Bell went back to teaching deaf-mutes.He has since busied himself with the study of airplanes and wireless, and has invented an instrument for transmitting sound by light.The new telephone company offered him $10,000 a year as chief inventor, but he replied that he could not invent to order.Thomas Sanders received somewhat less than $1,000,000 and lost most of it exploiting a Colorado gold mine.Gardiner Hubbard withdrew from business and devoted the last years of his life to the National Geographic Society.Thomas Watson, after retiring from the telephone business, bought a ship-building yard near Boston, which has been successful.
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