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The effects of thunder-storms, and the vast quantity of electricity collected in the clouds which produce these storms, are so well known, that it is superfluous to mention them. It appears, however, that even these clouds are not so highly electrified as to produce their fatal effects on those who are immersed in them. It is only the discharge of part of their electricity upon such bodies as are either not electrified at all, or not so highly electrified as the cloud that produces the mischief. Professor Saussure, and young Mr. Jalabert, when travelling over one of the high Alps, supply a singular instance of being caught among clouds of this kind; to their astonishment they found their bodies so full of electrical fire, that spontaneous flashes darted from their fingers with a crackling noise, and they had the same kind of sensation as when strongly electrified by art.

The height of clouds in general is not great; the summits of very high mountains being commonly quite free from them. But those which are most electrified descend lowest, their height being often not above 700 or 800 yards above the ground; nay, sometimes thunder clouds appear actually to touch the ground with one of their edges. But the generality of clouds are suspended at the height of a mile, or little more, above the earth. Some, however, have imagined them to arise to a most incredible and extravagant beight.

The motions of the clouds are not always directed by the wind; they seem to move very slowly when we have considerable gales, and often to be absolutely stationary for a time. The reason of this probably is, that they are impelled by opposite streams of air of equal strength; by which means their velocity is retarded. In such cases both the aerial currents seem to ascend to a very considerable height; for Messrs. Charles and Roberts, when endeavouring to avoid a thunder cloud in one of their aerial voyages, could find no alteration in the course of the current, though they ascended to the height of 4000 feet from the surface of the earth. In some cases the motions of the clouds evidently depend on their electricity, independent of any current of air. Professor Leslie, in his very able article on Meteorology, in the Supplement to the Encyclopædia Britannica, contends that Dr. James Hutton first suggested the true theory of clouds, in his paper upon the subject of Rain, in the Transactions of the Edinburgh Royal Society, 1787. He thus endeavours to define and complete it :Air, in cooling, becomes ready to part with its moisture. But how is it cooled in the free atmosphere, unless by the contact or commixture of a colder portion of the same fluid? Now, the portion of the air which is chilled, must in an etual degree warm the other. If, in consequence of this mutual change of condition, the former be disposed to resign its moisture, the latter is more inclined to retain it; and, consequently, if such opposite effects were balanced, there could, on the whole, be no precipitation of humidity whatever. The separation of moisture, on the mixing of two masses of damp air at different temperatures, would therefore prove, that the dissolving power of air suffers more diminution from losing

part of the combined heat, than it acquires augmentation from gaining equal measure of it; and, consequently, this power must, under equal accessions of heat, increase more slowly at first than it does afterwards, thus advancing always with accumulated celerity.

'The quantity of moisture which air can hold thus increases in a much faster ratio than its temperature. This great principle in the economy of nature was traced by Dr. Hutton from indirect experience. It is the simplest of the accelerating kind, and perfectly agrees with the law of solution, which the hygrometer has established. Suppose equal bulks of air in a state of saturation, and at the different temperatures of 15 and 45 centesimal degrees, were intermixed, the compound arising from such union will evidently have the mean temperature of 30°. But since, at these temperatures, the one portion held 200 parts of humidity, and the other 800, the aggregate must contain 1000 parts, or either half of it 500; at the mean or resulting temperature, however, this portion could only suspend 400 parts of humidity, and consequently, the difference, or 100 parts, amounting to the 200dth part of the whole weight of air, must be precipitated from the compound mass. As another illustration, let air of 15° be mixed with air at the temperature of 35°, in three different proportions, all at the point of saturation; one part being combined with three parts, two with two, and three with one. The temperatures arising from the commixture would be 20°, 25°, and 30°; the corresponding parts of moisture precipitated from the mass being derived from the intermediate proportions of 200 and 504, are 352-317-5, or 34-5, 276-252 or 24, 352-317-5 or 34.5, and 428—400 or 28.

