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HOROLOGY AND INSTRUMENTS OF PRECISION. · Inventions of the Century

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  Section twenty six of Inventions in the Century. This is a LibriVox recording.
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  All LibriVox recordings are in the public domain. For more information ought to volunteer,
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  please visit liprivox dot org. Recording by Avay in November two thousand,
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  twenty three. Inventions in the Century by William Henry Doolittle, Chapter twenty five,
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  Horology and Instruments of precision. Time measures all things, but I measure
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  it so far as we at present know. There were four forms of time
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  measuring instruments known to antiquity, the sun dial, the klepsidra or water clock,
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  the hour glass, and the graduated candle. The sun dial, by
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  which time was measured by the shadow cast from a pin rod or pillar upon
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  a graduated horizontal plate. The gradations, consisting of twelve equal parts in which
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  the hours of the day were divided, were both as to the instrument and
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  the division of the day into hours, invented by the Babylonians or other Oriental
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  race set upon the plains of Chaldaea, constructed by the Chinese and Hindus,
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  put into various forms by these nations, and adapted but unimproved by the learned
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  Greeks and conquering Romance. It appears to have been unknown to the Assyrians and
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  Egyptians, or if known, its knowledge confined to their wise men, as
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  it does not appear on any of their monuments. The klepsidra an instrument by
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  which, in its earliest form, a portion of time was measured by the
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  escape of water from a small orifice in the bottom of a shell or vase,
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  or by which the empty vase placed in another vessel filled with water was
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  gradually filled through the orifice, and which sank within a certain time, is
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  supposed by many to have preceded the invention of the sun dial. At any
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  rate, they were used contemporaneously by the same peoples. In its later form,
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  when the day and night were each divided into twelve hours, the vessel
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  was correspondingly graduated, and a float raised by the inflowing water impelled a pointer
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  attached to the float against the graduations. Plato, it is said, contrived
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  a bell so connected with the pointer that it was struck at each hour of
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  the night. But the best of ancient klepsidras was invented by Stasibius of Alexandria
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  about the middle of the third century BC. He was the pupil of Archimedes,
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  and adopting his master's idea of geared wheels, he mounted a toothed wheel
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  on a shaft extending through the vessel and carrying at one and outside of the
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  vessel a pointer adapted to move around the face of a dial graduated with the
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  twenty four hours. The vertical too trod or rack adapted to be raised or
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  lowered by a float in a vessel gradually filled with water, engaged a pinion
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  fixed on another horizontal shaft, which pinion in turn engaged the larger wheel.
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  It was not difficult to proportion the parts and control the supply of water to
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  make the point complete its circuit regularly. Then the same inventor dispensed with the
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  wheel, rack and pinion and substituted a cord to which a float was attached,
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  passing the cord over a grooved pulley and securing a weight at its other
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  end. The pulley was fixed on the shaft which carried the hour hand.
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  The float was a counterbalance to the weight, and as it was lifted by
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  the water, the weight stretched a cord and turned the which caused the pointer
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  to move on the tile and indicate the hour. The water thus acted as
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  an escapement to control the motive power. In one form, the water dropped
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  on wheels which had their motion communicated to a small statue that gradually rose and
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  pointed with a rod to the hour upon the tile. Thus, the essential
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  parts of a clock an escapement, which is a device to control the power
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  in a clock or watch so that it shall act intermittently on the time index,
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  a motive power, which was then water or a weight. A dial
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  to display the hours, and an index to point them out were invented at
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  this early age, but the art advanced practically no further for many centuries.
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  The hour glass is too familiar to need description. The incense sticks of the
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  Chinese, the combustion of which proceeded so slow and regularly as to render them
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  available for time measures, were the precursors of the graduated candles. With the
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  ungraduated sundial, the Greeks fixed their times for bathing and eating. When the
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  shadow was six feet long, it was time to bathe, When twice at
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  length it was time to sup The clepsidra became in grease a useful instrument to
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  enforce the law in restricting loquacious orators and lawyers to reasonable limits in their addresses.
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  And in Rome, the sun dials, the klepsidras, and the hour
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  glass were used for the same purpose, and more generally than in Greece,
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  to regulate the hours of business and pleasure. The graduated candles are chiefly notable
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  as to their use, if not invention, by Alfred the Great in about
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  eight hundred eighty three. They were twelve inches long, divided into twelve parts,
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  of which three would burn in one hour. In use, they were
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  shielded from the wind by thin pieces of horn, and thus the horn lantern
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  originated with them. He divided the day into three equal parts, one for
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  religion, one for public affairs, and one for rest and recreation. Useful
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  clocks of wondrous make were described in the annals of the Middle Ages, especially
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  in Germany, made by monks and others for kings, monasteries, and churches.
