valuable machine of wonderful construction, worth more than 5000 ducats. For it appeared to resemble internally a celestial globe in which figures of the sun, moon, and other planets, formed with the greatest skill, moved, being impelled by weights and wheels, so that performing their course in certain and fixed intervals, they pointed out the hour, night and day, with infallible certainty; also the twelve signs of the Zodiac with appropriate characters, moved with the firmament, contained within themselves the course of the planet.' To whom the high honour belongs of inventing the clock is, to use a not unknown phrase, 'lost in the mists of antiquity.' All the ancients who were reported as skilful in mechanics seem to have obtained a modicum of credit as clock-inventors. Archimedes and Posidonius before, the Christian era, Boëthius in the 5th century, Pacificus about the middle of the 9th, Gerbert at the end of the 10th, Wallingford near the beginning of the 14th, and Dondi at the end of the 14th, have each in their turn been asserted to be the inventors of the clock. The sphere of Archimedes, made 200 B.C., as mentioned by Claudian, was evidently an instrument with a maintaining power but without a regulator, and therefore would not measure time in any other manner than as a planetarium, turned by a handle, measures, or rather exhibits, the respective velocities of the heavenly bodies; and the same may be said of the sphere of Posidonius, as mentioned by Cicero ('De naturâ Deorum'). The clock of Boëthius was a clepsydra, as was also that of Pacificus, according to some, for Bailly in his History of Modern Astronomy asserts that Pacificus was the inventor of a clock going by means of a weight and a balance, and if so the invention must be ascribed to Pacificus; but Bailly gives no authority for his assertion. Gerbert's horologe is said to have been merely a sun-dial, and Wallingford's horologe, called the Albion, must have as much resembled a planetarium as a clock, for the motions of all the heavenly bodies appear to have been conducted by the maintaining power, whatever that was, without controlling mechanism. This instrument, made in 1326, is also described as having shown the ebb and flow of the sea, the hours, and the minutes.