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GERMAN JEW OF THE EARLY 16TH CENTURY

See Jews: Germany THE GREAT SYNAGOGUE AT. WARSAW, POLAND

See Jews: Poland BARON MAURICE DE HIRSCH

See Jews: Zionism MOSES MENDELSSOHN

See Jews: Language and Literature SOLOMON J. RABINOWITZ.

See Jews: Language and Literature NIKOLA PASHITCH,

See Jugo-Slavia: 1920–1921 ALEXANDER I .

See Jugo-Slavia: 1921 DANIEL BOONE LEADING COLONISTS FOR KENTUCKY, 1773

See Kentucky: 1765-1778 KOREAN TYPES

See Korea IMAGE OF A WAR GOD

See Korea PREHISTORIC LAKE DWELLING

See Lake Dwellings RESTORATION OF THE LIBRARY AT LOUVAIN.

See Libraries: Modern: Belgium READING ROOM OF THE BRITISH MUSEUM

See Libraries: Modern: England CORRIDOR OF THE VATICAN LIBRARY

See Libraries: Modern: Italy LIBRARY OF CONGRESS, WASHINGTON .

See Libraries: Modern: United States ONE OF THE MAIN READING ROOMS OF THE NEW YORK PUBLIC LIBRARY See Libraries: Modern: United States AERIAL VIEW OF LONDON

See London CONTEMPORARY PLAN OF LONDON OF 1570

See London: 1666 EVOLUTION OF LONGBOW AND CROSSBOW.

See Longbow GENEALOGY OF LATER HOUSE OF LORRAINE .

See Lorraine THE LOUVRE MUSEUM

See Louvre

THE NEW LARNED HISTORY

FOR READY REFERENCE, READING AND RESEARCH

VOLUME VI

INVENTIONS

ANCIENT AND MEDIEVAL

tiller of the soil vied with the hunter and the

shepherd in covering man's nakedness. At first the Introduction.—"Man is sometimes distinguished wheel was driven by manual toil or by the vse as a tool-using animal. . . . (His) superiority as of beasts, but when, after many centuries, wind a tool-user . . . ultimately secured his position and water were used, man saw opening up a wider over the beasts of the world and enabled him to vista which promised speed of production and construct our material civilization. .. . His first more leisure to him who could harness the natural tool might have been a stone. A peaceful use elements to his service. Was there joy when the of stones as agricultural tools may or may not first wheel turned in the wind, or a mad claphave preceded their use as weapons. . . . Later ping of hands when one of these rough contrivances some man may have broken a stone by throwing first creaked beneath the force of a mountain it against a rock, hoping to find among the pieces stream?-We shall never know. [The time is too one suited to his needs (for digging, etc.). In far back to permit of anything beyond imaginasome such way there developed the idea of using tion upon the subject.]”—E. Cressy, Discoveries tools and of forming them. Of course, it is only and inventions of the twentieth century, pp. 1-2. a small step from breaking the stone as just Measurements: Time and space.—"The measdescribed and chipping off edges of the selected urement of small portions of time was a very stone so as to form it more nearly to the de- practical problem from the beginning. The first sired shape. But this step may not have been attempt to solve the problem consisted in obtaken for centuries. . . . Between the discovery of serving shadows cast by the sun. The changing the method of conserving fire and its production shadow of the human form was doubtless the by a simple machine many thousands of years first clock. ... Observations of this kind led to must have intervened. A primitive method is that the shadow clock or sun-dial. . . . Sun-dials have of rubbing a sharp stick back and forth in a groove been used from the beginning of time and they cut in a block of wood. . . . This simple device have not yet passed out of use. They may still is not, however, a machine. It is merely a special be seen in a few public places, but they are retool for rubbing and a block to be rubbed. When tained rather as curiosities than as real timeprimitive man arranged a combination where the keepers. For the sun-dial is not a good timekeeper rubbing tool was actuated by another part of the for three reasons: (1) it will not tell the time device, which part in turn was controlled by the at night; (2) it fails in the daytime when the operator, then he had a machine. . . . [This] is sun is not shining; (3) it can never be used inside of course a development of an earlier form .. of a house. The sun-dial can hardly be called an where a pointed stick or drill is twisted by the invention; it is rather an observation. There were, operator's hands. . . . From this primitive design however, inventions for measuring time in the we can obtain a concept of a machine as a device earliest period of man's history. Among the oldin which a motion communicated to one part est of these was the fire-clock, which measured results in a different motion of a second part."- time by the burning away of a stick or a candle. J. Mills, Realities of modern science, pp. 1, 4-8.- The Pacific islanders still use a clock of this kind. "Probably one of the most important steps ever 'On the midrib of the long palm-leaf they skewer taken by primitive man in his unconscious efforts a number of the oily nuts of a candle-nut-tree and to escape from savagery was the discovery of the light the upper one. As the nuts burn off, one wheel. The fact that rolling produced less friction after another, they mark the passage of equal porthan sliding was but dimly recognised: the me- tions of time. . . . Fire-clocks of one kind or anchanical principle involved was perhaps but vaguely other have been used among primitive people in distinguished, : . . [but the fact must soon have nearly all parts of the globe, and their use has been grasped] that here was a contrivance that continued far into civilized times. Alfred the would facilitate locomotion and increase man's Great (900) is said to have measured time in the power over his surroundings. . . . This fortunate following way: 'He procured as much wax as discoverer, together with him who first produced weighed seventy-two pennyweights, which he fire, were the forerunners of the engineers and commanded to be made into six candles, each manufacturers, the scientific discoverers and in- twelve inches in length with the divisions of ventors of to-day. The wheel made it easy to inches distinctly marked upon it. These being move huge weights and to cover great distances, lighted one after another, regularly burnt four and when it was applied to spinning it trans- hours each, at the rate of an inch for every twenty ferred part of the burden of providing clothing minutes. Thus the six candles lasted twenty-four from the animal to the vegetable kingdom. Rude hours.' ... If we could step on board a Malay skins gave place to finely woven fabrics, and the proa we should see floating in a bucket of water a cocoanut shell having a small perforation through a copper bowl. At the moment the sinking occurs which the water by slow degrees finds its way the attendant announces the hour by striking upon into the interior. This orifice is so perforated the bowl. The second step in the development that the shell will fill and sink in an hour, when of the water-clock was made in China several the man on watch calls the time and sets it to thousand years ago. In the earlier Chinese clock

