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 CLOTILDE DE SURVILLE CLOUDS 709 in the hands of her sons Ohildebert and Clo- taire. She spent the latter part of her life in Tours, near the tomb of St. Martin, became noted for her piety, founded several monas- teries and churches which acquired great celeb- rity, and was canonized by the church of Rome. According to her desire, she was buried in the church of Ste. Genevidve, Paris, built by Clovis. Saved from destruction during the revolution, her remains are now in the church of St. Leu, and a new church has been built in her honor. Her marble statue is in the Luxembourg. See Vie de Sainte Clotilde, by Mrae. de Kenneval (2 vols., Paris, 1809). II. A daughter of the preceding, died in 531. Her husband, Amalaric, king of the Visigoths, ill-treated her, and she was insulted by the populace because she declined to become a convert to Arianism. Her brother Childebert, on receiving her veil stained with the blood of a wound inflicted upon her by her husband, invaded Amalaric's territory, despoiled the churches of Narbonne, and took her with him to Paris ; but she died on the way. CLOTILDE DE SURVILLE. See SUEVILLE. CLOUD, a N". county of Kansas, intersected by Republican and Solomon rivers ; area, 720 sq. m. ; pop. in 1870, 2,323. The chief pro- ductions in 1870 were 21,794 bushels of wheat, 76,105 of Indian corn, 4,735 of oats, 11,609 of potatoes, 3,224 tons of hay, and 25,871 Ibs. of butter. There were 894 horses, 842 milch cows, 2,123 other cattle, 614 sheep, and 637 swine. Capital, Concordia. CLOUDS, bodies of vapor in the atmosphere. From the surface of the earth and of the waters aqueous vapor is continually ascend- ing into the atmosphere, where it remains in an invisible state so long as the air is not satu- rated with moisture. Its capacity to retain this vapor is limited, but varies with its tem- perature ; the greater the warmth, the more the particles of vapor are expanded and carried into higher regions. Cold condenses the par- ticles, their specific gravity is increased, and they appear in visible form. (See DEW.) Satu- rated to the utmost, the atmosphere cannot contain, it is estimated, more than 6 to 7 inches of water, diffused through it in an invisible state, at one time. But the diffusion of vapor is never uniform, and the temperature also varying in different portions of the atmos- phere, there ensues the greatest diversity in the conditions of the moisture contained in these portions. Where it is not too abundant for the existing temperature, it is all dissolved, and the appearance is presented of the clear, blue, invisible ether. Where the moisture is in excess for the temperature, it is seen in the form of clouds, thin and fleecy if the air is but slightly sursaturated, but dark and lowering if new accessions of moisture or reduction of temperature increase the difference between the moisture present and the capacity of the air to retain it. Thus the conditions are seen that cause frequent changes in the appearance of the clouds ; and it is understood how clouds filled with moisture, like those gathered by the Etesian winds as they sweep over the Mediter- ranean, are dispersed in thin air as they strike the hot rays reflected from the burning sands of Sahara; and how those similarly charged with moisture by the sweeping of the trade winds across the Atlantic shed this in copious showers as they strike the cold summits of the Cordilleras. The -formation of a cloud by cold and its dispersion by heat are beautifully ex- hibited at the Table mountain, Cape of Good Hope. As the wind from the southern ocean strikes the rocky slopes of the mountain and is diverted upward into the colder regions of the atmosphere, a dense white cloud is evolved, which, reaching but little above the mountain, spreads over its summit and is carried down the other side. It marks the course of the wind, " plunging down with the violence of a cataract," as described by Sir John F. W. Her- schel, " clinging close to the mural precipices that form a kind of background to Cape Town, which it fills with dust and uproar." But as it reaches the warmer regions below, the mois- ture soon resumes its invisible state, and the cloud is only seen covering the mountain and hanging down its precipitous sides, suggesting the idea of a huge white cloth, whence its name of "table cloth." There is much differ- ence in the height of clouds. The mean height in winter may be stated as from 4,000 to 4,600 ft., and in summer from 10,000 to 14,000 ft. ; but they often have greater altitudes. Gay- Lussac, when in a balloon at a height of 23,000 ft., observed cirrus clouds at a considerable distance above him. In Ethiopia M. d'Abadie saw storm clouds at a height of only 700 ft. above the earth. Dalton asserts that in small fleecy patches they have been seen at full five miles above the surface, sailing even over the highest summits of the Andes. But in cold regions the vapors are soon checked in their ascent by condensation. Wherever arrested, if the weather be calm, they settle down by their gfeater relative gravity, undergoing with change of position changes of form and ap- pearance, until they may be at last brought to the warmer airs below, and in these dissolving and disappearing, be again lifted into the cold- er strata to reassume the form of a cloud. Clouds are thus no permanent collections of the same particles of aqueous vapor, but spaces in the firmament in which successive portions of vapor in the atmosphere are continually pre- sented in visible form, to disappear and be re- placed by other portions. To account for the suspension of clouds various theories have been proposed. De Saussure considered the particles of vapor to be minute hollow vesicles filled with air, from ^Vir to imnr f an mcn m diameter, and he has been supported by Halley, Kratzen- stein, and Brevais. One reason offered in favor of the vesicular theory is the fact that rainbows are not produced when the sun shines on clouds or steam, as it was thought they would if the