element of surface of revolution

1) (химический) элемент

2) (гальванический) элемент, первичный источник тока

3) элемент (конструкции, машины, схемы); компонент; (составная) часть; деталь

4) орган ( станка)

5) устройство; узел, блок; звено; схема

1) поверхность

SUBJECT AREA: Paper and printing

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Fourdrinier's father was a paper manufacturer and stationer of London, from a family of French Protestant origin. Henry took up the same trade and, with his brother Sealy (d. 1847), devoted many years to developing the papermaking machine. Their first patent was taken out in 1801, but success was still far off. A machine for making paper had been invented a few years previously by Nicolas Robert at the Didot's mill at Essonnes, south of Paris. Robert quarrelled with the Didots, who then contacted their brother-in-law in England, John Gamble, in an attempt to raise capital for a larger machine. Gamble and the Fourdriniers called in the engineer Bryan Donkin, and between them they patented a much improved machine in 1807. In the new machine, the paper pulp flowed on to a moving continuous woven wire screen and was then squeezed between rollers to remove much of the water. The paper thus formed was transferred to a felt blanket and passed through a second press to remove more water, before being wound while still wet on to a drum. For the first time, a continuous sheet of paper could be made. Other inventors soon made further improvements: in 1817 John Dickinson obtained a patent for sizing baths to improve the surface of the paper; while in 1820 Thomas Crompton patented a steam-heated drum round which the paper was passed to speed up the drying process. The development cost of £60,000 bankrupted the brothers. Although Parliament extended the patent for fourteen years, and the machine was widely adopted, they never reaped much profit from it. Tsar Alexander of Russia became interested in the papermaking machine while on a visit to England in 1814 and promised Henry Fourdrinier £700 per year for ten years for super-intending the erection of two machines in Russia; Henry carried out the work, but he received no payment. At the age of 72 he travelled to St Petersburg to seek recompense from the Tsar's successor Nicholas I, but to no avail. Eventually, on a motion in the House of Commons, the British Government awarded Fourdrinier a payment of £7,000. The paper trade, sensing the inadequacy of this sum, augmented it with a further sum which they subscribed so that an annuity could be purchased for Henry, then the only surviving brother, and his two daughters, to enable them to live in modest comfort. From its invention in ancient China (see Cai Lun), its appearance in the Middle Ages in Europe and through the first three and a half centuries of printing, every sheet of paper had to made by hand. The daily output of a hand-made paper mill was only 60–100 lb (27–45 kg), whereas the new machine increased that tenfold. Even higher speeds were achieved, with corresponding reductions in cost; the old mills could not possibly have kept pace with the new mechanical printing presses. The Fourdrinier machine was thus an essential element in the technological developments that brought about the revolution in the production of reading matter of all kinds during the nineteenth century. The high-speed, giant paper-making machines of the late twentieth century work on the same principle as the Fourdrinier of 1807.

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