In the small hours of the morning of 22d February, 1901, Dr. Anderson of Bonnington, Edinburgh, saw a bright star shining in the constellation of Perseus, where he knew no such star was ever seen before. The circumstances connected with this discovery afford another striking instance of how Nature keeps her secrets for her true amateur, using the word in its highest sense. The evening of 21st February was cloudy, and nine out of ten astronomers would have gone to bed when there seemed little prospect of the night clearing; but Dr. Anderson was the tenth man. At twenty minutes to three in the morning the clouds rolled away from over the old gray Scottish capital, and the trained eye of the patient observer saw right in the heart of Perseus a new star. Never before had its light, blue-white, like an unpolished diamond, shone down on this strange earth of ours. Next day the news of the wonderful discovery was flashed to all the great observatories of the world, and telescopes and spectroscopes, cameras and photometers, were directed toward the strange phenomenon, and by testing, measuring, examining, sought to wrest its secrets from it. Much is still a mystery; but what has been ascertained during the period that the rhythm of its light-waves beat upon our shores is of great interest and importance as bearing directly on the life-history of each individual star in the heavens, and of our own sun and planet among them. The first and simplest question that arises for settlement is the date when the new star blazed forth in our terrestrial sky. The curious reader will notice the reservation: in _our_ terrestrial sky. When the star _actually_ burst forth into resplendent light is another matter, as we shall discover later on. It was certainly before Dr. Anderson was born, and probably before another Scotsman—Ferguson by name—combined, like many another sage, counting and watching sheep with counting and watching stars. With regard to the date of the appearance in our sky of the new star, Nova Persei, as it is called in astronomical literature, when Dr. Anderson discovered it at twenty minutes to three o’clock on the morning of 22d February, it was bright enough to be straightway evident to a trained astronomer. In these later days of strenuous scientific activities every portion of the sky is constantly being examined and charted, and no sooner was the discovery of Nova Persei announced than a searching of records began, in order to ascertain if, at any time, the star had ever been seen before. [Illustration: Fig. 19.—Chart Showing Position of Nova Persei]