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land. At an interview between Tyler and the king, in Smithfield, the former was murdered by some of the attendants of the latter, under pretence that the rebel leader seemed about to seize the king's bridle. The revolt was extinguished with circumstances of great cruelty; more than 1500 wretches perishing by the hand of the hangman. These commotions were not confined to England; and they indicate the growing light of knowledge, which rendered the people impatient of personal slavery, then general (see Villenage), and of the chains which a haughty nobility had imposed upon them. Their concur rence with the attempts towards religious reform (see Wickliffe) must not be overlooked. "A foolish priest of Kent," says Froissart, "had preached to the peasants that, in the beginning of the world, there were no bondmen. 'Why,' said he, 'should they be kept under, like wild beasts? and why, if they labored, should they have no wages?

When Adam delved, and Eve span, Where was then the gentleman ?' "'. "Two verses," says Hume, "which, in spite of prejudice, one cannot but regard with some degree of approbation."

WATCH AND CLOCK MAKING. A clock or a watch movement is an assemblage of wheels and pinions, contained in a frame of two brass plates, connected by means of pillars, the first or great wheel of which, in an eight day clock movement, has concentric with it a cylindrical barrel, having a spiral groove cut on it. To this cylinder is attached one end of a cord, which is wrapped round in the groove, for any determined number of turns; and to the other end of the cord is hung a weight, which constitutes a power or force to set the wheels in motion. Their time of continuing in motion will depend on the height through which the weight has to descend, on the number of teeth in the first or great wheel, and on the number of teeth or leaves of the pinion upon which this wheel acts, &c. The wheels in spring clocks, and in watches, are urged on by the force of a spiral spring, contained in a hollow cylindrical barrel, or box, to which one end of a cord or chain is fixed, and lapping it round the barrel for several turns outside: the other end is fixed to the bottom of a solid, shaped like the frustrum of a cone, known by the name of the fusee, having a spiral groove cut on it on the bottom of this cone, or fusee, the first or great wheel is put. The arbor, on which the spring barrel turns, is so fixed in the frame, that it cannot turn

when the fusee is winding up: the inner end of the spring hooks on to the barrel arbor, and the outer end hooks to the inside of the barrel. Now, if the fusee is turned round in the proper direction, it will take on the cord or chain, and, consequently, take it off from the barrel. This bends up the spring; and, if the fusee and great wheel are left to themselves, the force exerted by the spring in the barrel to unbend itself, will make the barrel turn in a contrary direction to that by which it was bent up. This force of the spring unbending itself, being communicated to the wheels, will set them in motion, and they will move with considerable velocity. Their time of continuing in motion will depend on the number of turns of the spiral groove on the fusee, the number of teeth in the first or great wheel, and on the number of leaves in the pinion upon which the great wheel acts, &c. The wheels, in any sort of movement, when at liberty, or free to turn, and when impelled by a force, whether it is that of a weight or of a spring, would soon allow this force to terminate; for, as the action of the force is constant from its first commencement, the wheels would be greatly accelerated in their course, and it would be an improper machine to register time or its parts. The necessity of checking this acceleration, and making the wheels move with a uniform motion, gave rise to the invention of the escapement, or 'scapement, as it is commonly called. To effect this, an alternate motion was necessary, which required no small effort of human ingenuity to produce. The escapement is that part of a clock or watch connected with the beats which we hear it give; and these beats are the effects of the moving power, carried forward by means of the wheels in the movement to the last one, which is called the swing wheel in a pendulum clock, and the balance wheel in a watch. The teeth of this wheel act on the pallets or verge, which are of various shapes, and which form the most essential part in a 'scapement; they drop from each tooth of the swing or balance wheels, on their respective pallets, giving one beat or impulse to the pendulum or balance, in order to keep up or maintain their motion; and, were it not for the pallets, which alternately stop the teeth of the swing or balance wheels, the motive force would have no check. Hence it is that, by this mechanism of the 'scapement the wheels in the movement are prevent ed from having their revolutions accelerated, which would take place to such a

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degree as to make the machine run down in a minute or two; whereas, from the resistance opposed by the pallets, it is kept going for twenty-four or thirty hours, for a week or a month, or even for twelve months. In the clocks or watches, however, which, as a matter of curiosity, have been made to go so long, it was not possible to have an accurate measure of time. (For the historical matter connected with this subject, see Clock.)

WATELET, Claude Henry; a French writer of eminence on the fine arts and the belles-lettres. He held the office of a receiver-general of the finances, was a member of the French academy, and of several foreign learned societies, and died at Paris, in 1786, aged sixty-eight. He published, in 1760, a poem Sur l'Art de peindre, and was the author of several other works, the most important of which is the Dictionary of Painting, Sculpture and Engraving, forming part of the Encyclopédie Méthodique.