the water, instead of finding its way into the vessel from the outside, was placed inside and allowed to trickle out through a hole in the bottom and fall into a vessel below. In the lower vessel was a float which rose with the water. To the float was attached an indicator which pointed out the hours as the water rose. By this arrangement, when the upper vessel was full, the water, by reason of greater pressure, ran out faster at first than at any other time. The indicator, therefore, at first rose faster than it ought, and after a while did not rise as fast as it ought to. After centuries of experience with the twovessel arrangement, a third vessel was [placed above so that) ... as fast as water flowed from the middle vessel it was replaced by a stream flowing from the one above it ... and the water flowed into the lowest vessel at a uniform rate. Finally a fourth vessel was brought into use. The Chinese water-clock has been running in the city of Canton for ... six hundred years. Every afternoon at five, since 1321, the lowest jar has been emptied into the uppermost one and the clock thus wound up for another day. To follow the further development of the water-clock we must pass from China to Greece. In their early history the Greeks had nothing better than the sun-dial with which to measure time. About the middle of the fifth century B.C. there arose at Athens a need for a better timepiece (for use in the public assembly and in the courts of law). ... The sun-dial would not answer, for the sun did not always shine, even in sunny Greece; so the idea of the water-clock was borrowed. A certain amount of water was placed in an amphora (urn), in the bottom of which was a small hole through which the water might slowly flow. When the amphora was empty the speaker had to stop talking. The Greeks called the water-clock a clepsydra, which means 'the water steals away.' The orator whose time was limited by a certain amount of water would keep his eye on the clepsydra, just as a speaker in our time keeps his eye on the clock. . . . At first the Greeks used a simple form of the clepsydra, but they gradually adopted the improvements made by the Chinese, and finally added others. The great Plato is said to have turned his attention to commonplace things long enough to invent a clepsydra that would announce the hour by playing the flute. However this may have been, there was in use in the Greek world, about 300 B.C., a clepsydra something like

a clock. As the water drops into the cylinder E the float F rises and turns G, which carries the hour hand around. Inside of the funnel A is a cone B which can be raised or lowered by the bar D. In this way the dropping of the water is regulated. Water runs to the funnel through H, and when the funnel is full the superfluous water runs off through the pipe I, and thus the depth

of the water in the funnel remains the same and Brown and Dawson, Stamford, Cona.

the pressure does not change. . . . When the hand

in this old clock has indicated twelve hours it CHINESE WATER CLOCK

begins to count over again, just as it does on our (Built over 1300 years ago)

clocks to-day. . . . If we pass from Greece to

Rome, ... we find that the Romans were slow float again. This sinking cocoanut shell, the first to introduce new methods of timekeeping. The form of the water-clock, is the clock from which first public sun-dial in Rome was constructed has been developed the timepiece of to-day. With about 200 B.C. . . . The water-clock was brought it, therefore, the story of the clock really begins. into Rome a little later than the sun-dial, and In Northern India the cocoanut shell is replaced by was used as a time-check upon speakers in and

