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  • Brainly User
2016-02-12T06:14:03+05:30
Natural rubber is one of nature's unique materials. The Native Americans of tropical South America's Amazon basin knew of rubber and its uses long before Christopher Columbus's explorations brought it to the attention of Europeans. The Indians made balls of rubber by smoking the milky, white latex of trees of the genus Hevea that had been placed on a wooden paddle, to promote water evaporation and to cure the substance. Spanish navigator and historian Gonzalo Fernández de Oviedo y Valdes (1478–1557) was the first European to describe these balls to a European audience. In 1615 a Spanish writer enumerated the practical uses of rubber. He reported that the Indians waterproofed their cloaks by brushing them with this latex and made waterproof shoes by coating earthen molds with it and allowing these coatings to dry. In 1735 interest was revived in this unusual substance when French mathematical geographer and explorer Charles-Marie de La Condamine (1701–1774) sent several rolls of crude rubber to France with an accompanying description of products made from it by the South American natives. Although it met with some use in waterproofing boots, shoes, and garments, it largely remained a museum curiosity. Crude rubber possessed the valuable properties of elasticity, plasticity, strength, durability, electrical nonconductivity, and resistance to water; however, products made from it hardened in winter, softened and became sticky in summer, were attacked by solvents, and smelled bad...
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2016-02-13T17:19:48+05:30
Natural rubber is one of nature's unique materials. The Native Americans of tropical South America's Amazon basin knew of rubber and its uses long before Christopher Columbus's explorations brought it to the attention of Europeans.
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