stonished for one hour, Chaldean time, which is not astonishing, considering the critical nature of the message he had to deliver.
Distinct intimation of the hours is given in connection with the setting up of the dial in the Quirinus at Rome, 293 B. C. The hours were called through Rome by public criers, as they were at night by watchmen, within the memory of some of us.
They return at evening; they make a noise like a dog, and go round about the city. — Psalms LIX. 6.
Clocks are not veSee clepsydra.
Wheel-work set in motion by springs and weights was known in the time of Archimedes (287-212 B. C.), and applied to mechanical engines and toys.
The graduated dial, the shadow of the gnomon marking hours, was known in Rome 293 B. C.
Two more things were necessary to make a clock: —
1. To join the wheels to a pointer which traversed the dial.
2. To contrive a mode of regulating the speed of the going works.
When these two features were united to form a clock is
august procession of philosophers during the seven centuries which separated Aristarchus from Hypatia.
On the instrument, which had a plane parallel to the equator and a gnomon parallel to the earth's polar axis, Hipparchus, 150 B. C., learned the length of the year, that the four quarters of the year are not of equal length, and also observed the precession of the equinoxes.
See armillary sphere.
Before the time of the erection of a sun-dial in the Quirinus by L. Papyrius Cursor, 293 B. C., the time was called by watches, which divided the time between the rising and setting of the sun. About thirty years after, the Consul Marcus Valerius Messala brought to Rome a dial from the spoils of Catania, in Sicily, and this he placed on a pillar near the rostrum; but, not being calculated for the latitude of Rome, it was inexact.
The obelisk erected by Augustus in the Campus Martius was brought by his orders from Egypt.
It was originally hewn for Pharaoh Sesothis, according to P
the experiences of an Israelite of Naphtali, a prisoner in Nineveh in the reigns of Shalmanezer and Sennacherib.
The statement of Herodotus that the Greeks derived the sundial from the Chaldeans is no doubt correct.
In the time of Ahaz, the communications between Assyria and Palestine were open and well traveled, as the Israelites well knew and felt.
Homer describes the sun-dial, 950 B. C.
The dial was introduced in Athens by Meton, 433 B. C.
By L. Papirius Cursor into Rome, 293 B. C.
Hipparchus used a dial at Alexandria, 130 B. C.
Augustus set one up on a magnificent scale in the Campus Martius.
(Fr. Suint-de-verre.) A saline scum which rises to the surface of fused glass in the pot, and is skimmed off. Called also glass-gall; sadwei.
A process for grinding and abrading hard substances by the impact of a stream of sand propelled by an air or steam jet.
In depolishing glass, the stream of sharp sand is projected by