The remarkable successes of astronomical photography, which depended upon the plate's power of accumulation of a very feeble light acting continuously through an exposure of several hours, were worthy to be regarded as a new revelation. The first chapter opened when, in 1880, Dr. Henry Draper obtained a picture of the nebula of Orion; but a more important advance was made in 1883, when Dr. Common, by his photographs, brought to our knowledge details and extensions of this nebula hitherto unknown. A further disclosure took place in 1885, when the Brothers Henry showed for the first time in great detail the spiral nebulosity issuing from the bright star Maia of the Pleiades, and shortly afterward nebulous streams about the other stars of this group. In 1886 Mr. Roberts, by means of a photograph to which three hours' exposure had been given, showed the whole background of this group to be nebulous. In the following year Mr. Roberts more than doubled for us the great extension of the nebular region which surrounds the trapezium in the constellation of Orion. By his photographs of the great nebula in Andromeda, he had shown the true significance of the dark canals which had been seen by the eye. They were in reality spaces between successive rings of bright matter, which appeared nearly straight, owing to the inclination in which they lay relatively to us. These bright rings surrounded an undefined central luminous mass. Recent photographs by Mr. Russell showed that the great rift in the Milky Way in Argus, which to the eye was void of stars, was in reality uniformly covered with them. THE STORY OF THE HEAVENS.