[graphic]

and

the law courts, just as it had been in Athens. of water regulated the descent of the weight; in De When the Romans first began to

use the

Vick's clock the trickling of power or force from clepsydra it was already a very good clock. the escapement regulated the descent of the weight. Whether it received any great improvements at

The invention of this escapement is the greatest their hands is not certain. Improvements must event in the history of the clock. De Vick's inven.. bave been made somewhere, for early in the Middle tion led rapidly to the excellent timepieces of toAges we find clepsydras in forms more highly de- day, to both our watches and our clocks. After veloped than they were in ancient times. In the the appearance of the weight-clock, the waterninth century the Emperor Charlemagne received clock gradually fell into disuse, and all the ingenuias gist from the King of Persia a most interesting ty of the clockmaker was bestowed upon weights timepiece which was worked by water. "The dial and wheels and escapements and balances. A was composed of twelve small doors which repre- century of experimenting resulted in a clock withsented the divisions of the hours; each door opened out a weight. In this timekeeper is recognized at the hour it was intended to represent, and out the beginnings of the modern watch. The uncoilof it came the same number of little balls, which ing of a spring drove the machinery. Instead of fell, one by one at equal distances of time, on a the balancing beam with its weights as in De brass drum. It might be told by the eye what

Vick's clock, a balance wheel is used. The escapehour it was by the number of doors that were ment is the same as in the first weight-clock. open; and by the ear by the number of balls that The busy and delicately-hung little balance wheel fell. When it was twelve o'clock, twelve horsemen in miniature issued forth at the same time, and, marching round the dial, shut all the doors. Less wonderful than the clock of the emperor, but more useful, as an object of study, is the medieval clepsydra. This looks more than ever like the clock we are accustomed to see. It has weights as well as wheels. As the float rises with the water it allows the weight to descend and turns the spindle on the end of which is the hand which

D marks the hours. This is partly a water-clock and partly a weight-clock. The weight in its descent turns the spindle; the water regulates the rate at which the weight may descend.

H "The water-clock just described led easily and directly to the weight-clock. Clockmakers in the Middle Ages for centuries tried with more or less success to make clocks that would run by means I of weights. In 1370, Henry De Vick, a German, succeeded in solving the problem. De Vick was brought to Paris to make a clock for the tower of the king's palace, and he made one that has become famous. In a somewhat improved form it can still be seen in Paris in the Palais de Justice. Let us remove the face of this celebrated timepiece and take a look at its works. It had a striking part, and a timekeeping part, each distinct from the other. . . . The weight, of 500 pounds, is wound up by a crank (the key). [There is also an] .: . hour hand. [If the weight] is allowed to descend, it is easily seen how the whole system of wheels will be moved-and that very rapidly. But if something does not prevent, ... [the weight) will descend faster and

IMPROVED GREEK CLEPSYDRA saster, the hour-hand will run faster and faster and the clock will run down at once. If the clock is in your watch is a growth from De Vick's clumsy to run at a uniform rate and for any length of balance beam. The spring-clock would run in any time, the power of the weight must escape grad. position. Because it could be carried about it led ually. In the clepsydra the descent of the weight almost at once to the watch. Many places claim was controlled by the size of the stream of flowing the distinction of having made the first watch, but water. De Vick invented a substitute for the stream

seems that the honor belongs to the city of Nuremof flowing water. . . . Fixed to the upper part of berg. - 'Nuremberg eggs,' as the first portable the (post) ... is a beam or balance, at the ends clocks were called were made as early as 1470. The of which are two small weights, and projecting first watches were large, uncouth affairs, resembling from the posts in different directions are two small table clocks but by the end of the sixteenth pallets or lips. Now, as the top of the wheel century small watches with works of brass and turns toward you, one of its teeth catches the cases of gold or silver were manufactured."pallet and turns the post a part of the way round S. E. Forman, Stories of useful inventions, PP. 188toward you. Just as the tooth escapes a tooth 200. at the bottom of ... (the wheel] (moving from For space measurement, "the oldest known stanyou) catches the pallet and checks the revolving post dard of length, the cubit, was the distance between and turns it from you. Thus as (the wheel] . the point of a man's elbow and the tip of his turns, it gives a to-and-fro motion to the post and, middle finger. In Egypt the ordinary cubit was consequently, a to-and-fro motion to the balance. 18.24 inches, and the royal cubit, 20.67 inches. A ... (The wheel) is called the escapement because royal cubit' in hard wood, perfectly preserved, the power of the descending weight gradually es- was discovered among the ruins of Memphis early capes from its teeth. In the clepsydra the trickling in the nineteenth century. It bears the date of the

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