_Syrius_ and the Sun, proportionable to the Magnitude of the Sphere of
our Comets, &_c._ represented at S, whereby it evidently appears, that
as all the Planets of _Syrius_ must be included within the small Sphere
represented in the Center P, none of them could possibly be seen at the
Sun, not only by reason of the Smallness of the Angle of Sustension, or
Elongation, but also as being lost in the superior Light of _Syrius_
himself, in so minute an Orb of Vicinity.
Consequently (as you must perceive) no Arguments can possibly be drawn
to deny the Existence of such Bodies, with any Shew of Reason, from
their not having been seen by us.
Here I must observe to you, that you cannot consider this Scale of
Orbits too much before you look upon Plate XVII.
To conclude, it evidently seems to be the End and Design of Providence,
by this visible Variety of Beings, to lift the Minds of Men above this
narrow Earth, in Search of that powerful Being upon which we are all
so much dependant; and the _Creator_, no doubt, in this vast Display
of his Wisdom and Power, designed the amazing Whole, as the adequate
Object of every Part, and as such equally open on all Sides, to the
penetrating Progress of human Minds, and through the most extensive
Faculty of Sense, the _Sight_, to draw our Reason and Understanding by
Degrees, from finite Objects into Infinity; and as the last Result of
celestial Contemplations place within our Reach, a certain Evidence of
a future State, _and the manifest Mansions of Rewards and Punishments,
suited no doubt most equitably to all Degrees of Virtue, and to every
Vice_.
"When I consider (says Mr. _Addison_, speaking as having taken
particular notice of a fine Evening) that infinite Host of Stars, or
to speak more philosophically of Suns, which were then shining upon
me, with those innumerable Sets of Planets or Worlds, which were then
moving round their respective Suns; when I still enlarge the Idea,
and supposed another Heaven of Suns and Worlds rising still above
this which we discovered; and these still enlightened by a superior
Firmament of Luminaries, which are planted at so great a Distance, that
they may appear to the Inhabitants of the former as the Stars do to
us; in short, whilst I pursued this Thought, I could not but reflect
on that little insignificant Figure which I myself bore amongst the
Immensity of God's Works:" This Reflection, I judge, as you are an
Admirer of the Author, you will not look upon as impertinent in this
Place, especially as it must enforce what I have endeavoured to shew
you, namely, the Reasonableness of a Plurality of sidereal Systems, and
their Multiplicity of Worlds; which, if you are yet in Doubt of, I hope
you will at least forgive so well designed an Attempt with your usual
Candour.
I am now prepared to proceed in the chief Design of this Undertaking,
which is to solve the Phænomena of the _Via Lactea_; and propose in my
next to answer more fully your farther Request.
_I am_, &c.
[Illustration]
LETTER the FIFTH.
_Of the Order, Distance, and Multiplicity of the Stars, the_ Via
Lactea, _and Extent of the visible Creation_.
_SIR_,
WE are told, and, if I remember right, it is also your Opinion, that
three of the finest Sights in Nature, are a rising Sun at Sea, a
verdant Landskip with a Rainbow, and a clear Star-light Evening: All
of which I have myself often observed with vast Delight and Pleasure.
The first I have frequently beheld, and always with an agreeable
Surprize; the second I have as often taken notice of, with no small
Degree of Admiration; but the last I shall never look up to without an
Astonishment, even mixed with a kind of Rapture. The Night you last
left us, this admirable Scene was in its full Beauty; and, as _Milton_
says,
Silence was pleas'd: now glow'd the Firmament
With living Saphirs; _Hesperus_ that led
The starry Host rode brightest.----
I found it was impossible to look long upon this stupendious Scene, so
full of amazing Objects, and particularly the _Via Lactea_, which (the
Moon being absent) was then in great Perfection, without being put in
Mind of my Task. This surprizing Zone of Light being the chief Object I
have undertaken to treat of and demonstrate.
