To be untiring means to be without losing hope, determined to succeed and believing in yourself all the time. It is the untiring minds who reach their goal, time and again, making the world better and brighter with their effort. This is the story of Thomas Alva Edison, who, with 1903 patents to his name, is perhaps the greatest inventor to have ever walked the earth. Read how his untiring effort, working day and night without losing hope, helped to light up the entire world with his new source of light.