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Скачать Tales About Metal by S.Venetsky бесплатно

Tales About Metal by S.Venetsky
Mir Publisher Moscow | 1988 | ISBN: 5030000542 | Pages: 216 | PDF | 81.24 MB

For ages have metals faithfully served humanity in all its endeavours to conquer the elements, unravel the mysteries of Nature and build powerful machines and installations. The world of metals is diverse and absorbing. The history of some of its representatives, notably, copper, iron, lead, mercury, gold, silver and tin dates thousands of years back. Others were discovered within just a few recent decades.

The properties of metals are extremely varied. Mercury will not freeze even at below-zero temperatures, while tungsten will not be consumed by the hottest of flames. Lithium could make a fine swimmer, being half as heavy as water and unable to sink no matter how hard it would try; osmium is a heavy-weight champion among metals and, thrown into water, will hit the bottom faster than a stone.

Silver "gladly" conducts electricity, while titanium has an aversion to this "pastime": its electrical conductivity is only a 3OOth part that of silver. We come across iron wherever we turn and holmium is found in such minute quantities in the earth's crust that it is fabulously expensive: a grain of pure holmium is several hundred times more expensive than gold. But for all their differences, metals have one thing in common—they all belong to one large family. S. I. Venetsky's Tales About Metals contains much information on the history of discovery of many metals and on their present and future uses.

It was not the author's idea to give any systematized account of every metal he tells about. The history of metals abounds in amazing incidents, at times romantic or humorous, at times tragic. And it is mostly this aspect that the author had in mind when he wrote his book. The book is intended for those who are ever curious, not only youngsters who are just discovering the world of science for themselves, but also those who have probably said goodbye to school and college, but still seize upon every opportunity to learn more about things around them.

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