precision, owing to its being reckoned by the sun's daily return to the meridian, which differs, though inconsiderably, by reason of the obliquity of the ecliptic, and the sun's unequal motion in it. The Romans were perfectly sensible of this inequality, but unable to apply such knowledge to the regulation of their Clepsydræ; and although there are many passages in their best authors alluding to this difference, it is to be remarked, that their expressions of Summer and Winter hours are generally to be taken in a Military sense, as allusive to the time it was light, viz. From sun-rise to sun-set, which being divided into four watches, the Summer hours consisted each of about a 12th part of fifteen hours, and those of Winter of only about a 12th part of eight hours; and so, of course, in proportion for all intermediate periods. VEGETIUS, in his Treatise on Military Institutes, addressed to the emperor VALENTINIAN, which may be adduced as one instance, remarks, "That the soldiers ought to be drilled to march in order, and with the military step, at the rate of 20 miles in five Summer hours; and at the quickest pace, 24 in the same space of time." The following EQUATION TABLE, adapted to the second year after every Leap-year, and thereby taking the medium, shews to the nearest full minute, how much a clock should be faster or slower than an accurate sun-dial; viz. The origin of the term HOUR has been differently explained, some authors deriving it from Hora, a sur-name given to the sun, the parent of Time, and called by the Egyptians Horus, whence, through the Latin, comes our expression of horologe, for an instrument to measure dura❤ tion, and the French Heure for an Hour, Horloge for a clock, &c.: others derive the term from the Greek oggi, to terminate or distinguish ; while it is generally believed to have been introduced by TRIS MEGISTUS, from an observation made by him, that an animal named Cynocephalus, was accustomed to void its water twelve times each day, and as often each night, at equal intervals, and hence originally called qugo", the Greek word for such secretion. The antient Hebrews did not at first divide their days into hours, though they appear to have adopted that usage for some time prior to the Incarnation of our LORD, and to have made the day consist of twelve parts: "Are there not," says St. MARK, c. xiii. v. 35, "twelve hours in the day?" From the Hebrews the Greeks borrowed this partition of time, and the Romans from the Greeks, but not until some period subsequent to the first Punic war. Whether the Jews adopted this regulation from the Egyptians, as is commonly supposed, or the Egyptians from them, cannot be determined. The unequal hours are in general distinguished by the epithet of Planetary, from a supposition of the antient Astronomers, that the seven planets in our system, the only ones known to them, alternately presided over the several hours: the first hour of the first day of the week, was considered to be under the rule of the Sun, the second under that of Venus, the third of Mercury, the fourth of the Moon, the fifth of Saturn, the sixth of Jupiter, and the seventh of Mars; and the Sun after such regular rotation governed the eighth hour, Venus the ninth, and so on through the whole twenty-four hours. As the Sun was presumed to be the guardian of the first hour of the first day, the whole of that day was placed under his peculiar care, and accordingly named Dies Solis, or the day of the Sun, à Dij, conformably to a superstitious belief, that the planets (see page 100) were gods; and as the first hour of the second day came to the Moon, that planet was presumed to rule the second day; Mars the third, and the other five in regular succession, as shewn by the two following Tables: the first formed upon the principle of the division of the day into two portions of twelve parts each, as was the practice when the planets had their several hours assigned to them; the other, according to the modern method of computing, by equal divisions consisting each of a precise twenty-fourth part of the Nychthemeron, or day and night combined; viz. |