13. The earliest historical notice of gold and silver is found in the thirteenth chapter of Genesis, where it is stated that Abraham returned to Canaan from Egypt, "rich in cattle, in silver, and in gold." This event took place about 1920 years before Christ, it being but little more than 400 years after the deluge. From the authority of the same book, we also learn, that during the life of this patriarch, those metals were employed as a medium of commercial intercourse, and as the materials for personal ornaments, vessels, and utensils.

14. From the preceding facts, we have reason to believe that gold and silver were known to the antediluvians; for, had not this been the case, they could hardly have been held in such estimation so early as the time of Abraham. In short, they were probably wrought even in the days of the original progenitor of the human race, as was evidently the case with iron and copper.

THE CLOCK AND WATCH MAKER.

1. The great divisions of time, noted by uncivilized men, are those which are indicated by the changes of the moon, and the annual and diurnal revolutions of the earth; but the ingenuity of man was very early exercised in devising methods of measuring more minute periods of duration.

2. The earliest contrivance for effecting this object was the sun-dial. This instrument was known to the ancient Egyptians, Chaldeans, Chinese, and Bramins. It was likewise known to the Hebrews, at least as early as 740 years before Christ, in the days of Ahaz the king. The Greeks and the Romans borrowed it from their Eastern neighbors. The first sun-dial at Rome was set up by Papirius Cursor, about 300 years before Christ. Before this period, the Romans determined the time of day by the rude method of observing the length of shadows.

3. The sun-dial, as it is now constructed, consists of a plate, divided into twelve equal parts, like the face of a clock, on which the falling of a shadow indicates the time of day. The shadow is projected by the sun, through the intervention of a rod or the edge of a plate stile erected on the plane of the dial. But, since the dial was useful only in the clear day, another instrument was invented, which could be used at all times, in every variety of situation; and to this was given the name of clepsydra.

4. This instrument is supposed to have been invented in Egypt; but, at what period, or by whom, it is not stated. Its construction was varied, in different ages and countries, according with the particular modes of reckoning time; but the constant dropping or running of water from one vessel into another, through a small aperture, is the basis in all the forms which it has assumed. The time was indicated by the regularly increasing height of the water in the receiving vessel.

5. The clepsydra was introduced into Greece by Plato, near 400 years before Christ, and, about 200 years after this, into Rome, by Scipio Africanus. It is said that Pompey brought a valuable one from the East, and that Julius Cæsar met with one in England, by which he discovered that the summer nights were shorter there than in Italy.

6. The use which Pompey made of his instrument, was to limit the length of speeches in the senate. Hence he is said, by a historian of those times, to have been the first Roman who put bridles upon eloquence. A similar use was made of the clepsydra in the courts of justice, first in Greece, and afterwards in Rome.

7. A kind of water-clock, or clepsydra, adapted to the modern divisions of time, was invented near the middle of the seventeenth century; and these were extensively used, in various parts of Europe, for a considerable time; but they are now entirely superseded by our common clocks and watches, which are far more perfect in their operation, and, in all respects, better adapted to the purposes to which they are applied.