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Knight's Mechanical Encyclopedia (ed. Knight), A. (search)
the water across valleys, — their purpose probably did not require it, — but gave their aqueducts a sinuous course, winding around the mountains and through the valleys with sufficient inclination to allow the water to flow freely. The French aqueducts referred to in this article are most of them of great magnitude and importance, and the most stupendous work of the kind ever projected originated in France. This was the aqueduct of Maintenon, which was undertaken in 1684 and abandoned in 1688, during which time 22,000,000 francs are said to have been expended upon it. It was intended to have brought water from the river Eure at Pongoin to Versailles, a distance of nearly 25 leagues, and embraced an arcade of masonry 16,090 feet in length, comprising three tiers of arches at its highest part. The illustrations (Fig. 291) exhibit to the same scale, — 1. The Pont du Gard Aqueduct, at Nismes, under which the river Gardon passes, and which was built by the Romans, possibly by Agr<
Knight's Mechanical Encyclopedia (ed. Knight), B. (search)
h ascends in the tube by the pressure of the atmosphere. Changes in the weight of the atmosphere raise or lower the hight of the mercurial column; and a graduated scale alongside the tube, and embracing the range of motion, enables the reading of the variations. The wheel barometer has a recurved tube in which the mercury ascends and descends, thereby actuating a float which connects by a cord to the axis of an index-finger, which rotates on a graduated dial. It was contrived by Hooke in 1688, the year that the great Dutchman, William of Orange, came to England. The pendent or marine barometer is suspended on gimbals, which enable it to maintain its verticality during the rolling and pitching motions of a ship, and has a contraction at the bottom of the tube to obviate oscillations of the mercury. It was introduced about the year 1698-1700. The invention of the aneroid barometer is attributed to Conti, 1798, or to Vidi, 1804. In the aneroid barometer (which, as its name
Knight's Mechanical Encyclopedia (ed. Knight), C. (search)
n Holland for floating vessels over the sands and bars. The length of one of these camels is 127 feet; the breadth at one end is 22 feet, at the other 13 feet. The interior is divided by water-tight partitions. A vessel drawing 15 feet of water could, by this means, be made to draw only 11 feet, and the largest man-of-war in the Dutch service could be made to pass the sand-bars of the Zuyder Zee. The in- vention, in Holland, is ascribed to Meuves Meindertszoon Bakker, of Amsterdam, about 1688. The approaches to Amsterdam had always been obstructed by sand-bars and similar obstacles, so that vessels of heavy draft were forced to receive and deliver the greater part of their cargoes several miles below the city, which was effected by means of lighters. To enable large vessels to pass the shoals, previous to the invention of the camel, large chests filled with water were fastened to their bottoms, and the water was afterwards pumped out. This method was attended with great diffic
Knight's Mechanical Encyclopedia (ed. Knight), D. (search)
entions a print in Vegetius on War, published in 1511 and 1532, representing a diver with his cap, from which rises a long leather pipe provided with an opening above the surface of the water. Lorini on Fortification, 1607, shows a square box, bound with iron, furnished with windows and a seat for the diver. Kessler in 1617, Witsen in 1671, and Borelli in 1679, gave attention to the subject and contributed to the efficiency of the apparatus. A diving-bell company was formed in England in 1688, and the operators made some sucessful descents on the coast of Hispaniola. In 1664, cannon were recovered from wrecks of the Spanish Armada by the Laird of Melgim, near the Isle of Man, but not sufficient to pay. Previous unsuccessful attempts had been made by Colquhoun, of Glasgow, who depended for air upon a leathern tube reaching above the surface of the water. Dr. Halley, in 1715, improved the diving-bell by a contrivance for supplying it with fresh air by means of barrels lowered from
Knight's Mechanical Encyclopedia (ed. Knight), G. (search)
om coal dates in the seventeenth century, and the early examples of its manufacture and use are as follows: — Dr. Clayton, rector of Crofton, England, distilled illuminating gas from coal, and detailed the experiment to his friend Dr. Boyle, in 1688. Dr. Boyle announced it to the Royal Society before his death, which happened in 1691. Dr. Clayton obtained what he called an uncondensable spirit, which, as it issued in a jet, was caught in a bladder and used for experiments; the gas being repeathe valve relatively to its seat, and this graduates the area of opening to the pressure. Gas-re-tort′. The chamber in which carbonaceous matter is distilled to produce illuminating gas. Dr. Clayton distilled illuminating gas from coal in 1688; the Philosophical Transactions of 1739 refer to the fact. Dr. Hales in 1726 made a quantitative experiment as to the cubic inches of gas obtained from a given number of grains of coal. Lord Dundonald's patent of 1786 was for ovens or retorts in