'In these examples we have assumed the portions of differently heated air to be quite charged with moisture before mixing; but it is only required that they should approach to the point of humidity. The effect, however, of simple commixture would, in most cases, be very small. To explain the actual phenomena, we must have recourse to the mutual operation of a chill and of a warm current, driving swiftly in opposite directions, and continually mixing and changing their conterminous surfaces. By this rapidity, a larger volume of the fluid is brought into contact in a given time. Suppose, for instance, the one current to have a temperature of 50°, and the other that of 70°, by Fahrenheit's scale; the blending surfaces will therefore assume the mean temperature of 60°. Consequently, the two streams throw together 200 and 234-2 parts of moisture, making 567-1 parts for the compound, which, at its actual temperature, can hold only 2586 parts; the difference, or 8.6 parts, forms the measure of precipitation, corresponding to the 2325th of the whole weight of the commixed air. It would thus require a column of air thirty miles in length to furnish, over a given spot, and in the space of an hour, a deposit of moisture equal to the height of an inch. If the sum of the opposite velocities amounted to sixty miles an hour, and the intermingling influence extended but to a quarter of an inch at the grazing surfaces, there would still, on this supposition,

be produced in the same time a fall of rain reaching to half an inch in altitude.

These quantities come within the limits of probability, and agree sufficiently with experience and observation. But in the higher temperatures, though the difference of the heat between the opposite strata of air should remain the same, the measure of aqueous precipitation is greatly increased. Thus, while the mixing of equal masses of air, at the temperatures of 40° and 602, is only 6.6, that from a like mixture at 80° and 100° amounts to 190. This result is entirely conformable to observation; for showers are most copious during hot weather, and in the tropical climates. The quantity of moisture precipitated from the atmosphere thus depends on a variety of circumstances on the, previous dampness of the commixed portions of the fluid; their difference of heat; the elevation of their mean temperature; and the extent of the combination which takes place. When this deposition is slow, the very minute aqueous globules remain suspended, and form clouds; but if it be rapid and copious, those particles conglomerate, and produce, according to the state of the medium with regard to heat, rain, hail, or snow.'

But Mr. Luke Howard of London has furnished the most complete classification and exposition of these phenomena, in his Nomenclature and Observations on Clouds, published in the 16th and 17th vols. Philosophical Magazine.

The simple modifications are thus defined: 1. Cirrus. Parallel, flexuous, or diverging fibres, extensible in any or in all directions. 2. Cumulus. Convex or conical heaps, increasing upwards from a horizontal base. 3. Stratus. A widely extended, continuous, horizontal sheet, increasing from below.

The intermediate modifications which require to be noticed are, 4. Cirro-cumulus. Small welldefined roundish masses, in close horizontal arrangement. 5. Cirro-stratus. Horizontal, or slightly inclined masses, attenuated towards a part or the whole of their circumference, bent downward or undulated, separate or in groups, consisting of small clouds having these characters.

The compound modifications are, 6. Cumulostratus. The cirro-stratus, blended with the cumulus, and either appearing intermixed with the heaps of the latter, or superadding a widespread structure to its base.

7. Cumulo-cirro-stratus, vel nimbus, is the rain cloud. A cloud or system of clouds from which rain is falling. It is a horizontal sheet, above which the cirrus spreads, while the cumulus enters it laterally and from beneath.

The cirrus appears, according to this author, to have the least density, the greatest elevation, the greatest variety of extent and direction, and to appear earliest in serene weather, being indicated by a few threads pencilled on the sky. Before storms they appear lower and denser, and usually in the quarter opposite to that from which the storm arises. Steady high winds are also preceded and attended by cirrus streaks, running quite across the sky in the direction they blow

in.

