ASTRONOMICAL SOCIETIES AND ASTRONOMERS. 821 



The durations of the movements of the planets are immense. The 

 variations presented in the periods of the stars occur by thou- 

 sands of centuries. It takes light millions of years to cross the 

 distances that separate the stars from one another. What can be 

 said of the immensity of those worlds as compared with which 

 the earth is but an atom, of the prodigious multitude of the suns 

 of space, more numerous than the grains of sand at the bottom of 

 the sea, and of those velocities with which all the stars are carried 

 in immense whirls across the infinite ? 



But you tell me astronomy is a perfect science ; it has reached 

 the height of knowledge, and there is nothing left in it for the 

 amateur. I answer that there is always something to be reaped 

 in the astronomical field of investigation for both the learned and 

 the modest amateur. How many times has it not been said that 

 all was known ; and then, as the power of modern instruments 

 was increased and new methods of investigation were invented, 

 new conquests were made in the sidereal domain ! Galileo's tele- 

 scope had immense treasures to look for in the sky. In this age 

 the improvements in the telescope have made known Uranus and 

 Neptune and more than three hundred minor planets, with, a few 

 years ago, the two satellites of Mars. Numerous comets and hun- 

 dreds of smaller nebulae discovered every year give additional 

 proof that a harvest is always awaiting reapers in the sky. When 

 we consider the immensity of the universe, how could it be other- 

 wise ? 



Analogy teaches us that the sun is one of the innumerable 

 stars that spangle the firmament with their lights, and that each 

 star is the center of a system like that to which we belong, and 

 of which the sun is the center. Of all these suns, centers of plan- 

 etary systems, only a few thousand are visible to the naked eye, 

 while telescopes reveal millions of them. Then, if we consider 

 the nebula? those little milky spots scattered in all the zones of 

 the sky if we remark that nearly all of them can, by the aid of 

 strong optical powers, be resolved into thousands of luminous 

 points, and that consequently they are presented to our eyes as 

 immense milky ways investing distant universes, we arrive at the 

 astounding conclusion that little vaporous nothings, which we 

 can hardly distinguish with our strongest instruments, form, not 

 a universe like our solar system, but that each of them is an 

 agglomeration of myriads of universes, the extent and number of 

 which can not be imagined. Translated for The Popular Science 

 Monthly from Ciel et Terre. 



