The Wonder Book Of Knowledge - BestLightNovel.com
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[Ill.u.s.tration: RAW STOCK ROLLS, KODAK PARK]
[Ill.u.s.tration: a.s.sEMBLING ROOM, CAMERA WORKS]
To lighten the camera burden, and to simplify the various photographic processes, were the problems that confronted the American inventor. The first step toward film photography--and it was film photography that relegated camera bulk to the sc.r.a.p heap--was a roll film made of coated paper to which a sensitive emulsion was applied, but the real goal was reached when cellulose was subst.i.tuted as a film base. This made practicable the present flexible, transparent film with its attendant convenience and dependability.
The kodak was the natural outcome of the roll film system. The first one appeared in 1888, and its development, which proceeded simultaneously with the film discoveries, soon reached the point where the loading and unloading could be done in daylight. Daylight developing soon followed, and the dark room, as far as the kodaker was concerned, took its proper place as a relic of the dark ages.
With 1914 came autographic photography, so that now with a kodak in one pocket and a handful of film in the other, the amateur is equipped for a picture-making tour of the world--not simply a pictorial record, but a written record as well, for autographic photography permits the dating and t.i.tling of each negative directly after exposure.
Photography, not so many years ago an exclusive pleasure for the few, is now easy fun for millions.
[Ill.u.s.tration: FILTER ROOM, KODAK PARK
Cellulose Acetate Manufacturing]
How Deep is the Deepest Part of the Ocean?
Man has not been able to tell definitely just what the greatest depth of the ocean is, because it would be a practically unending task to go over every bit of it to take measurements. A great many exploring expeditions have been sent out to determine that interesting information so far as possible, however, and one of these, the Murray-Challenger expedition, has reported that the greatest depth that could be found in the Atlantic Ocean is 27,366 feet, in the Pacific Ocean 30,000 feet, in the Indian Ocean 18,582 feet, in the Southern Ocean 25,200 feet and in the Arctic Ocean 9,000 feet. They also stated that the Atlantic Ocean has an area in square miles, of 24,536,000; the Pacific Ocean, 50,309,000; the Indian Ocean, 17,084,000; the Southern Ocean, 30,592,000 and the Arctic Ocean, 4,781,000.
Why do We Say "Get the Sack"?
The use of the expression "get the sack," when we mean "to be discharged," originated through the impression made upon people in this country when stories were brought to them of the way the Sultan of Turkey disposed of members of his harem of whom he had tired. When he wanted to get rid of one of his harem he was said to have had her put into a sack and thrown into the Bosporus. People who heard of this report repeated it to others and they became so used to telling the tale that they slipped quite naturally into the habit of saying "to get the sack" when they meant that they expected to be put out of a position suddenly.
In very much the same way the phrase "Hobson's choice" is supposed to have resulted from the story told here of a livery-stable keeper at Cambridge, England, called Hobson, who obliged each customer to take the horse nearest the stable door, when a wish to hire one was expressed, even though he might permit customers to make the rounds of all the stalls, examining and perhaps selecting other horses. Since the interest inspired by that report, "Hobson's choice" has come to mean a choice without any alternative, or the chance to take the thing which is offered or nothing.
Why do We Call Them X-Rays?
At the time the discovery of X-rays was announced by Prof. Wilhelm Conrad Rontgen of the University of Wurzburg, Germany, he was not sure of their exact nature, and so he named them "X-Rays," because "X" has always been understood to be the symbol for an "unknown quant.i.ty."
They are invisible rays transmitted through the air in a manner similar to light. They are produced by pa.s.sing unidirectional electric current of from twenty to one hundred thousand volts pressure through a specially constructed high vacuum tube, within which rays radiating from the surface of a concave cathode (the negative electrode of a galvanic battery), are focused upon and bombard a target of refractory material such as tungsten, iridium, platinum, from which focus spot the X-rays radiate in all directions.
They are used in medicine and surgery, to photograph the skeleton and all the internal organs of the human body, as an aid in diagnosis; also to destroy diseased tissue without the aid of surgery. Cancers and tumors of certain kinds and a number of skin diseases are said to be made to disappear by their use. When the apparatus is used, the subject is placed on a long table and the X-ray tube, in its lead gla.s.s s.h.i.+eld container, is brought over the part of the body to which the rays are to be applied.