This amazing Phænomenon which have been the Occasion of so many
_Fables_, idle Romances, and ridiculous Opinions amongst the Antients,
still continues to be unaccounted for, and even in an Age vain enough
to boast Astronomy in its utmost Perfection.
What will you say, if I tell you, it is my Belief we are so far from
the real Summit of the Science, that we scarce yet know the Rudiments
of what may be expected from it. This luminous Circle has often
engrossed my Thoughts, and of late has taken up all my idle Hours;
and I am now in great Hopes I have not only at last found out the
real Cause of it, but also by the same Hypothesis, which solves this
Appearance, shall be able to demonstrate a much more rational Theory of
the Creation than hitherto has been any where advanced, and at the same
Time give you an intire new Idea of the Universe, or infinite System
of Things. This most surprizing Zone of Light, which have employed
successively for many Ages past, the wisest Heads amongst the Antients,
to no other Purpose than barely to describe it; we find to be a perfect
Circle, and nearly bisecting the celestial Sphere, but very irregular
in Breadth and Brightness, and in many Places divided into double
Streams.
[U]The principal Part of it runs through the _Eagle_, the _Swan_,
_Cassiopea_, _Perseus_, and _Auriga_, and continues its Course by the
Head of _Monoceros_, along by the greater _Dog_ through the Ship, and
underneath the _Centaur's Feet_, till having passed the _Alter_, the
_Scorpion's Tail_, and the Bow of _Aquarius_, it ends at last where it
begun.
[Footnote U:
----Carried toward the opposed _Bears_,
Its Course close by the _Artick_ Circle steers,
And by inverted _Cassiopea_ tends;
Thence by the _Swan_ obliquely it descends
The Summer Tropick, and _Jove's_ Bird divides;
Then cross the Equator, and the Zodiack glides
'Twixt _Scorpio's_ burning Tail, and the left Part
Of _Sagitarius_, near the fiery Dart;
Then by the other _Centaur's_ Legs and Feet,
Winding remounts the Skies (again to meet)
By _Argos'_ Topsail, and Heav'ns middle Sphere,
Passing the _Twins_, t' o'ertake the Charioteer;
Thence _Cassiopea_ seeking thee does run,
O're _Perseus_ Head, and Ends where it begun.
Sher. Manilius.
]
PLATE XII, and XIII.
Represents the two Hemispheres, where its true Tract is distinguished
amongst the principal Stars, and may easily be conceived by them to
circumscribe and bisect the whole Heavens.
This is that Phænomena I am about to explain and account for; but
before I proceed farther, I judge it will be no _improper Precognita_,
to give you the Thoughts of the Antients upon it; the Relation perhaps
may require some Patience; but I guess, that after reading such wild
and extravagant Notions concerning it, you will naturally judge more
favourably of the Conjectures of the Moderns upon it, and particularly
of what is concluded in the succeeding Pages.
[Illustration: Plate XII.]
[Illustration: Plate XIII.]
_Theophrastus_[V] was of Opinion, that the Hemispheres, which, by many
of the Antients were imagined to be solid, was joined together here;
and that this was the soldering of the two Parts into one. [W]Diodorus
thought it celestial Fire, of a dense and compact Nature, seen through
the Clifts or Cracks of the parting Hemisphere: But as _Manilius_ says,
Astonishment must sure their Senses reach,
To see the World's wide Wound, and Heav'n's eternal Breach.
[Footnote V: _Macrobius_, lib. i. cap. 15.
Or meets Heaven here! and this while Cloud appears
The Cement of the close-wedg'd Hemispheres!
]
[Footnote W:
The sacred Causes human Breasts enquire,
Whether the heavenly Segments there retire,
The whole Mass shrinking, and the parting Fame
Thro' cleaving Chinks admits the stranger Flame.
