HOROLOGY is the art of constructing machines for suring time. The word is derived from the Greek (through the Latin horologium,) compounded of Zfa, all hour, and Avyw, to read or point out ; hence Zfoopyrov, a machine for indicating the hours of the day. Long before sun-dials were invented, clepsydrx, or water clocks, had been made in the most remote periods of antiquity, and were used in Asia, China, India, ChaIdea, Egypt, and Greece, where Plato introduced them. Julius Cxsar found them even in Britain, when he carried his arms thither ; and it was by them he observed, that the nights•in this climate were shorter than those in Italy : (See his Commentaries, lib. v. xiii.) Toothed wheels, although known a considerable time before, were first applied to clepsydra by Ctesibius, a native of Alexan dria, who lived I40 years before the Christian era. At what time, or by whom, was invented the clock with toothed wheels, crown wheel 'scapement, and the regu lator in the form of a cross suspended by a cord, with two weights to shift on it, can now only be guessed at, as no positive information on this subject has been handed down to us. It was this kind of clock, a large turret one, which Charles V. king of France, surnamed the Wise, caused to be made at Paris by Henry Fick, who was sent w for from Germany for the express purpose, and which was put up in the tower of his palace about the year 1370. Julien le Roy, who had seen this clock, has given some account of it in his edition of Sully's Regle Artificielle the Temps, Paris 1737: (See Plate CCC. Fig. I. and the Description of the Plates at the end of the volume.) Be fore a clock could be brought even to the state of the one made by Vick, there must have been many alterations and progressive improvements upon•that which had first been projected, so that it must have been invented at least two or three centuries before Vick's time. As the same word for a sun-dial among the Greeks and Romans was also that for a clock, disputes have arisen, whether the horologia of Pacificus and of Gerhert were sundials or clocks. Father Alexander asserts that the horologium of Gmbert was a clock ; while Hamberger supposes it to have been a sun-dial, from the pole-star having been em ployed in setting it. Pacificus was archdeacon of Verona about the year 850. Gerbert was pope, under the name of Silvester 11. and made his clock at Magdeburg, about the year 996.
Richard of \Valingford, abbot of St Albans in England, who flourished in 1326, by a miracle of art constructed a clock, had not its equal in all Europe, according to the testimony of Gesner. Leland too, an old English
author, informs us, that it was a clock which sheaved the course of the sun, moon, and stars, and the rise and fall of the tides ; that it continued to go in his own time, which was about the latter end of Henry the Seventh's reign ; and that, according to tradition, this famous piece of mechanism was called :Mien by the inventor.
" In 1382," says Father Alexander, " the Duke of Burgundy ordered to be taken away from the city of Courtray, a clock which struck the hours, and which was one of the best known at nett time, either on this side or beyond seas, and made it be brought to Dijon, his capital, where it still is in the tower cf Notre Dame. These are the three most ancient clocks ttlat 1 find, after that of Gerhert," " We know no person," continues th'is author, " more ancient, and to whom we can more justly attribute the in vention of clocks with toothed wheels, than to Gerbert. He was born in Auvergne, and was a monk in the abbey of St Gerard d'Orillac, of the order of Saint Bennet. His abbot sent him into Spain, where he learned astrology and the mathematics, in which he became so great a mas ter, that, in an age when these sciences were little ktioWn, he passed for a magician,* as well as the Abbot Trithe tnius. Front Spain he came to Rome, where he received the abbacy of Bobio in Italy, founded by Saint Columbus ; but the poor state of its lunds compelled him to return to France. The reputation of his learning and uncommon genius, induced Adalberon, Archbishop of Rheims, to establish him, in 970, as rector of the schools there, and at the same time to make him his private secretary. It was near the end of the tenth century, about the year 996, when he made at Magdeburg this clock, so wonder ful and surprising, by 712C(1118 of weights and wheels. He was Archbishop of Rheims in 992, a situation which he held 'during three years, then archbishop of Ravenna in 997, and at last sovereign pontiff, under the name of' Sil vester 11. in 999 ; and he died at the beginning of the filth year of his pontificate, in 1003." The clock con structed by Gerhert seems to have been made after he left Rheims, and before his appointment to Ravenna; and it is highly probable, that this was the period when clock making was introduced into Germany.