The cumulus has the densest structure, is formed in the lower atmosphere, and moves

along with the current next the earth. A smasl irregular spot first appears, and is, as it were, the nucleus on which they increase. The lower surface continues irregularly plane, while the upper rises into conical or hemispherical heaps; which may afterwards continue long nearly of the same bulk, or rapidly rise into mountains. They will begin, in fair weather, to form some hours after sunrise, arrive at their maximum in the hottest part of the afternoon, then go on diminishing and totally disperse about sunset. Previous to rain, the cumulus increases rapidly, appears lower in the atmosphere, and with its surface full of loose fleeces or protuberances. The formation of large cumuli to leeward in a strong wind, indicates the approach of a calm with rain. When they do not disappear or subside about sunset, but continue to rise, thunder is to be expected in the night. The stratus has a mean degree of density, and is the lowest of clouds, its inferior surface commonly resting on the earth or water. This is properly the cloud of night appearing about sunset. prehends all those creeping mists, which in calm weather ascend in spreading sheets, like an inundation of water, from the bottom of valleys, and the surfaces of lakes and rivers. On the return of the sun, the level surface of this cloud begins to put on the appearance of cumulus, the whole at the same time separating from the ground. The continuity is next destroyed, and the cloud ascends, and evaporates, or passes off with the appearance of the nascent cumulus. This has long been experienced as a prognostic of fair weather.

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The cirrus having continued for some time increasing or stationary, usually passes either to the cirro-cumulus or the cirro-stratus, at the same time descending to a lower station in the atmosphere. This modification forms a very beautiful sky; is frequent in summer, an attendant on warm and dry weather. The cirro-stratus, when seen in the distance, frequently gives the idea of shoals of fish. It precedes wind and rain; is seen in the intervals of storms; and sometimes alternates with the cirro-cumulus in the same cloud, when the different evolutions form a curious spectacle. A judgment may be formed of the weather likely to ensue by observing which modification prevails at last. The solar and lunar haloes, as well as the parhelion and paraselene (mock sun and mock moon), prognostics of foul weather, are occasioned by this cloud. The cumulo-stratus precedes, and the nimbus accompanies rain. Mr. Howard gives a view of the origin of clouds, which will be found worth consulting. The uses of the clouds are obvious; from them proceeds the rain which refreshes the earth, without which according to the present system of nature, the whole of its surface would be a mere desert. They are likewise of great use as a screen, interposed between the earth and the scorching rays of the sun, which are often so powerful as to destroy the grass and other tender vegetables. In the more secret operations of nature also, where the electrical fluid is concerned, the clouds bear a principal share; and serve as a medium for conveying that fluid from the atmosphere into the earth, and from the earth into the atmosphere.

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L'irrus or Curlcloud-2.Cirrocumulus or Sonderclond-3.4.5.Cirrostratus or Wanecloud-6. Cumulostratus er Twainloud-7. Cummhus r Stakencloud-8.Nimbus Rainclond-9. Stratum or Falleloud.

London Lubushed by Thomas lega. 73.theupside. May.11827.

J.Shury. Se.

CLOUD (St.), a town and palace of France, in the province of the Isle of France, situated on the Siene. The palace, though not the largest, is one of the most pleasantly situated, and beautiful, of any in the neighbourhood of Paris. It contains several beautiful specimens of the fine arts, has a park, gardens, and cascades. The great cascade is 108 feet in width, and the same in height. The terrace affords an extensive view of Paris. Henry III. was assassinated here in 1580, and here Napoleon principally resided. It has a fine manufacture of porcelain; five miles west of Paris.

CLOUDBERRY, n. s. from cloud and berry, chamamorus. The name of a plant, called also knotberry.

CLOUDCAPT, adj. from cloud and cap. Topped with clouds,; touching the clouds.

The cloudcapt towers, the gorgeous palaces,
The solemn temples, the great globe itself,
Yea, all which it inherits, shall dissolve. Shakspeare.
CLOUDCOMPELLING, adj. A word form-
ed in imitation of vegeλnyéperns, ill understood.
An epithet of Jupiter, by whom clouds were sup-
posed to be collected.

