For ages past men have known and watched the planets lying within the orbit of Saturn, and they had made up their minds that this was the limit of our system. But in 1781 a great astronomer named Herschel was watching the heavens through a telescope when he noticed one strange object that he was certain was no star. The vast distance of the stars prevents their having any definite outline, or what is called a disc. The rays dart out from them in all directions and there is no 'edge' to them, but in the case of the planets it is possible to see a disc with a telescope, and this object which attracted Herschel's attention had certainly a disc. He did not imagine he had discovered a new planet, because at that time the asteroids had not been found, and no one thought that there could be any more planets. Yet Herschel knew that this was not a star, so he called it a comet! He was actually the first who discovered it, for he knew it was not a fixed star, but it was after his announcement of this fact that some one else, observing it carefully, found it to be a real planet with an orbit lying outside that of Saturn, then the furthest boundary of the solar system. Herschel suggested calling it Georgius Sidus, in honour of George III., then King; but luckily this ponderous name was not adopted, and as the other planets had been called after the Olympian deities, and Uranus was the father of Saturn, it was called Uranus. It was subsequently found that this new planet had already been observed by other astronomers and catalogued as a star no less than seventeen times, but until Herschel's clear sight had detected the difference between it and the fixed stars no one had paid any attention to it. Uranus is very far away from the sun, and can only sometimes be seen as a small star by people who know exactly where to look for him. In fact, his distance from the sun is nineteen times that of the earth. Yet to show at all he must be of great size, and that size has actually been found out by the most delicate experiments. If we go back to our former comparison, we shall remember that if the earth were like a greengage plum, then Uranus would be in comparison about the size of one of those coloured balloons children play with; therefore he is much larger than the earth. In this far distant orbit the huge planet takes eighty-four of our years to complete one of his own. A man on the earth will have grown from babyhood to boyhood, from boyhood to the prime of life, and lived longer than most men, while Uranus has only once circled in his path.