The most up-to-date apparatus consists of a high-tension transformer and rectifier, driven by a rotary converter, which derives power from direct-current electric service and delivers alternating current to the high-tension transformer.
[Ill.u.s.tration: MODERN X-RAY APPARATUS]
How did the Term "Yankee" Originate?
Although some people maintain that the word "Yankee" originated with the way white men interpreted the Indians' name for the early settlers, most of those who have wondered about it have decided that it came to be used as a nickname for persons born in the United States, because of a farmer, named Jonathan Hastings and living in Cambridge, Ma.s.sachusetts, in the eighteenth century, using it to describe some good, home-made cider of his making, as "Yankee cider." The word was taken up by the students of Harvard University, and gradually spread throughout the whole country.
Why do We Say "Kick the Bucket"?
A great many years ago a man called Bolsover became crazed by some unhappy experiences and decided to kill himself by fastening a rope around his neck and hanging from a cross-beam overhead. In selecting a place to tie the rope high enough to accomplish his purpose he found that he would have to stand on something in order to reach it, and so he reached for the nearest thing, which happened to be a bucket; after the rope was firmly adjusted he kicked the bucket out from under his feet and his full weight hung suspended from the rope about his neck. The publicity given his act resulted in the adoption of the phrase "to kick the bucket" as meaning "to die," and that is the explanation which most people who have tried to look up the origination of the term give as its first use.
When does a Tortoise Move Quickly?
Tortoises lay their eggs in underground nests, where they remain for almost a year, and, strange to say, they have a very curious way of drilling holes for these nests with their tails. A tortoise picks a spot where the earth is bare, and then stiffens its tail by contracting the muscles strongly, placing the tip firmly against the ground and boring a hole by moving it round and round in a circle, until a cone-shaped cavity is produced, wide at the top but tapering to a point below. When this operation is completed, it immediately sets to work to enlarge the hole with the help of its hind legs. It does this by scooping out "shovelfuls" of dirt, first with one of its hind feet and then with the other, and heaping it up like the wall of a fortress around the pit.
Tortoises use their feet like hands when they do this, very carefully placing the dirt in a circle at some little distance from the edge of the cavity, and the work is continued until the hole is dug down as deep as the hind legs will reach. When it finds that no more soil can be removed, that is, at the end of an hour or more of steady digging, the tortoise accepts the job as completed and proceeds to deposit its eggs inside very carefully, just as you would put hen's eggs into a basket.
While all this is going on the body is scarcely moved and the head is kept inside the sh.e.l.l.
There are usually nine eggs and they just about fill the bottom of the nest, which measures approximately five inches across and is itself shaped more or less like an egg, being wider inside than at the top.
After about half an hour's rest, the hardest part of the work is begun--that of filling up the hole and leveling the ground. The dirt is placed carefully over the eggs, a "handful" at a time, the hind legs being used alternately again for that purpose. As the cavity is gradually filled up the tortoise presses the earth down with the outer edge of its foot. It takes another half hour's rest after all the dirt has been carried back again, and then commences the part of the operation where the tortoise moves quickly enough to merit another racing t.i.tle. It beats down the dirt-mound and stamps it firm and flat with the under side of its hard sh.e.l.l, raising the hind end of its body and then hurriedly letting it drop to the ground again, turning round and round in a circle very briskly in the meantime, at the same time doing all it can to remove any traces which might lead to the discovery of its nest.
The Story in a Newspaper[11]
Among the marvels of machinery of the present day there are none more complicated and bewildering in appearance than that by which the news of the world is sent adrift within the daily newspaper and none more marvelously effective in its operation. If we go back to the days when the seeds of the modern press were planted, we find them in the hand-printing done by the Chinese with their engraved blocks, and with the simple press used by Gutenberg about 1450, when he printed the first book from movable types.