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  The Old Saxon and Teutonic words kliger and goloce, signifying the striking of
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  a bell, and from which the name clock is derived, indicates the early
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  combination of striking and time keeping mechanism. The records are scant as to the
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  particulars of inventions in horology during the Middle Ages and down to the sixteenth century.
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  But we know that weights and trains of wheels and springs, and some
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  say pendulums, were used in clockwork, and that the tones of hourly bells
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  floated forth from the dim religious light of old cathedrals. They all appear to
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  have involved, in different forms, the principle of the old klepsidra, using
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  either weights or water as the motive power to drive a set of wheels and
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  to move a pointer over the face of a dial. Henry de Vick of
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  France about thirteen seventy constructed a celebrated clock for Charles the Fifth, the first
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  nearest approach to modern weight clocks. The weight was used to unwind a cord
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  from a barrel. The barrel was connected to a ratchet, and there were
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  combined therewith a train of toothed wheels and pinions, an escapement consisting of a
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  crown wheel controlled by two pallets, which in turn were operated alternately by two
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  weights on a balanced draft. An hour hand was care rate bioshaft of the
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  great wheel, and a dial plate divided into hours. This was a great
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  advance, as a more accurate division of time was had by improving the isochronous
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  properties of the vibrating escapement, But the world was still wanting a timekeeper to
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  record smaller portions of the day than the hour, and a more accurate machine
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  than VIX. Two hundred years nearly elapsed before the next important advance in horology.
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  By this time, great astronomers like Tihoprahe and Valerius had divided the time
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  recording dials into minutes and seconds. About fifteen twenty five, Jacobzech of Prague
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  invented the fuze, which was reinvented and improved by the celebrated doctor Hook one
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  hundred twenty five years later, small portable clocks, the progenitors of the modern
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  watch, commenced to about fifteen hundred. It was then that Peter Heele of
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  Nuremberg substituted for weights as the motive power a ribbon of steel, which he
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  wound around a central spindle, connecting one end to a train of wheels,
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  to which it gave motion as it unwound. Then followed the famous observation of
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  the swinging lamp by the then young Galileo about fifteen eighty two while lounging in
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  the Cathedral of Pisa. The isochronism of the vibrations of the pendulum inferred from
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  this observation was not published or put to practical application in clocks for nearly sixty
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  years afterwards. In sixteen thirty nine, Galileo, then old and blind,
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  dictated to his son one of his books in which he discussed the isochronal properties
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  of oscillating bodies and their adaptation as time measures. He and others had used
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  a pendulum for dividing time time, but moved it by hand and counted its
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  vibrations. But Hugens, the great Dutch scientist about fifteen fifty six, was
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  the first to explain the principles and properties of the pendulum as a time measurer
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  and to apply it most successfully to clocks. His application of it was to
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  the old clock of Vics. The seventeenth century thus opened up a new era
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  in clock and watchmaking. The investigations, discoveries and inventions of Hugens and other
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  Dutch clockmakers, of doctor Hook and David Ramsey of England, Holt Furlu of
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  France, and a few others placed the art of clock and watchmaking on the
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  scientific basis on which it has ever since rested. The pendulum and watchsprings needed
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  to have their movements controlled and balanced by better escapements. Hugens thought that the
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  pendulum should be long and swing in a cycloidal course, but doctor Hook found
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  the better way to produce perfect isochronous movements was to cause the pendulum to swing
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  in short arcs, which he accomplished by his invention of the anchor escapement.
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  The fuzi, which doctor Hook reinvented, consists of a conical, spirally grooved
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  pulley around which a chain is wound, and which is connected at one end
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  to a barrel in which the main actuating spring is tightly coiled. The fuze
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  is thus interposed between the wheel train and the spring to equalize the power of
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  the latter. To doctor Hook must also be credited the invention of that delicate
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  but efficient device, the hair spring balance for watches. His inventions in this
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  line were directed to the best means of utilizing and controlling the force of springs,
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  his motto being uttensio sik vis as the tension is is the force repeating
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  watches to strike the hours, half hours, and quarters made their appearance in
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  the seventeenth century. In the next century, Arnold made one for George,
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  the third as small as in English sixpence. This repeated the hours, halves,
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  and quarters, and in it for the first time in the art,
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  a jewel was used as a bearing for the arbors, and this particular one
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  was a ruby made into a minute cylinder. After the discovery and practical application
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  of weights, springs, wheels, livers, and escapements to time mechanisms,
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  subsequent inventions, numerous as they have been, have consisted chiefly not in the
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  discovery of new principles, but in new methods in the application of old ones.
