pressed almost equally on all sides. For the most part, however, the west wind prevails, and what little motion the clouds have is towards the east, whence the common remark in this country, that 'thunder clouds move against the wind'. But this is by no means universally true; for if the west wind happens to be excited by any temporary cause before its natural period when it should take place, the east wind will often get the better of it; and the clouds, even although thunder is produced, will move westward. Yet in either case the motion is so slow, that the most superficial observers cannot help taking notice of a considerable resistance in the atmosphere. That when two streams of air are thus driven against each other, the space where they meet must become highly electrified, is as plain as that an electric globe must be excited when friction is applied. It is true, as the substances here to be excited are both electrics per se, it may be objected that no electricity could be produced; for we cannot excite one electric by rubbing it with another. Yet it is observed that glass may be electrified by blowing strongly upon it, or by the explosion of cannon; and even when glass is strongly pressed upon glass, both pieces become elecVOL. XXII.

trified as soon as they are separated. When glass is rubbed upon glass, no attraction nor repulsion can be perceived, nor is any sign of electricity observed on bodies brought near to it, yet a very bright electric light always appears on the glasses, and a phosphoreal smell is felt; which shows that though the electricity does not fly out through the air, in the usual way, yet the fluid within the glass is agitated; and there is little reason to doubt, that any conducting body enclosed within the substance of the glass would be electrified also. The vapors therefore, which are the conducting substances in the atmosphere, become immediately electrified in consequence of the pressure above-mentioned, and all the phenomena described under the various articles already referred to take place. In like manner, by the struggle of two other winds as well as those of the east and west, may a thunder storm be produced; but it is always necessary that the resistance of the air to the motion of the clouds should be very great, and nearly equal all round. For if the vapor should get off to a side, no thunder would take place; the electricity would then be carried off as fast as it was collected, and rain only would be the consequence, by reason of the electrified vapors parting with their latent heat. In fact, we very often observe, that in the time of rain the clouds evidently move across the wind, and the nearer their motion is to a direct opposition, the heavier will the rain be; while, on the other hand, if they move briskly before the wind, let the direction be what it will, the atmosphere soon clears up.

That rattling in the noise of thunder, which makes it seem as if it passed through arches, or were variously broken, is probably owing to the sound being excited among clouds hanging over one another, and the agitated air passing irregularly between them. The explosion, if high in the air and remote from us, will do no mischief; but when near, it may destroy trees, animals, &c. This proximity or small distance may be estimated nearly by the interval of time between seeing the flash of lightning and hearing the report of the thunder, estimating the distance after the rate of 1142 feet per second, or three seconds and two-thirds to the mile. Dr. Wallis observes that commonly the difference between the two is about seven seconds, which, at the rate abovementioned, gives the distance almost two miles. But sometimes it comes in a second or two, which argues the explosion very near us, or even among us. And in such cases, the Doctor assures us, he has sometimes foretold the mischiefs that happened.

The following general observations are made out from a comparison of a vast variety of more particular ones made in different places: 1. The air is almost always electrical, especially in the day time and dry weather; and the electricity is generally positive. It does not become negative unless by winds from places where it rains, snows, or is foggy. 2. The moisture of the air is the constant conductor of its electricity in clear weather. 3. When dark or wet weather clears up the electricity is always negative. If it has been very moist, and dries very fast, the electricity is very intense, and diminishes when

G

the air attains its greatest dryness; and may continue long stationary by a supply of air in a drying state from distant places. 4. If, while the sky overcasts in the zenith, only a high cloud is formed, without any secondary clouds under it, and if this cloud is not the extension of another which rains in some remote place, the electricity (if any) is always positive. 5. If the clouds, while gathering, are shaped like locks of wool, and are in a state of motion among each other; or if the general cloud is forming far aloft, and stretches down like descending smoke, frequently a positive electricity prevails, more intense as the changes in the atmosphere are quicker; and its intensity predicts the great quantity of snow or rain which is to follow. 6. When an extensive, thin, level, cloud forms and darkens the sky, we have strong positive electricity. 7. Low thick fogs, rising into dry air, carry up so much electricity as to produce sparks at the apparatus. If the fog continues round the apparatus without rising, the electricity fails. 8. When, in clear weather, a cloud passes over the apparatus, low and tardy in its progress, and far from any other, the positive electricity gradually diminishes and returns when the cloud has gone over. 9. When many white clouds gather over head, continually uniting with and parting from each other, and thus form a body of great extent, the positive electricity increases. 10. In the morning, when the hygrometer indicates dryness equal to that of the preceding day, positive electricity obtains even before sunrise. 11. As the sun gets up, this electricity increases; more remarkably if the dryness increases. It diminishes in the evening. 12. The mid-day electricity, of days equally dry, is proportioned to the heat. 13. Winds always lessen the electricity of a clear day, especially if damp; therefore they do not electrify the air by friction on solid bodies. 14. In cold seasons, with a clear sky and little wind, a considerable electricity arises after sunset, at dew falling. The same happens in temperate and warm weather. If, in the same circumstances, the general dryness of the air is less, the electricity is also less. 15. The electricity of dew, like that of rain, depends on its quantity. This electricity of dew may be imitated by electrifying the air of a close room (not too dry) and filling a bottle with very cold water, and setting it in the upper part of the room. As the damp condenses on its sides, an electrometer will show very vivid electricity. Such a collection of observations, to be fit for inference, requires very nice discrimination. It is frequently difficult to discover electricity in damp air, though it is then generally strongest; because the insulation of the apparatus is hurt by the dampness. To make the observation with accuracy requires a portable apparatus, whose insulation can be made good at all times. With such apparatus we shall never miss observing electricity in fogs or during snow. There is a very curious phenomenon which may be frequently observed in Edinburgh and other towns similarly situated. In a clear day of May an easterly wind frequently brings a fog with it, which advances from the sea in a dense body; and when it comes up the High Street it chills