His press consisted of two upright timbers held together by cross pieces at top and bottom. The flat bed on which the types rested was held up by other cross timbers, while through another pa.s.sed a wooden screw, by the aid of which the wooden "platen" was forced down upon the types. The "form" of type was inked by a ball of leather stuffed with wool, the printer then spread the paper over it, laying a piece of blanket upon the paper to soften the impression, after which the screw forced the platen down on the paper and this on the type. This press was not original, since similar cheese and linen presses were then in use.
[Ill.u.s.tration: THE BLAEW PRESS, 1620]
For 150 years this crude method of printing continued in operation, the first known improvement being made by an Amsterdam printer about 1620, he adding a few parts to render the work more effective. Such was the simple press still employed when Benjamin Franklin began his work as a printer a century later. In 1798 the Earl of Stanhope had a cast-iron frame made to replace the wooden one and added levers to give more power to the pressman. Woodcuts were then being printed and needed a stronger press.
We must go on with the old Gutenberg method and its tardy improvements, for another century, or until about 1816, when George Clymer, a printer of Philadelphia, did away with the screw and employed a long and heavy cast-iron lever, by the aid of which the platen was forced down upon the type, the operation being a.s.sisted by accompanying devices.
As will be seen, the growth of improvements had until then been very slow. From this time forward it became far more rapid, some useful addition to the press being made at frequent intervals. The "Was.h.i.+ngton"
press, used at this time by R. H. Hoe & Co., of New York, embodied these improvements, and became one of the best hand-printing presses so far made. The first steam-power press was introduced by Daniel Treadwell, of Boston, in 1822, the bed and platen, or its successor, the cylinder, being used in these and in the improved forms that followed until after the middle of the century.
[Ill.u.s.tration: STANHOPE PRESS, 1798]
The idea of replacing the platen by a cylinder was not a new one. It was employed in printing copper-plate engravings in the fifteenth century, a stationary wooden roller being employed, beneath which the bed, with its form and paper, was moved backward and forward, a sheet being printed at each movement. With this idea began a new era in the evolution of the printing press. A vast number of patents have since been issued for printing machines in which the cylinder is connected with the bed and later for the operation of two cylinders together, one holding the form of type and the other making the impression. But all these were for improvements, the underlying principle remaining the same. The conception of a press of this character in which the paper was to be fed into the press in an endless roll or "web" goes back to the beginning of the nineteenth century, though it was not made available until a later date.
[Ill.u.s.tration: CLYMER'S COLUMBIAN PRESS, 1816]
Meanwhile, however, patent after patent for the improvement of the cylinder press were taken out and the art of printing improved rapidly, the firm of Hoe & Co. being one of the most active engaged in this business, the United States continuing in advance of Europe in the development of the art. The single small cylinder and double small cylinder introduced by this firm proved highly efficient, the output of the former reaching 2,000 impressions per hour, while the double type, used where more rapid work was needed, yielded 4,000 per hour.
[Ill.u.s.tration: PETER SMITH HAND PRESS, 1822]
But the demands of the newspaper world steadily grew and in 1846 a press known as the Hoe Type Revolving Machine was completed and placed in the office of the _Public Ledger_, of Philadelphia. By increasing the number of cylinders the product was rapidly added to, each cylinder printing on one side 2,000 sheets per hour.
In 1835 Sir Rowland Hill suggested that a machine might be made that would print both sides of the sheet from a roll of paper in one operation. A similar double process had been performed for many years in the printing of cotton cloth. This remained, however, a mere suggestion until many years later, and the one-side printing continued. But, by adding to the number of cylinders, a speed of 20,000 papers thus printed was in time reached.
[Ill.u.s.tration: TREADWELL'S WOODEN-FRAME BED AND PLATEN POWER PRESS, 1822]
To prevent the possible fall of types from a horizontal cylinder, the vertical cylinder was introduced by the London _Times_, but this danger was overcome in the Hoe presses, and by the subsequent invention of casting stereotype plates in a curve the final stage of perfection in design was reached. In 1865 William Bullock, of Philadelphia, constructed the first printing press capable of printing from a web or continuous roll of paper, knives being added to cut the sheets, which were then carried through the press by tapes or fingers and delivered by the aid of metal nippers. There were difficulties in this series of operations, but these were overcome in the later Hoe press, in which the sheets were merely perforated by the cutter, and were afterward fully separated by the pull of accelerating tapes.