These openings were, however, only regarded as
transient, while the reason of their being luminous and fiery, instead of
obscure, was supposed to be owing to the
p 153
translucent illuminated ether which lay beyond them.*
[footnote] *Aristot., 'Meteor.', ii.,, 5, 1. Seneca, 'Natur. Quaest.', i.,
14, 2. "Coelum discessisse," in Cic., 'de Divin.', i., 43.
Derham, and even Huygens, did not appear disinclined to explain in a similar
manner the mild radiance of the nebulae.*
[footnote] *Arago, in the 'Annuaire', 1842, p. 429.
When we compare the stars of the first magnitude, which, on an average, are
certainly the nearest to us, with the non-nebulous telescopic stars, and
further, when we compare the nebulous stars with unresolvable nebulae, for
instance, with the nebula in Andromeda, or even with the so-called planetary
nebulous vapor, a fact is made manifest to us by the consideration of the
varying distances and the boundlessness of space, which shows the world of
phenomena, and that which constitutes its causal reality, to be dependent
upon the 'propagation of light'. The velocity of this propagation is
according to Struve's most recent investigations, 166,072 geographical miles
in a second, consequently almost a million of times greater than the
velocity of sound.
Pages:
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318