]
Oenopides[X] believed it the ancient Way of the Sun, till frighted at
the bloody Banquet of _Thyestis_. [Y]Eratosthenes supposed it _Juno's_
Milk, spilt whilst giving Suck to _Hercules_. [Z]Plutarch makes it the
Effect of _Phaeton's_ confused Erratication; but I think it is plain
[AA]Ovid judged them to be Stars, and the ancient _Ethnicks_ believed
them to be the blissful Seats of valiant and heroic Souls.
----Valiant Souls, freed from corporeal Gives,
Thither repair, and lead æthereal Lives.
Manilius.
[Footnote X:
Or seems that old Opinion of more Sway,
That the Sun's Horses here once run astray,
And a new Path mark'd in their straggling Flight,
Of scorching Skies, and Stars adusted Light.
]
[Footnote Y:
Nor must that gentle Rumour be supprest,
How Milk once flowing from fair _Juno's_ Breast
Stain'd the celestial Pavement, from whence came
This milky Path, its Cause shewn in its Name.
]
[Footnote Z:
When from the hurried Chariot Light'ning fled,
And scatter'd blazes all the Skies o'erspread;
By whose Approach new Stars enkindled were,
Which still as Marks of that sad Chance appear.
Manilius.
]
[Footnote AA:
A Way there is in Heaven's expanded Plain
Which when the Skies are clear, is seen below,
And Mortals by the Name of _Milky_, know,
The Ground-work is of Stars----
_Ovid's_ Met. lib. i.
]
But [AB]Democritus long ago believed them to be an infinite Number of
small Stars; and such of late Years they have been discovered to be,
first by _Gallaleo_, next by _Keplar_, and now confirmed by all modern
Astronomers, who have ever had an Opportunity of seeing them through a
good Telescope.
[Footnote AB: _Plutarch (in Placitis Philosoph.)_]
PLATE XIV.
Is from an Observation I made myself, of a bright Part of this Zone
near the Feet of _Antinous_; which, (by a Mistake of the Engraver) is,
as it appears through a Tube of two convex Glasses. I saw it through a
very good Reflector, and formed the Plan by a Combination of Triangles.
_Milton_ takes notice of this Zone in a most beautiful Manner, where he
describes the Creator's Return from his six Day's Work to Heaven, he
introduces it as a Simile to express his Idea of the eternal Way, or
Road to the celestial Mansions.
----A broad and ample Road, whose Dust is Gold
And Pavement Stars, as Stars to thee appear,
Seen in the _Galaxie_, that Milky Way,
Which nightly as a circling Zone thou seest
Powder'd with Stars.
But to infer from their Appearance only, that they are really Stars,
without considering their Nature and Distance; and that nothing but
Stars could possibly produce such an Effect, may perhaps be assuming
too much, when we have nothing but the bare Credit of the _Belgic_
Glasses to support our Conjectures; and although this may be sufficient
for any Mathematician, yet for your greater Satisfaction, I have
thought proper to give two or three more evincing Arguments, to confirm
these important Discoveries. _Democritus_, as I have said before,
believed them to be Stars long before Astronomy reaped any Benefit from
the improved Sciences of Optics; and saw, as we may say, through the
Eye of Reason, full as far into Infinity as the most able Astronomers
in more advantageous Times have done since, even assisted with their
best Glasses: And his Conjectures are almost as old as the philolaic
System of the Planets itself; the Construction of which, though
attempted by many, none have ever yet been able to confute.
The Light which naturally flows from this Crowd of radiant Bodies
is mixt and confused, chiefly occasioned by the Agitation of our
Atmosphere, and from a Union of their Rays of Light, by a too near
Proximity of their Beams, altogether they appear like a River of Milk,
but more of a pelucid Nature, running all round the starry Regions.
[Illustration: Plate XIV.]
For in the azure Skies its candid Way
Shines like the dawning Morn, or closing Day.
