• History of rubber

    "It has a significant healing effect: it strengthens the stomach, stops vomiting, stimulates appetite and cleanses the blood;promotes blood circulation, has a beneficial effect on the lungs, gives relief from coughing, softens the pain in the side and reduces the suffering of the sick with tuberculosis;weakens the toothache and strengthens the gums, sore from scurvy. "Try, after reading a passage from an ancient medical treatise, to guess what kind of medicine it is. And do not try - you will not guess. Because it's not medicine at all, but. .. rubber. He was credited with healing properties, which he did not possess, but about other, more important qualities, strangely enough, people learned after they started using this material.

    When Christopher Columbus brought several pieces of an unknown substance to his homeland at the end of the 15th century, it did not attract the attention of compatriots: their heads were occupied with thoughts of other treasures of newly discovered lands - gold, silver, spi

    ces - in a word, that in those dayswas considered a true value. Moreover, nobody knew about the origin of the curious souvenir. True, there were "eyewitnesses" who claimed that it was excrement of a fantastic animal. The fact that this resin, obtained by local residents from the bark of trees, hardened in the air and called "caoutchouc", was found out much later. And contemporaries of Columbus, in fact, rejected rubber, when he appeared in Europe for the first time.

    Columbus accepts the gifts of the Indians.

    It's been almost 250 years. The meeting was attended by the Paris Academy of Sciences. Listened to the report of Charles Marie de la Condamine on the journey to South America. But instead of a serious report, a scientist with an indecent impulse for such an important and representative institution began to show an inconspicuous ball of incomprehensible origin and invited them to admire: "Look, gentlemen, worthy members of the Academy! Look closely! This little ball is more wonderful than the stones of all the alchemists of the world taken together! He is able to take thousands of species, he can appear in thousands of different forms, he is called upon even to drain the tears of people, bringing with him genuine happiness for humanity. "The opinion of the honorable members of the academy was unanimous: "Fantaser!" So in Europe in the fifties of the XVIII century, rubber was rejected for the second time.

    A well-known rubber eraser has paved the way for wide use of rubber. Until now, it remains unknown who first noticed the ability of rubber, or, as it was then called, "gummy-elastic", it is easy to "eat" pencil lines( it is clear that the name "eraser" is a free abbreviation of the now-out-of-use synonym for the word"rubber")."Father" eraser is considered to be the Englishman D. Priestley, although he only described in 1770 the discovery made by another man - a mechanic E. Nern. A little more than ten years passed, and one London coachman was not afraid to spoil his coat, smeared it with rubber mortar to protect himself from the rain. From that moment, new material began to conquer the world.

    In Vienna in 1821, the first factory of rubber products was opened. In France, by this time, braces and garters were already made from him. In England there were the first waterproof coats, named for their inventor by the mackintosh.

    In the 20th century natural rubber was replaced by synthetic rubber. For the first time its production was organized in our country under the leadership of Academician S. V. Lebedev. Rubber - the basis for the production of rubbers, which consist of one or more polymers and various chemical additives. Rubbers and rubber are united by one concept - "elastomers", thus emphasizing their main characteristic property - high elasticity. Rubber is "shoes" for cars, airplanes, bicycles, suits for divers, inflatable dams to protect cities from floods and much, much more.

    And what about the eraser? He has changed little since ancient times. True, he is now being made not from natural, but artificial rubber and he has younger brothers, for example, electro-elastic. It makes it easier for the draftsmen. This mechanical stiralk is called wireless. The electric motor driving the elastic band is powered not from the mains, but from the built-in battery housing. But the usual eraser on the rubber base mascara does not erase. And there was a novelty. It consists of plastic microcapsules filled with a solvent. Friction destroys the capsule shell, the solvent rinses and discolours mascara. This eraser can be used to erase mascara from tracing paper and from a plastic film, which is increasingly being drawn in our time. But with inkman this mascara can not be erased: it penetrates into the paper too deeply.

    Collection of latex from Hevea.

    There is an eraser that can erase even printed text. Why is this necessary? Sometimes when preparing books for publication, the editor or proofreader needs to make small changes to the printed manuscript, remove or replace a few words. But the typographic impression is not taken by any elastic band, and all corrections have to be squeezed between words or lines. When the revision is easy and wrong. Therefore, an unusual "eraser" was designed. This is a miniature sandblaster, erasing a typographic text with a jet of fine abrasive powder.

    The spent powder, paper and paint particles are immediately sucked in by a micro-vacuum cleaner."Eraser" is suitable not only for making corrections to small circulation editions, but also for correcting drawings, and also for cleaning library books from traces left on pages by inaccurate readers.