The French historians describe a clock sent to Charlemagne in the year 807, by the famous eastern caliph, Haroun al Raschid, which was evidently furnished with some kind of wheelwork, although the moving power appears to have been produced by the fall of water. This clock was a rather wonderful affair, and excited a great deal of attention at the French court. In the dial of it were twelve small doors forming the divisions for the hours, each door opened at the hour marked by the index, and let out small brass balls, which, falling on a bell, struck the hours--a great novelty at that time. The doors continued open until the hour of twelve, when twelve figures representing knights on horseback came out and paraded round the dial plate. REMARKABLE EVENTS, INVENTIONS, &c. Memnon, the Egyptian, invents the letters, in the year 1822, _before_ Christ. The Alexandrian library, consisting of 400,000 valuable books, burnt by accident, B. C. 52. Silk first brought from India, 274: the manufactory of it introduced into Europe by some monks, 551: first worn by the clergy in England, in 1534. Glass invented in England by Benalt, a monk, A. C. 400. The University of Cambridge founded A. C. 915. Paper made of cotton rags was in use, 1000; that of linen rags in 1170: the manufactory introduced into England, at Dartford, 1588. Musical notes invented, 1070. Justices of the Peace first appointed in England in 1076. Doomsday-book began to be compiled by order of William, from a survey of all the estates in England (and finished in 1086), 1080. Glass windows began to be used in private houses in England in 1186. Surnames now began to be used, first among the nobility, in 1200. The houses of London and other cities in England, France, and Germany, still thatched with straw in 1233. Tallow candles so great a luxury, that splinters of wood were used for lights, 1298. Wine sold by apothecaries as a cordial, 1298. Gunpowder and guns first invented by Swartz, a monk of Cologn, 1340; Edward 3rd had four pieces of cannon, which contributed to gain him the battle of Cressy, 1346; bombs and mortars were invented in the same year. Cards invented in France for the king's amusement in 1391. Windsor Castle built by Edward 3rd, 1386. Guildhall, London, built 1410. About 1430, Laurentius, of Haarlem, invented the art of Printing, which he practised with separate wooden types. Guttenburg afterwards invented cut metal types: but the art was carried to perfection by Peter Schoeffer, who invented the mode of casting the types in matrices. Frederick Corsellis began to print at Oxford, in 1468, with wooden types; but it was William Caxton who introduced into England the art of printing with fusile types, in 1474. Shillings first coined in England, 1505. Silk stockings first worn by the French King, 1543; first worn in England by Queen Elizabeth in 1561. Tobacco first brought from Virginia into England, 1583.