Charles Goodyear

����������� Rubber was known long before the 2-(era/time/period) of Mr. Goodyear, but it had serious 3-(comebacks/drawbacks/troubles). In cold weather it would become hard and crack. In warm weather it would�become soft,�sticky and 4-(take off/send off/give off) a bad odor.

����������� Many people had tried to find ways to make rubber into a more 5-(satisfactory/better/exemplar) material and Charles Goodyear was one of them. He 6-(carried on/carried out/carried through) hundreds of experiments. He 7-(stirred/mixed/combines) many different compounds and substances with the rubber to see what 8-(happened/affect/effect) they would have.

����������� One day in 1839, while he was working 9-(on/to/about) one of his experiments, he accidentally dropped a 10-(bunch/piece/slice) of rubber on a hot stove. This rubber had been mixed with sulfur. The rubber and sulfur charred 11-(however/due to/despite) they did not burn. When Goodyear 12-(tried with/tried out/sent out) this rubber combination, he found that it was 13-(best/better/finer) than any other rubber he had seen. It did not get sticky and 14-(give off/get off/set off) a bad smell when it was 15-(cooled/warmed/wet). Cold did not make it crack. The sulfur and the heat 16-(together/altogether/one another) had changed the rubber in some way.

����������� Goodyear�s method of 17-(handling/mixing/preparing) rubber is called �vulcanization�. This word comes from �Vulcan�, the Roman God of Fire.

����������� Charles Goodyear did not make a 18-(money/fortune/bargain) from his discovery. In fact, at one point in his 19-(live/lives/life), he was put into debtor�s prison and when he died in 1860, he was 20- (already/still/yet) deeply in debt.

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