WATER. The composition of this fluid has been fully demonstrated both from analysis and synthesis. It is found that when hydrogen gas is burnt (an operation in which oxygen is combined with it), water is formed, and is the only sensible product. This is the proof by synthesis. On the other hand, when water is acted on by substances capable of attracting oxygen, these are oxidated, the water disappears, and hydrogen gas is evolved. The proportions of these elements in water are as follows: one volume of oxygen to two volumes of hydrogen; or, by weight, eight parts oxygen to one of hydrogen. Water is a transparent and colorless liquid, destitute of smell, and nearly without taste. It refracts light powerfully. When its internal movements are prevented, it is a very slow conductor of heat, and an imperfect conductor of electricity. It is almost incompressible, a pressure equal to 2000 atmospheres occasioning a diminution of only one ninth of its bulk. Water being the substance most easily procured in every part of the earth in a state of purity, it has been chosen, by universal consent, to represent the unit of the specific gravity of all solid and liquid bodies. When we say the specific gravity of a body is two, we mean that it weighs twice as much as the same volume of water would do. Now, a cubic foot of water, at the temperature of 60° Fahr., and when the barometer stands at 30 inches, weighs 998.217 avoirdupois ounces, which is only 1.783 ounces less than 1000. Hence, if we know the specific gravity of a body, 8

VOL. XIII.

we have very nearly the weight of a cubic foot of it in avoirdupois ounces. 100 cubic inches of air at 60° Fahr., when the barometer stands at 30 inches, weigh 31.1446 grains. Hence it follows that water, at that temperature and pressure, is 810.734 times heavier than air. Water passes to the solid state at 32° Fabr. When it shoots into ice, it forms, in the first place, a prism, not very regular in shape, but very long. From this primary prism other smaller ones shoot out on both sides, and always at angles of 60° and 120°. Hail is always crystallized in the form of two six-sided pyramids applied base to base. Ice has been observed in crystals having the form of a rhomboid of 120° and 60°. In taking the solid form, water undergoes an enlargement of volume from eight parts to nine; and this expansion even takes place previous to the congelation, during the reduction of temperature for six or eight degrees, the greatest density of water being about 40° Fahr. In the act of freezing, too, the greater part of the air, which the water holds loosely dissolved, is expelled. Electricity is also rendered sensible in its congelation. Water passes into vapor when exposed to the atmosphere at any natural temperature, and even ice evaporates, as is proved by its losing weight when suspended in the air. The transition into vapor is promoted by heat: at 212°, under a medium atmospheric pressure, water boils. (See Steam.) Water absorbs the aerial fluids, but in quantities very different, according to the force of attraction which it exerts towards them. Of some of the acid gases it absorbs many times its own volume; of others, the quantity is so inconsiderable as not to be very perceptible, unless ascertained by an apparatus peculiarly adapted to show the result. The quantities absorbed are greater as temperature is low, down to freezing. They are also augmented by pressure. 100 cubic inches of recently-boiled water, at the mean temperature and pressure, absorb of

100

the

Carbonic acid,
Sulphureted hydrogen, 100 cubic inches.
Nitrous oxide,
Olefiant gas,.
Oxygen,

Carbonic oxide, Nitrogen,. Hydrogen,

66

100 '. 12.5

66

66

66

3.7 1.56 66 1.56 1.56 66

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A water which has been exposed to he atmosphere (as spring and river water) contains a portion of air, from which t

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derives a sparkling quality and agreeable taste. It is thus also fitted for supporting the respiration of fishes It appears that the oxygen is absorbed in preference to the nitrogen, and in considerably larger quantity. All the powerful acids exert a strong attraction for water, such as the sulphuric, the nitric, muriatic, fluoric and phosphoric acids. Few of these can even be obtained free from it in an insulated state; and it appears to have an important effect in their more characteristic acid properties. A strong attraction is exerted between water and the fixed alkalies, as also between it and the alkaline earths. The compound salts, also, always contain water, even those of them which appear altogether insoluble. Water, though incapable of combining with the metals, exerts a chemical action upon them, affording to several of them oxygen, at the temperature of ignition, and, at a natural emperature, aided by atmospheric air, xidating or corroding others: it also comoines with some of their oxides. Water is a solvent of many other substances. Few of the animal or vegetable products are insoluble in it, and all of them are affected by it as a chemical agent. Those compounds in which water exists in intimate combination, and the properties of which it appears to modify, are named hydrates. It sometimes exists in union, in the proportion of one atom (represented by nine to hydrogen as one); sometimes two atoms (or eighteen parts by weight) are combined, and sometimes even ten atoms. From the extensive solvent power of water, it is scarcely ever met with pure in nature. Every kind of spring or river water is impregnated with saline and earthy bodies of different kinds. Spring water contains carbonate of lime, muriate of lime, and muriate of soda, with a trace of magnesia, and often a little sulphate of potash or soda. River water contains carbonate of lime, muriate of soda, and each of these also sometimes a little alkali. Well water, besides these, contains always a portion of sulphate of lime, the presence of which is the chief cause of the quality termed hardness in waters. Rain or snow water is freer from these foreign substances, but is not perfectly pure, as it affords a trace of muriate of soda and muriate of lime. The presence of these different saline and earthy substances is judged of by the following tests, added in the quantity of a few drops of each to an ounce or two of water. A solution of nitrate of barytes produces a

