Page:Popular Science Monthly Volume 84.djvu/211

Rh which it is hoped that all the affiliated societies will unite so that the men of science of the. whole country may be brought together and the importance and magnitude of their scientific work may serve as a stimulus to them and an impressive lesson to the general public.

his presidential address before the association Professor Pickering stated j that American universities and colleges devoted a hundred times as much time and money to diffusing human knowledge as to the object of the American Association of Science. The greatest need of science at the present time is the means for aiding the real men of genius.

The first catalogue of the stars was made by Hipparchus two thousand years ago. A thousand years later it was revised by a Persian astronomer Sufi. They show not only that the positions and brightness of the stars have changed but little in two thousand years, but that the same may be said of the sensitiveness of the human eye to. lights of different colors. The places of the stars were first accurately determined