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  Prior to the eighteenth century, however, clocks were cumbrous and expensive,
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  and the watches rightly regarded as costly toys, and as to their accuracy in
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  time measuring, the cheaper ones were hardly as satisfactory as the ancient sun dials.
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  With the coming of the machine inventions and the new industrial and social ideas
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  of the eighteenth century came an almost sudden new appreciation of the value of time.
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  Hours, minutes, and seconds began to be carefully prized both by the
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  trades and professions, and the demand from the common people for accurate time records
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  became great this demand. It has been the office of the nineteenth century to
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  supply and to place clocks and watches within the reach of the poor as well
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  as the rich. While thus lessening the cost of time keepers, their value
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  has been enhanced by increasing their accuracy and durability. Among the other ideas for
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  which the eighteenth century was famous in watchmaking was that of this spencing with the
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  key for winding, thus saving the losing of keys and preventing axis of dust,
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  an idea which however, was perfected only in the last half of the
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  nineteenth century. The eighteenth century was chiefly distinguished by its scientific improvements in timekeepers
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  to adapt them for astronomical observations and for use at sea. In not only
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  accurately determining the time, but the degrees of longitude. Chronometers were invented,
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  distinguished from watches and clocks by means by which the fluctuation of the parts caused
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  by the variations in temperature are obviated or compensated in clocks. What are known
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  as the mercurial and gridiron pendulums were invented respectively toward the close of the eighteenth
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  century by Graham and Harrison, and the latter also subsequently invented the expanding and
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  contracting balance wheel for water. The principle in these appliances is the employment of
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  two different metals which expand unequally and thus maintain a uniformity of operation. The
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  Dutch, with Huygens in the lead, were long among the leading clockmakers.
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  Germany ranked next. It was in the seventeenth century that a wonderful industry in
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  clockmaking there commenced, which lasted for two centuries. The Black Forest region of
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  South Germany became a famous locality for the manufacture of cheap wooden clocks. The
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  system adopted was a minute division of labor. From fourteen to twenty thousand hands
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  twenty years ago were employed in the Schwarswalds district. Labor saving machines were ignored
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  almost entirely. The annual production finally reached nearly two million clocks of the value
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  of about five million dollars. Switzerland, in what making, followed precisely the
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  example of Germany in clockmaking. It commenced there in the seventeenth and culminated in
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  the nineteenth century. Many thousands of its population were engaged in the business,
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  and it flourished under the fostering care of the government by the establishment of astronomical
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  observations for testing, the adjustment of the best watches, the giving of prizes,
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  and the establishment and encouragement of schools of horology conducted on thorough scientific methods.
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  A quarter of a century ago, it was estimated that in Switzerland forty
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  thousand persons out of a population of one hundred fifty thousand were engaged in watchmaking,
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  and that the annual production sometimes reached one million, six hundred thousand completed
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  movements. The whole world was their market. The United States alone was in
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  eighteen seventy five importing one hundred thirty four thousand watches annually from that country.
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  As in Germany, so one characteristic of the Swiss system was a minute subdivision
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  of the labour. Individuals and entire families had certain parts only to make.
