diverted, or made in an artificial channel to which the river was subsequently transferred.
Either plan was possible in that country, and the former was tried, to the cost of the Babylonians, by Cyrus, many centuries after Nitocris.
Ancient bridges of great magnitude exist in China.
This ingenious people constructed them of wood, stone, chains, and ropes, before history commenced to be written in Europe.
The great wall of China (Wan-li-chang, the myriad-mile-wall) was finished about 220 B. C., and has many stone bridges over the various streams which it crosses in its course of 1,250 miles. It puts into the shade the British wall of Agricola, which united the Tyne and the Solway, 80 miles; and the other Roman wall which united the Forth and Clyde, 36 miles.
The Egyptians built no permanent bridges across the Nile, but were familiar with framing trestlework, and with ponton and draw bridges; the latter are seen frequently in their paintings representing fortified towns, siege
d a pointer finger on a figured dial.
5. A clepsydra in which the escaping water turned a wheel which communicated motion to a hand on a dial.
These devices were subject to many difficulties such as the evaporation of the water, which affected those depending upon the measured amount, and the unequal rate of flow at different stages of fullness of the discharging-vessel.
At what period toothed gearing was invented cannot be readily ascertained.
Archimedes used it 220 B. C., and probably saw it in Egypt.
Sand, as the flowing material, is stated by some authorities to have been introduced in France about the time of Charlemagne, but this is an error.
On an ancient bas-relief in Rome an hour glass is placed in the hands of Morpheus.
Athenaeus says that the ancients carried portable hour-glasses with them.
The term translated hour-glass does not warrant the idea that glass was used.
The probable material was horn, or the mineral then so much used for
ottage of this description, combining all the requirements of health, decency, and comfort, is $425. See also list under masonry.
The walls of Babylon were possibly 75 feet high.
They had been gradually decreasing in height since the time of Herodotus, who reported them 200 royal cubits = 337 feet (English); Ctesias, 300 feet; Xenophon, 100.
It is probable that the reputed dimensions decreased as more reliable estimates were transmitted.
The Chinese wall was built by Chi-hwang-ti, 220 B. C. The feudal system was about that time in course of demolition in China, and was accomplished by the Han dynasty.
The process is now being repeated in Japan.
This great wall is 1,200 miles long, from 20 to 25 feet high, and from 15 to 20 feet broad.
It was built as a barrier against the hordes of Tartar cavalry, and was everywhere constructed of the materials found in the immediate neighborhood.
Fig. 7027 is a view of a portion of the Great Chinese Wall, at a point three days jour