Edison discovered electricity. But it did not happen overnight! To find a fiber to burn inside the bulb,he experimented with other 2000 items.One of his friends travelled 2300 miles to the source of the River Amazon, in search of a suitable fiber.
Another travelled 30,000 miles through China and India.
Yet another went to Japan. Edison spent $100,000 on this experiment before success smiled on him. We owe the miracle of light as much to his perseverance as to his GENIUS.