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  It is said that the Swiss watch passed through the hands of one hundred and
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  thirty different workmen before it was put upon the market. The use of machines
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  was also, as in Germany, ignored by this national devotion to a single
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  trade and its subdivision of labour. The successful production of complicated watches became great
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  and their prices comparatively low. The United States, in the commencement of its
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  career, and at the opening of the century, had no clocks or watches
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  of its own manufacture. But it soon followed the example of Germany in Switzerland
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  and established cheap clock manufactories, first of wood and then of metal, which
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  became famous and of worldwide use. But it could make no headway against the
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  cheap labor of Europe in watchmaking, and the country was flooded with watches of
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  all qualities, principally from Switzerland and England. Finally, at the half way
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  mark in the century, the inquiry arose among Americans why could not the system
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  of the minute subdivision of human labor followed in watchmaking countries so cheaply and profitably
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  be accomplished by machinery. The field was open, the prize was great,
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  and the government stood ready to grant exclusive patents to every inventor who would devise
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  a new and useful machine. The problem was great, as the fields abroad
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  had been filled for generations by skilled artisans who had reduced the complicated mechanism of
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  watchmaking to a fine art Fortunately, the habit had been established in America in
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  several of the leading industries, principally in that of fire arms, of fabricating
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  separate machinery for the independent making of numerous parts of the same implement, whereby
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  uniformity and interchangeability were established. Under such a practice, which was known as
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  the American system, a duplicate of the smallest part of a complicated machine lost
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  or worn out thousands of miles from the factory could soon be furnished by simply
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  sending the number one name of such required part to the manufacturer or to the
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  nearest dealer in such machines. With such encouragement and example, the scheme of
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  watchmaking was commenced. Soon large factories were built, and by the time of
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  the Centennial Exhibition in eighteen seventy six, the American Watch Company of Waltham,
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  Massachusetts, were enabled to present an exhibit of watch movements made by machinery,
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  which astonished the world. Other great companies in different parts of the country soon
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  followed. With the same time general system machines working with the apparent intelligence and
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  facility of human minds and hands, and with greater mathematical accuracy than was possible
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  with the hands appeared. For cutting out the finest teeth from black wheels stamped
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  out from steel or brass. For making and cutting the smallest, finest threaded
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  screws by the thousands per hour and with greatest uniformity and accuracy. For jewel
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  making, for cutting and polishing by diamonds or sapphire armed tools the rough unpolished
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  diamond and ruby, chrysolite, garnet or aquamarine, and for boring, finishing,
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  and setting the same. For the formation of the most delicate pins or
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  arbors. For the making of the escapements, including forks, pallets, rollers,
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  and scape wheels. For making springs and balances, including the main springs
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  and hair springs, for making in setting the stem winding parts, for making
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  the cases and engraving the same, et cetera. The list would be too
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  long to simply name all the ingenious machines the are exhibited and subsequently invented for
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  every important operation. It was the aim of these manufacturers to locate every great
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  factory in some quiet and attractive spot, free from the dust of town and
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  city, and divided into many departments, from the blacksmithing to the packing and
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  transportation of the completed article, and to conduct every department with the best mechanical
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  and mathematical skill that money and brains could provide. The same system was followed
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  with equal success in producing the first class pocket chronometer for the nicest work to
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  which chronometers can be put. Thus, with every watch and its every part
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  made the exact duplicate of its fellow, uniformity in time keeping has been established,
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  and the simidley of Pope is no longer so correct tis with our judgments
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  is our watches? None go just alike, yet each believes his own.
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  A simple statement of this system illustrates with greater force than an entire volume.
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  The revolution the nineteenth century has produced in the useful art of horology. And
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  yet the story should not omit reference to the application of the electric system to
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  clocks, whereby clocks at distant points of a city or country are connected,
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  automatically corrected, and set to standard time from a central observatory or other time
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  station. Great as were the advances in horology during the seventeenth and eighteenth centuries,
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  the number of inventions that have been made in the nineteenth century is evidenced
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  by the fact that in the United States, alone. About four thousand patents
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  have been granted since eighteen hundred, which however represent not only American inventions but
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  very many of other countries. Registering devices devices for recording fares and money have
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  employed the keenest wits of many inventors, and is an art of quite recent
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  origin. Attention was first directed to fare registers in public vehicles, the object
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  of which is to accurately report to the proper office of the company at the
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  end of a trip or of the day the number of passengers carried and the
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  fares received. Portable registers, to be carried by the conductor and operated in
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  front of the passenger, have been almost universally succeeded by stationary ones set up
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  at one end of the vehicle, in open view of all the passengers,
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  and operated by a strap and lever by the conductor. These fare registers have
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  been called a mechanical conscience for streetcar conduct. Cash registers, intended to compel
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  honesty on the part of retail salesmen, are required to be operated by them,
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  and when the proper lever or levers or it may be a crank handle,
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  is or are touched, the machine automatically records the amount of the sale,
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  the amount of change given, and the total amount of all the sales
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  and money received and paid out. Voting machines designed to overcome the difficulties,
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  expenditure of time and the commission of errors and frauds experienced in the reading and
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  counting of votes have received great attention from inventors and are not yet in a
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  satisfactory condition. The problem involves the dispensing of printing the ballots, the prevention
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  of fraudulent deposition of ballots, the automatic correct counting of the same, and
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  a display of the result as soon as the balloting is closed. Successful electrical
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  devices have been made for recording the votes of a great number of persons in
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  a large assembly by the touch of an A or nay button at the seat
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  of the voter, and the recording of the same on paper at a central
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  desk. The invention and extensive use of bicycles, automobiles, et cetera have
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  given rise to the invention of cyclometers, which are small devices connected to some
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  part of the vehicle to indicate to the rider or a driver at the rate
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  at which he is riding and the number of miles ridden. Speed indicators.