Health to both kings, attended with a roar
Of cannons, echo'd from the affrighted shore;
With loud resemblance of his thunder prove
Bacchus the seed of cloudcompelling Jove.

Supplicating move

Waller.

Dryden.

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And for his aspect, look upon the fountain,
And then on me, and judge which of us twain
Look likest what the boors believe to be
Their cloven-footed terror.

Byron. Deformed Transformed.
Dutch kliver; Sax.

CLOVER, n. s.
CLOVER-GRASS, n. s. clafer; from its cleft
CLOVERED, adj. leaves, a species of tre-
foil; a rich provision for cattle; and so great a
luxury, that when an individual has all the
comforts of life in abundance, he is said to live

in clover.

The freckled cowslip, burnet, and green clover.

The even mead, that erst brought sweetly forth

Nature shall provide

Shakspeare.

Green grass and fattening clover for their fare.

Dryden.
Clover improves land, by the great quantity of cattle
it maintains.
Mortimer's Husbandry.
My Blouzelinda is the blithest lass,
Than primrose sweeter, or the clover grass.
Flocks thick nibbling thro' the clovered vale.

Gay.

Thomson.
Well, Laureat, was the night in clover spent. Ogle.
CLOVER, in botany. See TRIFOLIUM, and
AGRICULTURE.

Thy just complaint to cloudcompelling Jove.
CLOVE, n. s. the preterite of cleave. See To hill; a vale between cliffs.
CLEAVE.

CLOUGH, n. s. Sax. clough. The cleft of a

Gyon's angry blade so fierce did play
On the other's helmet, which as Titan shone,
That quite it clove his plumed crest in tway.

Faerie Queene.

CLOVE, n. s. Fr. clou, a nail, from the similitude of a clove to a nail. A valuable spice brought from Ternate in the East Indies. It is the fruit or seed of a very large tree.

Clove seems to ue the rudiment or beginning of a fruit growing upon clove-trees.

Browne's Vulgar Errours. Some of the parts into which garlick separates, when the outer skin is torn off. In this sense it is derived from clove, the preterite of cleave. Tis mortal sin an onion to devour; Each clove of garlick is a sacred power.

Tate's Juvenal

CLOVE JULY-FLOWER. See DIANTHUS.
CLOVE-TREE. See CARYOPHYLLUS.

CLOUGH, n. s. in commerce, an allowance of two pounds in every hundred weight for the turn of the scale, that the commodity may hold out weight when sold by retail.

CLOVIO (George Julius), a celebrated histoin 1498. At eighteen years of age he went to rical and portrait painter, was born at Sclavonia Rome, where he spent three years, devoting himself entirely to painting in miniature. His knowledge of coloring was established by the instructions of Julius Romano, and his taste of composition and design was founded on the works of Michael Angelo. He thus acquired so great a degree of excellence in portrait, as well as in historical painting, that in the former he was considered equal to Titian, and in the latter not inferior to Buonaroti. He died in 1578. His works are exceedingly valuable, and are still numbered among the curiosities of Rome.

CLOVIS I, the real founder of the French monarchy, was born in 467, and succeeded his

CLOVEN, part. pret. from cleave. See To father Childeric in 481. His first exploit was

CLEAVE.

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the defeat of Syagrius, the Roman governor of Gaul, after which he took Soissons, and made it his capital. His wife Clotilda prepared him for the reception of Christianity, which, however, he did not embrace till after a victory obtained over the Germans, which he attributed to the effect of his prayer to the God of the Christians before the battle. He was soon after publicly baptised with 3000 of his subjects, by St. Reni, archbishop of Rheims, and his fitness for the ceremony may be judged of from his declaration on hearing of the sufferings of Christ. 'Had I been there,' said he, with my valiant Goths, how I would have avenged him!' He was a warlike prince, and conquered the several provinces of

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