THE NEBULAR HYPOTHESIS. 659 



gave stellar spectra. Among the true nebulae may be mentioned, the 

 Annular Nebula in Lyra ; the Dumb-bell Nebula ; and the great 

 Nebula in the Sword-handle of Orion concerning the nature of which 

 there has been so much discussion, 



These spectrum investigations afford tangible and unmistakable 

 evidence that there are in space, masses of ignited gaseous or vaporous 

 matter of prodigious extent, shining by their own light, and resem- 

 bling the vast nebula which the Nebular Hypothesis declares to have 

 been the original condition of our solar system. The nebulous matter, 

 assumed as the basis of the hypothesis, is no figment of the theorist ! 



What great results have been achieved by the power of means 

 apparently the most trivial ! Immense objects, seemingly unattain- 

 able, have been grasped by the smallest conceivable handle ! A little 

 instrument, which is scarcely any thing more than a small triangular 

 piece of glass, solves questions which hundreds of thousands of dollars 

 expended in telescopes, and years of observation, could not have 

 settled ! Penetrating into the illimitable depths of space, it reveals to 

 us something of the physical and chemical constitution of stellar clus- 

 ters and nebulae, so remote, that the light which the spectroscope ana- 

 lyzes, must have left them thousands, perhaps millions, of years ago ! 



The lecturer concluded with the following reflections, which are 

 given without abridgment : 



In contemplating the vastness of the sidereal universe, every person, 

 in every age and country, must recognize as irresistibly natural, the 

 train of thought expressed by the Hebrew Psalmist, when he ex- 

 claims : " When I consider thy heavens, the work of thy fingers, 

 the moon and the stars, which thou hast ordained ; what is man, that 

 thou art mindful of him? and the son of man, that thou visitest 

 him ? " (Psalm viii. 3, 4.) 



How incalculably has this withering sense of insignificance been 

 augmented by modern telescopic excursions into the remote recesses 

 of the stellar universe ! When, by measurements, in which the evi- 

 dence of the method advances pari passu with the precision of the re- 

 sults, the volume of the earth is reduced to less than one-millionth 

 part of the volume of the sun ; when the sun himself, transported to 

 the region of the stars, takes up a very modest place among the thou- 

 sand of millions of those bodies revealed to us by the telescope; when 

 the ninety-five millions of miles which separate the earth from the sun, 

 by reason of their comparative smallness, have become a base totally 

 insufficient for ascertaining the dimensions of the visible universe , 

 when even the swiftness of light barely suffices for the common valu- 

 ations of science ; when, in short, by a chain of irresistible j)roofs, cer- 

 tain stars and nebulae have retired to distances that light could not 

 traverse in less than millions of years we feel as if annihilated by 

 the immensity of the scale of the universe ! In assigning to man, and 

 to the planet he inhabits, so small so insignificant a position in the 