the body exceedingly, while it does not greatly affect the thermometer. Immediately before its gaining the street, one feels like a tickling on the face as if a cobweb had fallen on it, and naturally puts up his hand and rubs his face. We have never found this to fail, and have often been amused with seeing every person rubbing his face in his turn. The same thing was ob served at St. Petersburgh in a summer's evening when a low fog came on about ten o'clock.

For the most part before thunder the wind is gentle or it is calm. A low dense cloud begins in a part previously clear: this increases fast in size; but this is only upwards, and in an arched form, like great bags of cotton. The lower surface of the cloud is commonly level, as if it rested on a glass plane. Soon after appear numberless small ragged clouds, like flakes of cotton teazled out. These are moving about in various uncertain directions, and continually changing their ragged shape. This change, however, is generally by augmentation. Whatever occasions the precipitation of the dissolved water seems to gain ground. As these clouds move about, they approach each other and then stretch out their ragged arms towards each other. This is not by an augmentation but by a real bending of these tatters towards the other cloud. They seldom come into contact; but, after coming very near in some parts, they as plainly recede, either in whole or by bending their arms away from each other. But, during this confused motion, the whole mass of small clouds approaches the great one above it; and when near it, the clouds of the lower mass frequently coalesce with each other before they finally coalesce with the upper cloud; but as frequently the upper cloud increases without them. Its lower surface, from being level and smooth, now becomes ragged, and its tatters stretch down towards the others, and long arms are extended towards the ground. The heavens now darken apace, the whole mass sinks down; wind arises, and frequently shifts in squalls; small clouds are now moving swiftly in various directions; lightning now darts from cloud to cloud. A spark is sometimes seen coexistent through a vast horizontal extent, of a crooked shape, and of different brilliancy in its different parts. Lightning strikes between the clouds and the earth-frequently in two places at once. A continuation of these shapes rarefies the cloud, and in time it dissipates. This is accompanied by heavy rain or hail, and then the upper part of the clouds is high and thin. During this progress of the storm the thunder rod is strongly electrified, chiefly when the principal cloud is over head. The state of the electricity frequently changes from positive to negativealmost every flash, however distant, occasions a sudden start of the electroscope, and then a change of the electricity. When the cloud is more uniform, the electricity is so too. The question now is, In what manner does the air acquire this electricity? How come its different parts to be in different states, and to retain this difference for a length of time? and how is the electric equilibrium restored? But upon these subjects we need add nothing to what is already said under ELECTRICITY. The electric equilibrium is in