turbid appearance from the presence of any sulphate or carbonate, and the turbid appearance of it arising from the latter is removed on adding a drop or two of pure nitric acid. A solution of nitrate of silver gives a bluish precipitate from the presence of any muriate; and if this test is applied after the previous application of nitrate of barytes (care being taken that this last is free from all muriatic acid), it is more certain, as any precipitation from the presence of a sulphate or carbonate is removed. A solution of acetate of lead causes a turbid appearance, if sulphates or carbonates are present; while it produces a less marked effect from the presence of muriates. A solution of oxalate of ammonia detects lime by precipitation; and a solution of soap in alcohol indicates, by the degree of turbid appearance it produces, the predominance of sulphate of lime, or the degree of hardness, as it is called. If a solution of phosphate of soda produce a milkiness after a previous addition of a similar quantity of carbonate of ammonia, magnesia is present. The presence of free carbonic acid is detected by a slight milkiness being produced by the addition of an equal portion of lime water to the water, and with still more delicacy by super-acetate of lead. It is also discovered in the air expelled by boiling, which, on being agitated with lime water, affords a milky precipitate. Water is freed from all foreign substances by distillation.

WATERS, MINERAL. Under the article Mineral Waters, in this work, their definition was given, and a division of them into classes pointed out: a notice also of some of their principal localities was appended. In this place, we shall present some additional information respecting the localities of mineral waters (particulary American), their temperature, chemical constitution, and medicinal qualities. The division of mineral waters above alluded to, was into sulphureous, carbonated, chalybeate and saline. Among the most celebrated waters of the sulphureous class are those of Aix-la-Chapelle, twelve leagues west from Cologne, nine northeast from Liege, and eighty from Paris. Its thermal waters appear to have been known to the Romans; but they owe their modern fame to Charlemagne, who made Aix-la-Chapelle his residence, and occasionally held his levee in the bath,with all his attendants. The temperature of these waters varies, at the different baths, from 110° to 143° Fahr. They contain car

Nitrogen,

Carbonic acid,
Sulphureted hydrogen,.

Free carbonic acid,
Carbonate of soda,
Sulphate of soda,
Muriate of soda,
Alumine,
Carbonate of lime,
Oxide of iron,
Carbonate of magnesia,

130 grs.

189 -66

57

66

145 66

62

66

116

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11

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38

66

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Total, 748

There are seven springs at Vichi, ranging in temperature from 72° to 112° Fahr. The proportions of the saline ingredients vary in each. All contain, however, carbonic acid, carbonates of lime, magnesia, soda, sulphate of soda and muriate of soda. Of the cold carbonated waters, those of Seltz, situated on the Rhine, nine leagues north-east of Strasburg, are the most celebrated. The artificial Seltz water is made as follows:

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bonates of soda, lime and magnesia, mu- springs in France are those or Mont d'Or riate and sulphate of soda and silex. The and of Vichi. The former were known gases are in the following proportions :— to the Romans. There are four principal springs at Mont d'Or, the temperature of 51.25 three of which are decidedly thermal, 28.26 and stand respectively at 107°, 109° and 20.49 113° Fabr.; while the fourth is of the low temperature of 52° Fahr. An analy100.00 sis of one of these springs gives, Their medicinal qualities have been long well known. They are adapted to all chronic cutaneous disorders, asthmatic affections, chronic rheumatism, dyspepsia, diseases of the uterus, stiffness, weakness and contraction of the limbs from gun-shot wounds. Their use is external and internal. Those waters of the present class existing in the U. States, which are the best known, are the White Sulphur springs of Virginia. They are situated in the county of Greenbriar, in a hilly and mountainous region of country, thirty-seven miles in a south-westerly direction from the Hot springs. The water is very cold, and by its taste indicates an abundance of saline matter in its composition. It deposits largely a whitish matter, consisting chiefly of sulphur. These waters, besides proving efficacious in those diseases enumerated above, have been much resorted to by invalids suffering from the slow fever, following remittent, bilious, or ill-cured intermittent fevers. Under the present class must be mentioned the Salt Sulphur spring in Monroe county, and the Red Sulphur spring in Giles county, Virginia. The last mentioned enjoys much celebrity in cases of pulmonary consumption in all its stages. (See Virginia.) Numerous springs of the sulphureous class occur throughout the longitudinal range of Tennessee from west to east, from Nashville on to the Virginia line. In Kentucky, also, the Olympian springs, situated fifty miles east of Lexington, among the western ranges of the Alleghany mountains, are deserving of mention; likewise the Blue Licks, which occur on the banks of the Licking river, forty miles north-east of Lexington, on the main road from that place to Maysville. The carbonated waters, whose characteristic is the predominance of carbonic acid, are both cold and thermal. Their medical use is most advantageously displayed in allaying the thirst and heat of feverish action which accompany a disturbed state of the stomach, and inflammation of the liver and other viscera, and in subduing irritation of the kidneys, and checking copious discharges. The two inost celebrated thermal acidulous

