CELESTIAL PHENOMENA. 67 



Man learns to know the external world through the organs 

 of the senses. Phenomena of light proclaim the existence of 

 matter in remotest space, and the eye is thus made the medium 

 through which we may contemplate the universe. The dis- 

 covery of telescopic vision more than two centuries ago, has 

 transmitted to latest generations a power, whose limits are 

 as yet unattained. 



The first and most general consideration in the Cosmos is that 

 of the contents of space ,- the distribution of matter, or of crea- 

 tion, as we are wont to designate the assemblage of all that is 

 und ever will be developed. We see matter either agglomerated 

 into rotating, revolving spheres of different density and size, 

 or scattered through space in the form of self-luminous vapour. 

 If we considei first the cosmical vapour dispersed in definite 

 nebulous spots, its state of aggregation will appear constantly 

 to vary. Sometimes appearing separated into round or ellip- 

 tical discs, single or in pairs, occasionally connected by a 

 thread of light ; whilst, at another time, these nebula3 occur 

 in forms of larger dimensions, and are either elongated, or 

 variously branched, or fan-shaped, or appear like well-defined 

 rings, enclosing a dark interior. It is conjectured that these 

 bodies are undergoing variously developed formative processes, 

 as the cosmical vapour becomes condensed in conformity with 

 the laws of attraction, either round one or more of the nuclei. 

 Between two and three thousand of such unresolvable nebula?, 

 in which the most powerful telescopes have hitherto been 

 unable to distinguish the presence of stars, have been counted, 

 and their positions determined. 



The genetic evolution that perpetual state of development 

 which seems to affect this portion of the regions of space- 

 has led philosophical observers to the discovery of the analogy 

 existing among organic phenomena. As in our forests we see 

 the same kind of tree in all the various stages of its growth, 

 and are thus enabled to form an idea of progressive, vital 

 development; so do we also in the great garden of the uni- 

 verse recognise the most different phases of sidereal formation. 

 The process of condensation, which formed a part of the 

 doctrines of Anaximenes, and of the Ionian School, appears 

 to be going on before our eyes. This subject of investigation 

 and conjecture is especially attractive to the imagination, for 

 in the study of the animated circles of nature, and of the 



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