deed restored with surprising rapidity and to a great extent. Yet we know that air is a very imperfect conductor, and transmits electricity to small distances only, and very slowly. But air is rendered electrical in a great variety of ways. All operations which excite electricity in other bodies have the same effect on air. It is electrified by friction. When blown on any body, such as glass, &c., that body exhibits electricity by a sensible electroscope. We therefore conclude that the air has acquired the opposite electricity from this rubber. A glass vessel, exhausted of air and broken in the dark, gives a loud crack and a very sensible flash of light. An air gun, discharged (without a ball) in the dark, does the same. Blowing on an electric with a pair of bellows never fails to excite it. In short the facts to this purpose are numberless. Most of these and other phenomena are taken notice of under ELECTRICITY. These facts are also to be found among many experiments of M. Saussure. We see some of the effects very distinctly in several phenomena of thunder and lightning. Thus the great eruptions of Etna and Vesuvius are always accompanied by forked lightnings, which are seen darting among the volumes of emitted smoke and steam. Here is a very copious conversion of water into elastic steam; and here also it is most reasonable to expect a copious decomposition of water by the iron and coaly matters, which are exposed to the joint action of fire and water. These two electricities will be opposite; or when not opposite will not be equal; in either of which cases we have vast masses of steam in states fit for flashing into each other. The simple solution of water in air produces electricity. And this is the chief operation in nature connected with the state of the atmosphere. It is thus that the watery vapors from all bodies, and particularly the copious exudation of plants, disappear in our atmosphere. There can be no doubt but that the opposite electricity will be produced by the precipitation of this vapor; that is, by the formation of clouds in clear air. Lastly, we know that the tourmalin, and many of the columnar crystals, are rendered electrical by merely heating and cooling. When water is precipitated, and forms a cloud, it is reasonable to expect that it will have the electricity of the air from which it is precipitated. This may be various, but is in general negative; for the heat by which the air was enabled to dissolve the water made it negative. But if it be cooled so fast as to precipitate it in the form of rain, or snow, or hail, we may expect positive electricity. Accordingly, in summer, hail showers always show strong positive electricity; so does snow when falling dry. Here, then, are copious sources of atmospheric electricity. The masses of air thus differently constituted are evidently disposed in strata. The clouds are seen to be so. When the wind, or stratum in motion, does not push all the quiescent air before it, it generally gets over it, and then flows along its upper side, and, by a partial mixing, produces a fleecy cloud. This is the state of the atmosphere, consisting of strata of clear air many hundred yards thick, separated from each other by thin fleeces of clouds. This is no fancy; for we ac

tually see the sky separated by strata of clouds at a great distance from each other. And we see that these strata maintain their situations, without farther admixture, for a long time, the bounding clouds continuing all the while to move in different directions. In 1783, when a great fleet rendezvoused in Leith Roads, the ships were detained by an easterly wind which had blown for six weeks without intermission. The sky was generally clear; sometimes there was a thin fleece of clouds at a great height, moving much more slowly in the same direction with the wind below. During the last eight days the upper current was from the westward, as appeared by the motion of the upper clouds. High towering clouds came down the river with a little rain; the strata were jumbled, and the whole atmosphere grew hazy and uniform; then came thunder and heavy rain, and the wind below shifted to the west. Thus it is sufficiently evinced that the atmosphere frequently consists of such strata well distinguished from each other; their appearance and progress leave us no room to doubt but that they come from different quarters, and had been taken up or formed at different places, and in different circumstances, and therefore differing in respect of their electrical states. The consequence of their continuing long together would be a gradual but slow progress of their electricity to a state of equilibrium. The air is perhaps never in a perfectly dry state, and its moisture will cause the electricity to diffuse itself gradually. But thunder requires a rapid communication, and a restoration of electric equilibrium in an instant and to a vast extent. The means for this are at hand. The strata of charged air are furnished with a coating of cloud. The lower stratum is coated on the under side by the earth. When a jumble is made in any of the strata, a precipitation of vapor must generally follow. Thus a conductor is brought between the electrical coatings. This will quickly enlarge. In this manner the interposed cloud immediately attracts other clouds, grows ragged by the passage of electricity through clear air, where it causes a precipitation by altering the natural equilibrium of its electricity. Accordingly we see in a thunder storm that small clouds continually and suddenly form in parts formerly clear. Whatever causes thunder, does in fact promote this precipitation. These clouds have the electricity of the surrounding air, and must communicate it to others in an opposite state and within reach. They must approach them, and must afterwards recede from them, or from any that are in the same state of electricity with themselves. Hence their ragged forms, and the similar form of the under surface of the great cloud; hence their continual and capricious shifting from place to place; they are carriers which give and take between the other clouds, and they may become stepping stones for the general discharge. If a small cloud form a communication with the ground, and the great cloud be positive or negative, we must have a complete discharge, and all the electrical phenomena, with great violence; for this coating of vapor is abundantly complete for the purpose. The general scene of thunder is the heavens; and it

is by no means a frequent case that a discharge is made into the earth. The air intervening between the earth and the lowest coating is commonly very much confused in consequence of the hills and dales, which, by altering the currents of the winds, toss up the inferior parts and mix them with those above. This generally keeps the earth pretty much in the same electrical state as the lowest stratum of clouds. There are, however, many melancholy instances of the violent effects of thunder storms on the earth.

THUNDERBOLT. When lightning acts with extraordinary violence, and breaks or shatters any thing, it is called a thunderbolt, which the vulgar, to fit it for such effects, suppose to be a hard body, and even a stone. When we consider the known effects of electrical explosions, and those produced by lightning, we shall be at no loss to account for the extraordinary operations vulgarly ascribed to thunderbolts. As stones and bricks, struck by lightning, are often found in a vitrified state, we may reasonably suppose, with Beccaria, that some stones in the earth having been struck in this manner gave occasion to the vulgar opinion of the thunderbolt.

