Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667

List of thumbnails

< >
311
311
312
312
313
313
314
314
315
315
316
316
317
317
318
318
319
319
320
320
< >
page |< < of 701 > >|
1tion, may be by us obſerved in the fixed ſtars to be of two
kinds: The one is, that of their apparent magnitudes varied,
cording as we, tranſported by the Earth, approach or recede
from the ſame: The other (which likewiſe dependeth on the
ſame acceſſion and reeeſſion) their appearing unto us in the
ſame Meridian, one while more elevated, and another while leſſe.
Moreover, you tell us (and I underſtand it very well) that the
one and other of theſe mutations are not made alike in all the
ſtars, but in ſome greater, and in others leſſer, and in others not
at all.
The acceſſion and receſſion whereby the ſame ſtar ought
to appear, one while bigger, and another while leſſer, is
ble, and almoſt nothing in the ſtars neer unto the pole of the
cliptick, but is greateſt in the ſtars placed in the Ecliptick it ſelf,
and indifferent in the intermediate: the contrary happens in the
other difference, that is, the elevation or depreſſion of the ſtars
placed in the Ecliptick is nothing at all, greateſt in thoſe neereſt
to the Pole of the ſaid Ecliptick, and indifferent in the
diate.
Beſides, both theſe differences are more ſenſible in the
Stars neereſt to us, in the more remote leſſe ſenſible, and in
thoſe that are very far diſtant wholly diſappear.
This is, as to
what concerns my ſelf; it remaineth now, as I conceive, that
ſomething be ſaid for the ſatisfaction of Simplicius, who, as I
believe, will not eaſily be made to over-paſſe thoſe differences,
as inſenſible that are derived from a motion of the Earth ſo vaſt,
and from a mutation that tranſports the Earth into places twice
as far diſtant from us as the Sun.
The Epilogue of
the Phænomena
of the fixed ſtars
cauſed by the
nual motion of the
Earth.
SIMP. Truth is, to ſpeak freely, I am very loth to confeſſe, that
the diſtance of the fixed Stars ought to be ſuch, that in them the
fore-mentioned differences ſhould be wholly imperceptible.
SALV. Do notthrow your ſelf into abſolute deſpair,
cius, for there may perhaps yet ſome qualification be found for
your difficulties.
And firſt, that the apparent magnitude of the
ſtars is not ſeen to make any ſenſible alteration, ought not to be
judged by you a thing improbable, in regard you ſee the gueſſes
of men in this particular to be ſo groſſely erroneous, eſpecially in
looking upon ſplendid objects; and you your ſelf beholding
v. g. a lighted Torch at the diſtance of 200 paces, if it

proach nearer to you 3. or 4. yards, do you think that it will
ſhew any whit encreaſed in magnitude?
I for my part ſhould
not perceive it certainly, although it ſhould approach 20. or
30. yards nearer; nay it hath ſometimes happened that in ſeeing
ſuch a light at that diſtance I know not how to reſolve whether
it came towards me, or retreated from me, when as it did in
reality approach nearer to me.
But what need I ſpeak of this?
If the ſelf ſame acceſſion and receſſion (I ſpeak of a diſtance

Text layer

  • Dictionary
  • Places

Text normalization

  • Original
  • Regularized
  • Normalized

Search


  • Exact
  • All forms
  • Fulltext index
  • Morphological index