Proceedings of the British Association. 9/ 



directed, as well as to some points in the philosophy of science ge- 

 nerally, in which it appears to me that a disposition is becoming 

 prevalent towards lines of speculation, calculated rather to bewilder 

 than enlighten, and, at all events, to deprive the pursuit of science of 

 that which, to a rightly constituted mind, must ever be one of its 

 highest and most attractive sources of interest, by reducing it to 

 a mere assemblage of marrowless and meaningless facts and laws. 



The last year must ever be considered an epoch in Astronomy, 

 from its having witnessed the successful completion of the Earl 

 of Rosse's six-feet reflector — an achievement of such magnitude, 

 both in itself as a means of discovery, and in respect of the difficulties 

 to be surmounted in its construction, (difficulties which perhaps few 

 persons here present are better able from experience to appreciate 

 than myself), that I want words to express my admiration of it. I 

 have not myself been so fortunate as to have witnessed its perform- 

 ance, but from what its noble constructor has himself informed me 

 of its effects on one particular nebula, with whose appearance in 

 powerful telescopes I am familiar, I am prepared for any statement 

 which may be made of its optical capacity. What may be the effect 

 of so enormous a power in adding to our knowledge of our own 

 immediate neighbours in the universe, it is of course impossible to 

 conjecture ; but for my own part I cannot help contemplating, as one 

 of the grand fields open for discovery with such an instrument, those 

 marvellous and mysterious bodies or systems of bodies, the Nebulae. 

 By far the major part, probably, at least, nine-tenths of the nebulous 

 contents of the heavens consist of nebulae of spherical or elliptical 

 forms, presenting every variety of elongation and central condensation. 

 Of these a great number have been resolved into distinct stars, and a 

 vast multitude more have been found to present that mottled appear- 

 ance, which renders it almost a matter of certainty, that an increase 

 of optical power would show them to be similarly composed. A 

 not unnatural or unfair induction would therefore seem to be, that 

 those which resist such resolution do so only in consequence of the 

 smallness and closeness of the stars of which they consist ; that, in 

 short, they are only optically and not physically nebulous. There is, 

 however, one circumstance which deserves especial remark, and 

 which, now that my own observation has extended to the nebulae 



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