THUNDERSTORM, a storm of lightning and thunder, generally attended with hail, rain, and wind.

THURGOVIA, or THURGAU, a canton in the north-east of Switzerland, adjoining the lake of Constance and the course of the Thur. Its extent is 350 square miles. The surface is in part level, and the hills, where they occur, do not exceed a height of 2500 feet above the lake. The products are wheat, barley, oats, rye, flax, hemp, and vines, and the pastures are extensive. Apple trees abound; occupying in various places orchards, and in one quarter an extensive forest. Cotton and silk are both manufactured; but the staple article is linen, which was introduced so far back as the thirteenth century. The canton is divided into eight bailiwics. Population 77,000, of whom one-fourth only are Catholics, the others Calvinists.

THURIA, an ancient town of the Morea, in Messenia, towards the eastern frontier, the ruins of which are still extensive, covering a hill at the foot of the ridge of Taygetus.

THURIE, THURII, or THURIUM, an ancient town of Italy, in Lucania, built by a colony of Athenians near the ruins of Sybaris, A. A. C. 444. Among these colonists were Herodotus the historian and Lysias. Strab. vi. Mela ii. 4.

THURIA, a town of Messenia.-Paus. THURIFICATION, n. s. Lat. thuris and facio. The act of fuming with incense; the act of burning incense.

The several acts of worship which were required to be performed to images are processions, genuflections, thurifications, deosculations, and oblations.

Stillingfleet.

THURINGI, the ancient inhabitants of Thuringia. They were a tribe of the Catti, or, according to others, of the Vandals. They are mentioned by Tacitus, and were very numerous. THURINGIA, in ancient geography, the country of the ancient Thuringi, was formerly a kingdom, afterwards a county, then a landgravate, and was governed by its own princes for

many ages till 1124, when it devolved to the marquis of Misnia, and, with that country, afterwards to the duke of Saxony.

THURINGIA FOREST, a hilly and woody tract of country in the interior of Germany, extending through a number of petty principalities, Eisenach, Gotha, Weimar, Coburg, &c. It is a part of the ancient Hercynian forest, has a length of about seventy miles, and varies in breadth from nine to sixteen, covering an area of about 1000 square miles. It is thinly peopled, containing only hamlets or small villages. It is, however, rich in metals, particularly iron. Its highest peaks vary in height from 2000 to 2800 feet. It is covered with wood in every direction, and gives rise to a number of streams which flow into the adjacent plain, and finally into the Maine, the Weser, and the Elbe.

THURLOE (John), an English statesman under Oliver Cromwell, was born at Abbot's Roding in Essex in 1616, of which parish his father was rector, and was educated to the study of the law. In 1648 he was made receiver of the cursitory fines. When Oliver Cromwell assumed the protectorship he became secretary of state; in 1655 he had the care and charge both of foreign and inland postage; and was afterwards sworn a member of the privy-council. He was continued in the same offices under Richard Cromwell, and until measures were taken for the restoration, when he made an offer of his services to that end, which, however, was not accepted. May 15th, 1660, he was committed to the custody of the serjeant at arms on a charge of high treason; but being soon released he retired to Great Milton in Oxfordshire; and, though he was afterwards often solicited by Charles II. to engage in the administration of public business, he declined the offers. He died in 1668; and was a man of an amiable private character, who in the highest of his power exercised all possible moderation towards persons of every party. The most authentic testimony of his abilities is his vast collection of state papers, in 7 vols. folio.

THURLOW (Edward), lord high chancellor of Great Britain, was born in 1758, at Ashfield, Norfolk, and, after passing some time at Cambridge, came to London to study the law. He was called to the bar in 1758, and raised himself to notice by his manly opposition to Sir Fletcher Norton. In the Douglas cause he displayed such ability that the public attention was turned towards him as formed to reach the highest stations in his profession. In 1770 he was appointed solicitor general, and the next year attorney general. In June 1778 he was created a chancellor. This office he resigned in 1783, but, peer, and the day following nominated lord high on the re-admission of Mr. Pitt into the cabinet, he again was promoted to the seals, and kept them till 1793. After that time he lived in retirement, and died, after an illness of two days, at Brighthelmstone, 12th September, 1806. His character as a lawyer is fixed on the firm basis of his extensive knowledge, quick penetration, correct judgment, and undeviating integrity. Though overbearing in his manners, he was zealously attached to his party, inflexible in his opinions, and loyal in his conduct

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