lessons to his pupils per week; groaning and fretting under the incapacity of not a few of them—a man who had to be in his place conducting a band or a concert, and supervising a church's music, or who, instead of seeking rest in sleep, when the day's weary work was done, would often spend the night in observing the stars. His sister, who was his invariable companion in these night watches, had ample reason to say of him, "He did in one season more than anyone else could have done, and would have resumed the hunt [for Saturn's satellites] the next fifteen years, if nothing had interfered."
The new path on which he entered, and which led him into other and most attractive fields of inquiry, was the distance of what are called the fixed stars from the solar system. He knew that at the distance of the nearest of them, twice the sun's distance from the earth, immense though it seems, appears no bigger than a needle point, and cannot be used as a base line for measurement, or, indeed, as a line at all. He gave up the thought of attempting to solve the problem from that, the most natural and the easiest side. It was good for neighbours so near us as Mars and Venus. It was useless for Sirius or Arcturus. Following, perhaps, the example of Galileo, he believed that observations on stars so close together that neither the naked eye nor ordinary telescopes could separate them, and make two out of one, would lead to a discovery of their distance. He did not succeed in his purpose, but he was "introduced to a new series of observations and discoveries." He resolved to examine every star in the heavens with the utmost attention and a very high power, that he might collect such