There are also many more such luminous Spaces to be found in the
Heavens of the same Nature with these, which we know to be Stars; in
particular the _Nebulæ_, or cloudy Star in the _Præsepe_ of 36; a
cloudy Star in _Orion_ of 21; [AC]a cloudy [AD]Knot not far from this
in the same Asterism of 80; in one Degree of the same Constellation
500, and in the whole Form above [AE]2000. All of which are great
Confirmations of the Truth of our Assertion, _i. e._ that this Zone of
Light proceeds from an infinite Number of small Stars. Here it will
not be amiss to observe, that it has been conjectured, and is strongly
suspected, that a proper Number of Rays, meeting from different
Directions, become Flame; and that hence it may prove not the Sun's
real Body which we daily see, but only his inflamed Atmosphere. I
begin to be of Opinion, and I think not without Reason, that the true
Magnitude of the Sun is not near what the modern Astronomers have made
it; and that it may not possibly be much above two Thirds of what it
appears to us; I don't mean that this Expansion of the solar Flame is
any Part of that dilated Light mentioned by Sir _Isaac Newton_, and
conceived to be round all light Bodies in general; but you may consider
it as not much differing from it, not of an unlike Nature, only greater
in Degree, and peculiar to the Sun and Stars, who are all, as has been
before in a manner demonstrated to be actually Globes of Fire.
[Footnote AC: Vide _Galilæo_]
[Footnote AD: Betwixt the Sword and Girdle of _Orion_.]
[Footnote AE: Vide _Reitha_.]
This, tho' I presume to call it at present only meer Hypothesis,
will in a great measure account for the excessive Changes in the
Constitution of our Air and Atmosphere, which we often find very
unnatural to the Season; also be a Means perhaps of reconciling
the vast Disproportion so very remarkable betwixt the Sun and the
lesser Planets, and many other Circumstances in the System of no
small Consequence in Astronomy: One of which Particulars you have
frequently expressed a great Mistrust and Disapprobation of, as
suspecting some kind of a Fallacy in the Computation; and the other
is Matter of general Complaint, being by many attributed to a Change
in the Direction of the Earth's Axis[AF]; and by some, especially the
Vulgar, to too near an Approximation of the Earth to some one of the
celestial Bodies. But all this will very naturally be accounted for
by the Levity, or expanding Quality of the Sun's circumambient Flame,
or Atmosphere; and hence, according to its various State, being more
condensed, or rare, we may have Heat or Cold in the greatest Extream,
and alternately so, in a perpetual Vicissitude.
[Footnote AF: Which, through Ignorance of the true Case, is commonly
called a Shock, a Brush, or Shove.]
The Truth of this Doctrine will evidently appear from the Observations
of the Sun's Diameter through the Year 1660, by the indefatigable
_Mouton_: And, I must own, I am not a little surprized to find that no
Conclusions have been drawn from them of this Kind. I am perswaded, if
you once compare those Numbers, you will be very far from thinking this
an improbable Suggestion. But this Digression has led me a little too
far from the _Via Lactea_, and too near home again; I must now think
of returning to the Stars, and my next Endeavours must be to give you
some Idea of the Number of them. Through very good Telescopes there
have been discovered in many Parts of this enlightened Space, and even
out of it, several thousand Stars in the Compass of one square Degree;
in particular near the Sword of _Perseus_, and in the Constellations of
[AG]_Taurus_ and _Orion_.
[Footnote AG: _Galilæo_ in one cloudy Star of this Constellation,
discovered no less than twenty-one, and in that of the _Præsepe_
thirty-six.]
PLATE XV.
Represents the _Pleides_, a well known Knot of Stars in the Sign
_Taurus_, as they appeared to me thro' a one Foot reflecting Telescope:
And _Plate_ XVI. is a View of the _Persides_, another surprizing Knot
of Stars in the Constellation _Perseus_, exactly as they appear through
a Tube of two convex Glasses. There are also other luminous Spaces
in the starry Regions, not unlike the Milky Way, which I have had
no Opportunity of observing; such as the _Nebeculæ_, near the South
Pole, called by the Seamen _Magellanic_ Clouds; and which likewise
viewed through Telescopes, present us with little _Nebulæ_, and small
Stars interspersed: One of these Kind is situated between _Hydrus_ and
_Dorado_; and another, something less than this, betwixt _Hydrus_ and
the _Toucan_.