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  Many municipalities having adopted ordinances limiting the rate of speed for street and steam cars,
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  bicycles, automobiles, and other vehicles. A want was created which has
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  been met for devices to indicate to the passengers, drivers, or conductors the
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  rate at which the vehicle is traveling, and to sound an alarm in case
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  of excess of speed, so that breaks can be applied and the speed reduced,
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  or to relieve patrons of anxiety and trouble. In this respect, ingenious
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  devices have been contrived which automatically reduce the speed when the prescribed limit has been
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  exceeded. Weighing scales and machines, just balances and just weights have been required
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  from the day of the declaration. A false weight is an abomination unto the
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  Lord, and therefore strict accuracy must always be the measure of merit of a
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  weighing machine. To this standard, the inventions of the century in weighing scales
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  have come until this century. The ordinary balance with equal even arms suspended from
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  a central point and each carrying means for suspending articles to be weighed or compared
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  in weights, and a later steel yard with its unequal arms with its graduated
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  long arms, and a sliding weight and holding pan were the principal forms of
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  weighing machines. Platform scales were described in an English patent to One's Salmon in
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  seventeen ninety six, but their use is not recorded. The compound lever scale,
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  on the principle of the steel lyard, but arranged to be used with
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  a platform, was invented and came into use in the United States about eighteen
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  thirty one. Tadaeus and Erastus Fairbanks of Saint Johnsbury, Vermont were the inventors,
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  and it was found to meet the want of farmers in weighing hemp,
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  hay, et cetera by more convenient means than the ordinary steelyard. They converted
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  the steel lyard into platform scales. The leading characteristics of such machines are first
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  a convenient platform, nicely balanced on knife edges of steel levers, and second
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  a graduated horizontal beam a sliding weight to thereon, connected by an upright rod
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  at one end to the beam and at its opposite end to the balance frame
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  beneath the platform. The modification in size and adaptation of this machine for the
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  weighing of different commodities amounted to some four hundred different varieties, running from the
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  delicately constructed apparatus for weighing the fraction of a grain, to the ponderous machines
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  for weighing and recording the loaded freight car of fifty or sixty tons, or
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  the canal boat or other vessel with its load of five or six hundred tons.
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  The adaptation of a balance platform on which to place a light load or
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  to drive theiron with heavy loads, whether of horses, steam, or water
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  vehicles, was a great blessing to mankind. No wonder that they were soon
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  sold all over the world, and that monarchs and people hastened to heap honors
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  on the inventors. Spring waghing scales have recently been invented which will accurately and
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  automatically show not only the weight, but the total price of the goods weight,
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  the price per unit being known and fixed. In the weighing of large
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  masses of coarse material such as grain, coal, cotton seed, and the
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  like, machines have been constructed which automatically weigh such materials and at the same
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  time register the weight. Previous to this century, no method was known except
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  the exercise of good judgment in the light of experience of accurately testing the strength
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  of materials. Wood and metals were used in unnecessarily cumbrous forms for the purpose
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  to which they were put in order to insure safety, or else the strength
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  of the parts failed where it was most needed. The idea of testing the
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  tensile, transverse and cubical resisting strength of materials has been applied to many other
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  objects than beams and bars of wood and metals, to belts, cloths,
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  cables, wires, fibers, paper, twine, yarn, cement, and
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  to liquid Chiraldi, Kennedy and others of England, Tomusset of France, Richle
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  of Germany, and Fairbanks, Thurston and Emery of the United States are among
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  the noted inventors of such machines. In the Emery system of machines consisting of
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  scales, gauges, and dynamometers, the power exerted on the material tested is
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  transmitted from the load to an indicating device by means of liquid acting on diaphragms.
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  The same principle is employed in his weighing machines. By one of these
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  hydraulic testing machines, the tensile strength of forged links has been ascertained by the
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  exertion of a power amounting to over seven hundred thousand pounds bgel for breaking a
• 31:00
  link. The chain breaking with a loud report. The most delicate materials are
• 31:06
  tested by the same machine the tensile strength of a horse here, some of
• 31:11
  which are found to stand the strain of one and two pounds. Eggs and
• 31:15
  nuts are cracked without being crushed, and a power exerted and a strain endured.
• 31:21
  Automatically recorded steel beams and rods have been subjected to a strain of a
• 31:26
  million pounds before breaking. Governments, municipalities, and the people generally are thus
• 31:33
  provided with means by which they can proceed with the greatest confidence in the safe
• 31:40
  and economical construction and completion of their buildings and public works. End of Section twenty six