104 COSMOS. 



summits. According to what modern geology has taught ii8 

 to conjecture regarding the ancient history of our atmosphere, 

 its primitive condition, in respect to its mixture and density, 

 must have been unfavorable to the transmission of hght. 

 When we consider the numerous processes which, in the pri- 

 maiy world, may have led to the separation of the solids, 

 fluids, and gases around the earth's surface, the thought in- 

 voluntarily arises how narrowly the human race escaped be* 

 ing surrounded with an untransparent atmosphere, wliich, 

 though perhaps not greatly prejudicial to some classes of 

 vegetation, would yet have completely veiled the whole of 

 the starry canopy. All knowledge of the structure of the 

 universe would thus have been withheld from the inquiring 

 spirit of man. Excepting our own globe, and perhaps the 

 sun and the m^oon, nothing would have appeared to us to 

 have been created. An isolated triad of stars — the sun, the 

 moon, and the earth — would have appeared the sole occu- 

 pants of space. Deprived of a great, and, indeed, of the sub- 

 limest portion of his ideas of the Cosmos, man would have 

 been left without all those incitements which, for thousands 

 of years, have incessantly impelled him to the solution of 

 important problems, and have exercised so beneficial an in- 

 fluence on the most brilliant progress made in the higher 

 spheres of mathematical development of thought. Before 

 we enter upon an enumeration of what has already been 

 achieved, let us dwell for a moment on the danger from 

 which the spiritual development of our race has escaped, and 

 the physical impediments which would have formed an im- 

 passable barrier to our progress. 



In considering the number of cosmical bodies which fill 

 the celestial regions, three questions present themselves to 

 our notice. How many fixed stars are visible to the naked 

 eye ? How many of these have been gradually catalogued, 

 and their places determined according to longitude and lat- 

 itude, or according to their right ascension and declination ? 

 What is the number of stars from the first to the ninth and 

 tenth magnitudes which have been seen in the heavens by 

 means of the telescope ? These three questions may, from 

 the materials of observation at present in our possession 

 be det3rm.ined at least approximatively. Mere conjectures 

 based on the gauging of the stars in certain portions of the 

 Milky Way, differ from the preceding questions, and refer to 

 the theoretical solution of the question : How many stara 

 might be distinguished throughout the whole heavens with 



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