Now admitting the Breadth of the _Via Lactea_ to be at a Mean but
nine Degrees, and supposing only twelve hundred Stars in every square
Degree, there will be nearly in the whole orbicular Area 3,888,000
Stars, and all these in a very minute Portion of the great Expanse
of Heaven. What! a vast Idea of endless Beings must this produce and
generate in our Minds; and when we consider them all as flaming Suns,
Progenitors, and _Primum Mobiles_ of a still much greater Number of
peopled Worlds, what less than an Infinity can circumscribe them, less
than an Eternity comprehend them, or less than Omnipotence produce and
support them, and where can our Wonder cease?
[Illustration: Plate XV.]
[Illustration: Plate XVI.]
In this Place perhaps I ought not to pass over the astonishing
Phenomenon of several new Stars, _&c._ which have frequently appeared,
and soon again vanished, in the same Point of the Heavens. But as
the Business of this Theory is rather to solve the general, than any
particular Phænomenon, I shall only here by way of Note subjoin a Table
of such as has been regularly observed, and by whom they were first
discovered.
_A Table of several new Stars_, Nebulæ, _and double Stars_, &c.
_Nomina Stellarum._ _Observationum._
_Septima Pleiadum_ { Lost after the burning of _Troy_,
{ but now returned; see
{ _Ricciolus_.
A new Star appeared in _Cassiopea_, } _Anno Dom._ 945, bright as
nearly in the same Place with that } _Jupiter_; see _Ricciolus_.
of 1572.
The new Star in _Cassiopea's_ Chair. { Bright as _Venus_, from _November_
{ 1572 to _March_ 1574.
{ Of the 3d Magnitude, is said to
A new Star in _Collo Ceti_. { have appear'd periodically, seven
{ Times in six Years, _i. e._ every
{ three hundred and thirteen Days:
{ It was first observed in _August_
{ 1596, for two Months, by _D.
{ Fabricius_.
{ Observed by _Kepler_ in 1600, of
A new Star in the Swan's Neck. { the third Magnitude, till the Year
{ 1659; then gradually decreasing;
{ in 1661 it disappeared; in 1666
{ it became visible again, and is
{ yet to be seen of the sixth
{ Magnitude.
A new Star in the Right Foot of { Bright as _Venus_ from _October_
_Serpentarius_, { 1604 to _October_ 1605: see
{ _Kepler_.
A new Star in _Andromeda's_ Girdle, { Seen by _Simon Marius_ and
{ _Fabricius_, _Anno_ 1612.
A new Star in _Antinous_, { Seen by _Justus Byrgius_.
{ In 1638, by _John Procyclides
A new Star seen in the Whale, { Holuarda_, of the third Magnitude,
{ which disappeared periodically,
{ every three hundred and thirty
{ Days.
{ Of the third Magnitude, seen by
A new Star in the Fox's Head, { _Hevelius_ in _July_ 1670, and
{ till _August_ 1671, also from
{ _March_ 1672 to _September_ 1672.
{ This appear'd periodically every
A new Star in the Swan's Neck. { four hundred and four Days, and
{ about six Months at a Time; it
{ was seen at its brightest,
{ _September_ 10, 1714.
_Of the_ Nebulæ, _or Cloudy Stars_.
_Nebulose_ in _Orion's_ Sword.
_Nebulose_ in _Andromeda's_ Girdle.
_Nebulose_ in the Bow of _Sagitarius_, Small, but very luminous.
_Nebulose_ in _Centaurus_, Never seen in _England_.
A _Nebulose_ preceding the right Foot } Obscure, but with a Star in the
of _Antinous_, } Middle of it.
_Nebulæ_ in _Dorso Herculis_, Discovered by Dr. _Hally_.
