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Document Max. Freq Min. Freq
A Dictionary of Greek and Roman biography and mythology (ed. William Smith) 48 48 Browse Search
Polybius, Histories 9 9 Browse Search
Knight's Mechanical Encyclopedia (ed. Knight) 6 6 Browse Search
Titus Livius (Livy), Ab Urbe Condita, books 26-27 (ed. Frank Gardner Moore, Professor Emeritus in Columbia University) 4 4 Browse Search
M. Tullius Cicero, De Officiis: index (ed. Walter Miller) 2 2 Browse Search
Titus Livius (Livy), Ab Urbe Condita, books 31-34 (ed. Evan T. Sage, Ph.D. Professor of Latin and Head of the Department of Classics in the University of Pittsburgh) 2 2 Browse Search
Appian, The Foreign Wars (ed. Horace White) 2 2 Browse Search
Strabo, Geography (ed. H.C. Hamilton, Esq., W. Falconer, M.A.) 1 1 Browse Search
Titus Livius (Livy), Ab Urbe Condita, books 28-30 (ed. Frank Gardener Moore, Professor Emeritus in Columbia University) 1 1 Browse Search
Titus Livius (Livy), Ab Urbe Condita, books 31-34 (ed. Evan T. Sage, Ph.D. Professor of Latin and Head of the Department of Classics in the University of Pittsburgh) 1 1 Browse Search
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Browsing named entities in Knight's Mechanical Encyclopedia (ed. Knight). You can also browse the collection for 212 BC or search for 212 BC in all documents.

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previously. The first striking or audible notification of the hour, on record, is the clepsydra or water-dial of Plato, 372 B. C., which, by the agency of water, sounded upon organ-pipes the hour of the night when the index could not be seen. The contrivance is mentioned by Athenaeus of Egypt, a distinguished Greek writer of the third century, and author of the Deipnosophistae. See 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 not known. The early indications are as follows: — A. D. 760, a clock presented by Pope Paul I. to Pepin, o
mewhere in Tartary about the eleventh century (some say the thirteenth), is cited as particularly skilful in blowing up his enemies. He stuffed — so says the legend — copper figures with explosive and combustible materials which were emitted at the mouths and nostrils of the effigies, making great havoc. The Danish historian, Saxo Grammaticus, A. D. 1200, gives an account of a similar contrivance, used by a Gothic king. The devices of Archimedes, who defended Syracuse from the Romans, 212 B. C., were mechanical or optical, and do not seem to have involved chemical compounds. Green-house. 1. (Pottery.) A house moderately warmed, where some kinds of green-ware are placed to become partially dried before taking to the hothouse, where the drying is completed by strong heat. The ware is then arranged in seggars and fired in the kiln. 2. (Horticulture.) A plant-house, with glass roof and sides, with facilities for maintaining an artificial temperature and the necessary
any, is a hen's egg, used by a farmer's wife to test the strength of lye for making soap. When it floats as large as a quarter-dollar above the liquid the strength is satisfactory. Others test it by its action on a feather. Small hollow glass spheres called bubbles are also used in testing spirits, the rate at which they ascend therein being a gage of the gravity of the liquid. The hydrometer was in all probability invented by Archimedes, who was killed in the storming of Syracuse, 212 B. C. His discovery of the mode of ascertaining specific gravity by displacement of liquid is referred to by many writers of Europe, Asia, and Libya. Seneca, Pliny, and Galen, who flourished during the first and second centuries of our era, and whose writings refer to the methods then in use of ascertaining the specific gravity of solids and fluids, appear unacquainted with the hydrometer, though the instrument is clearly described by Priscian, who died about A. D. 528. Synesius of Ptolema
t is hardly as good a one as that shown at k, which is a plow of the Greek occupation over 2,000 years since, before Syracuse fell under the attack of Marcellus, 212 B. C. It still lacks the mold-board. n shows the modern Roman plow, with a broad flat share. The diverging wings form a wedge which divides and turns over the soil tf Louis XIV., — not so very long after the good burgher of Magdeburg had set the ball rolling again. What Archimedes did for the fleet of Marcellus at Syracuse, 212 B. C., Proclus did for the ships of Vitalian at Constantinople some 700 years afterward, and Buffon performs the same feats with burning mirrors in a peaceable way, abe of Pythagoras, about 516 B. C. It does not appear to have been used by the ancient Egyptians. The combination of pulleys is ascribed to Archimedes, who died 212 B. C. Vitruvius described the pulley. He refers to the sheaves (orbicuti) in the blocks (trochlea), and defines the system by the aggregate number of sheaves in th