Knight's Mechanical Encyclopedia (ed. Knight), M. (search)
ticularly in France, where it was discovered that glass could be cast into much larger plates than had been before prepared by blowing and rolling, destroyed the ancient supremacy of Venice in this art. An unsuccessful attempt was made in France as early as 1634 to establish glass-houses for manufacturing mirrors, and in 1665 Nicholas de Mayer obtained a patent from the French government, and proceeded to erect works for the purpose. This patent was in 1684 renewed for thirty years, but in 1688 Abraham Thevart succeeded in casting at Paris plates of a size which astonished all who saw them; they were 84 inches long and 50 broad, while the largest of those previously made had not exceeded 45 or 50 inches in length. Among the more remarkable modern mirrors may be cited several of from 20 to 36 inches diameter. One made by Villette was tested by Drs. Desaguliers and Harris. It was composed of an alloy of tin, copper, and bismuth. It was 47 inches in diameter, and was ground to a
Knight's Mechanical Encyclopedia (ed. Knight), P. (search)
of the University of Paris. It appears that wall-paper, as a substitute for tapestry or hangings, began to come into vogue about the year 1640. It does not appear that the paper manufacture flourished in England until after the revolution of 1688, as we find that in 1663 England imported from Holland alone paper to the amount of £ 100,000. This hardly preceded the establishment of paper manufactories in America, as we find that William Rittinghuysen, anglicized Rittenhouse, — a name aftition of an intaglio for the printer. Plate-glass. Plates of glass covered with tinfoil, for mirrors, were made in Venice during the sixteenth century, but the invention of casting glass to form plates is due to Abraham Thevart. In the year 1688, plates 84 × 50 inches were cast by his process at St. Gobin, in Picardy. A plate-glass manufactory on a small scale was established at Lambeth in 1673, but the manufacture does not appear to have flourished in England until it was undertaken b
Knight's Mechanical Encyclopedia (ed. Knight), R. (search)
orcing in the air; the flotative power of the caisson thus lightened lifting the vessel to the surface. The camel has long been used in Holland for floating vessels over the bars of rivers. The invention is credited to Bakker of Amsterdam, about 1688, the year that the great Prince of Orange came over to England and superseded the last of the Stuart kings. The camel consists of twin hollow vessels, so arranged that they can be applied on either side of the ship's hull. They are made water-ti far above its level. It is used with effect on hard, smooth ground against bodies of troops or such obstacles as abattis; and also upon water, either with round shot or rifle balls. It was introduced by Vauban at the siege of Philips burg, in 1688. Rico-chet′--shot. （Gunnery.) A bounding or leaping shot, fired at low elevation with small charge. Rid′dle. A sieve with coarse meshes, used in preparatory separation, as:— 1. The riddle of a grain-separator which removes the co
Knight's Mechanical Encyclopedia (ed. Knight), T. (search)
the bridge, doing immense damage in the vicinity September 30, 1628, the English employed floating tin caissons of powder against the French at Rochelle. One exploded against a vessel without seriously damaging it. The others were intercepted. In the afternoon come the German, Dr. Knuffler, to discourse with us about his engine to blow up ships. We doubted not the matter of fact, it being tried in Cromwell's time, but the safety of carrying them in ships.—Pepys's Diary, 1662. In 1688 an immense floating bomb was prepared by the French against the port of Algiers, but was not used. In 1693-95 similar contrivances were used by the English in besieging St. Malo, Dieppe, and Dunkirk, without serious damage. In 1770 the Russians burned the Turkish fleet in the port of Tchesme, and destroyed the fortifications by the shock of the explosion. In 1804 the loaded catamarans of Fulton were used by the English against the French fleet off Boulogne. But little damage was don
Knight's Mechanical Encyclopedia (ed. Knight), U. (search)
pie; also a testern or cloth of state for a prince; also a kind of round fan or shadowing that they vse to ride with in summer in Italy; a little shade ), and by Ben Jonson, in a comedy, 1616, and were used by ladies in the time of Queen Anne. Du Cange mentions the custom of contracting and expanding them. Cotgrave, in his History of the English and French tongues, speaks of the French ombrelle. Montaigne refers to its use in Italy. M. de la Loubere, ambassador from France to Siam, 1687-88, states that the King of Siam had a triple umbrella, several frames and covers being fastened to the same stick. This was a royal right. The nobles had single umbrellas. Common people stood in the sun. The Siamese monks (Talapoins) had palm-leaves rut and folded, so that the stem formed a handle. Tavernier describes the umbrellas on each side of the throne of the Great Mogul, and those at the court of the king of Ava, whose title was, and perhaps is, King of the White Elephant and Lord o
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