Besides the _Nebulæ_, and new Stars, it appears from the
ancient Catalogues of _Hevelius_, &c. that some of the old ones
have intirely vanished; in particular, one in the left Thigh
of _Aquarius_, the contiguous one preceding in the Tail of
_Capricorn_; the second on the Belly of the Whale; the first of the
unformed ones after the Scales of _Libra_, and several others. Many
of the Stars also appear to be double, as the first Star of _Aries_
and _Castor_; others triple, as one in the _Pleiades_; and the
middle one in _Orion's_ Sabre; and others again, quadruple, _&c._
I would now willingly help you to conceive the indefinite mutual
Distance of the Stars, in order to give you some small Notion of the
Immensity of Space; but as this will be a Task merely conjectural, I
shall only desire you to believe it as far as your Reason will carry
you, safely supported by an obvious Probability.
Perhaps it may be necessary here to acquaint you, that all the Stars
are so far apparently of different Magnitudes, that no two of them are
to be found in the whole Heavens exactly the same, either in Bigness or
Brightness[AH]. The largest we have sufficient Reason to believe is the
nearest to us; the next in Bigness and Brightness more remote; and so
on to the least we see, which we judge to be the most remote of all.
The first Degree, or that of the largest Magnitude, we give to Syrius,
the second to Arcturus, the third to Aldebaran, the fourth to Lyra,
the fifth to Capella, the sixth to Regulus, the seventh to Rigel, the
eighth to Fomahaunt, and the ninth to Antarus: These are all said to be
of the first Class; and besides which, there are at least, within the
Reach of our latest improved Opticks, nine more Denominations within
the Radius of the visible Creation.
[Footnote AH: A very little Knowledge in Opticks will render this
indisputable, and has been in a great measure demonstrated before;
1. in the Great Dog; 2. in Bootes; 3. in the Bull; 4. in the Harp of
_Apollo_; 5. in _Auriga_; 6. in the Lion; 7. in _Orion_; 8. in the
Southern Fish; 9. at the End of _Erridanus_.]
Now, by the certain Return of the Comets, which we find are all
governed by the Laws of this System, and supposed to be undisturbed
by any of the others, we cannot avoid concluding, if we consider them
at all to the Purpose, that the nearest Stars cannot be less distant
than twice the Radius of the greatest Orbit belonging to the Sun. Most
Mathematicians think this a great deal too near, as it must of course
make all the Systems join, as in Contact; and I think we may safely
add, to separate their Spheres of Attraction, at least one Half of
this Distance more, which will make in the Whole about four hundred
and twenty Semi-orbits of the Earth, or 33,600,000,000 Miles. This
even the ingenious Mr. _Huygins_ endeavours to prove still much too
little, and his Arguments are such as cannot easily be refuted. His
Principle is grounded upon the known Laws of Analogy, as considered in
the Proportion of light Surfaces, and is as follows. Having reduced
the Sun's Disk to the Appearance of the Star Syrius, by the Help of
a small Hole at the End of his Telescope, and comparing this Part of
his Surface to the whole Disk of the Sun, he infers that the Stars
Distance to that of the Sun must be as 27,664 to 1. Hence _Syrius_
from us will be nearly (avoiding Units) 2,213,120,000,000 Miles: But
this I take to be as much too large as the former is too little; yet,
as Mr. _Bradley_ has, with some Shew of Reason, banished all the
Stars out of the Sphere of Parallax, the last is the only Method we
can possibly make use of with any kind of Confidence; and Sir _Isaac
Newton_ endeavours to recommend it with great Force of Argument, as the
only probable Means by which we can give any tolerable Guess at these
immense Measurements of Space.
To moderate the Matter then if you please, allow me but to make use of
a Mean betwixt the two fore-mentioned Numbers; and we may take it for
granted, a Distance sufficiently exact, to suit all our Wants in the
present Case, namely, to give a very tolerable Idea of the Extent of
the visible Creation, which is all I propose in this Place to attempt;
but I mean to be much more exact in another.