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The best example of this class afforded by the U. States is found in the Sweet springs, Monroe county, Virginia. The springs rise on the north side of a large mountain. Their temperature is 73° Fahr. The name is calculated to convey an erroneous impression of their taste, which is not sweet, but like a solution of a small quantity of a calcareous or magnesian carbonate: the excess of carbonic acid gives, however, the waters a briskness productive of a very different effect on the palate from what an imperfect mixture of the earths would produce. Chalybeate waters owe their characteris tic properties, both chemical and medici nal, to an impregnation of iron, in the state of an oxide, which is held in solution by carbonic acid. They are limpid, inodorous, and have a peculiar styptic taste. Exposed to the air, they become covered with an iridescent pellicle, and a quantity of ochrey matter subsides, the water at the same time losing its taste.

The effects of waters of this class are modified by the quantity of carbonic acid in excess, and of saline ingredients. One of the purest of the class is that of Tunbridge, in England. The waters of Tunbridge Wells are not strong, however, with saline or ferruginous ingredients, one gallon containing only seven and a half grains. They are found particularly useful in dyspepsia, uterine debility, cutaneous complaints and gravel. The most noted chalybeates in Europe are the Spa, in the kingdom of Belgium, and Pyrmont, in Westphalia. Spa is a small town, situated in a mountainous district, which forms part of the forest of Ardennes. It is ten leagues from Aix-laChapelle, six from Liege, and seventyfive from Paris. The edifices and places of public amusement are on a magnificent scale. There are seven springs, of which number that of Pouhon is the principal. It contains, according to Bergmann, in one hundred pounds of the water,

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A hundred cubic inches of the water contain forty-five cubic inches of carbonic acid gas. The action of these waters is tonic, aperient and cooling; they strengthen muscular action, and are efficacious in diseases proceeding from weakness and relaxation of the tissues. Pyrmont is situated near the river Weser, four leagues from Hamelet, in Westphalia. It has six principal springs, all of the temperature of 55° Fahr. The Pyrmont springs contain, in one hundred pounds of the water,

Crystallized muriate of soda, 122 grs.
Muriate of magnesia,
Crystallized sulphate of soda, 547
Carbonate of iron,
Carbonate of lime, .
Carbonate of magnesia,
Resinous principles,

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These waters, if drunk in large quantities, or taken by persons whose stomachs are rather irritable, operate as an aperient, and. at the same time, have a powerful effect as a diuretic, and are of eminent service in all those chronic affections in which chalybeate medicines are employed. The following springs at Saratoga, viz. the Flat Rock, Columbian, High Rock, and Ellis's springs, differ but little, except in containing an excess of carbonic acid, from the Ballston Spa. Next to the springs just mentioned deserves to be noticed the Bedford springs, in Pennsylvania. They are situated in Bedford county, 195 miles from Philadelphia, and 931 from Pittsburgh. One gallon of the water contains, according to doctor Church,

Sulphate of magnesia,
Sulphate of lime, .
Muriate of soda,
Muriate of lime,
Carbonate of iron,

134

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Carbonate of lime,

105

66

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339 66

9

1605

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One hundred pounds of this water contain fifteen hundred grains of carbonic acid. It is said to be eminently tonic. In the U. States there are a great number of chalybeate springs; the most noted of which are those of Ballston. Indeed, the waters of Saratoga might be included

80 grs.

14

66

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Carbonic acid gas, seventy-four cubic inches. Temperature of the water, 55 Fahr. It contains less free carbonic acid than the New York springs, and on this account is less immediately exhilarating; but it is also less stimulating, and not so liable to affect the head as the latter. As a saline chalybeate, it contains less com

on salt than these, but has, in return, a decided impregnation with Epsom salt, by which it is better fitted to act on the

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