Myths and Marvels of Astronomy
Egypt, and commenced the first dynasty of Misraimitish princes, who
excelled as cabalists, diviners, and in the mystic arts generally. The
most celebrated of the race were Naerasch, who first represented by
images the twelve signs of the zodiac; Gharnak, who openly described the
arts before kept secret; Hersall, who first worshipped idols; Sehlouk,
who worshipped the sun; Saurid (King Saurid of Ibn Abd Alkohm's
account), who erected the first pyramids and invented the magic mirror;
and Pharaoh, the last king of the dynasty, whose name was afterwards
taken as a kingly title, as Caesar later became a general imperial title.
[27] It is noteworthy how Swedenborg here anticipates a saying of
Laplace, the greatest mathematician the world has known, save Newton
alone. Newton's remark that he seemed but as a child who had gathered a
few shells on the shores of ocean, is well known. Laplace's words, '_Ce
que nous connaissons est peu de chose; ce que nous ignorons est
immense_,' were not, as is commonly stated, his last. De Morgan gives
the following account of Laplace's last moments, on the authority of
Laplace's friend and pupil, the well-known mathematician Poisson: 'After
the publication (in 1825) of the fifth volume of the Mecanique Celeste,
Laplace became gradually weaker, and with it musing and abstracted. He
thought much on the great problems of existence, and often muttered to
himself, "_Qu'est-ce que c'est que tout cela!_" After many alternations
he appeared at last so permanently prostrated that his family applied to
his favourite pupil, M. Poisson, to try to get a word from him. Poisson
paid a visit, and after a few words of salutation, said, "J'ai une bonne
nouvelle a vous annoncer: on a recu au Bureau des Longitudes une lettre
d'Allemagne annoncant que M. Bessel a verifie par l'observation vos
decouvertes theoriques sur les satellites de Jupiter." Laplace opened
his eyes and answered with deep gravity. "_L'homme ne poursuit que des
chimeres._" He never spoke again. His death took place March 5, 1827.'
[28] The reason assigned by Swedenborg is fanciful enough. 'In the
spiritual sense,' he says, 'a horse signifies the intellectual principle
formed from scientifics, and as they are afraid of cultivating the
intellectual faculties by worldly sciences, from this comes an influx of
fear. They care nothing for scientifics which are of human erudition.'
[29] Similar reasoning applies to the moons of Jupiter, and it so
chances that the result in their case comes out exactly the same as in
the case of Saturn; all the Jovian moons, if full together, would
reflect only the sixteenth part of the light which we receive from the
full moon. It is strange that scientific men of considerable
mathematical power have used the argument from design apparently
supplied by the satellites, without being at the pains to test its
validity by the simple mathematical calculations necessary to determine
the quantity of light which these bodies can reflect to the planets
round which they travel. Brewster and Whewell, though they took opposite
sides in the controversy about other inhabited worlds, agreed in this.
Brewster, of course, holding the theory that all the planets are
inhabited, very naturally accepted the argument from design in this
case. Whewell, in opposing that theory, did not dwell at all upon the
subjects of the satellites. But in his 'Bridgewater Treatise on
Astronomy and General Physics,' he says, 'Taking only the ascertained
cases of Venus, the Earth, Jupiter, and Saturn, we conceive that a
person of common understanding will be strongly impressed with the
persuasion that the satellites are placed in the system with a view to
compensate for the diminished light of the sun at greater distances.
Mars is an exception; some persons might conjecture from this case that
the arrangement itself, like other useful arrangements, has been brought
about by some wider law which we have not yet detected. But whether or
not we entertain such a guess (it can be nothing more), we see in other
parts of creation so many examples of apparent exceptions to rules,
which are afterwards found to be capable of explanation, or to be
provided for by particular contrivances, that no one familiar with such
contemplations will, by one anomaly, be driven from the persuasion that
the end which the arrangements of the satellites seem suited to answer
is really one of the ends of their creation.'
[30] The reader who cares enough about such subjects to take the
necessary trouble, can easily make a little model of Saturn and his ring
system, which will very prettily illustrate the effect of the rings both
in reflecting light to the planet's darkened hemisphere and in cutting
off light from the planet's illuminated hemisphere. Take a ball, say an
ordinary hand-ball, and pierce it through the centre with a fine
knitting-needle. Cut out a flat ring of card, proportioned to the ball
as the ring system of Saturn to his ball. (If the ball is two inches in
diameter, strike out on a sheet of cardboard two concentric circles, one
of them with a radius of a little more than an inch and a half, the
other with a radius of about two inches and three-eights, and cut out
the ring between these two circles.) Thrust the knitting-needle through
this ring in such a way that the ball shall lie in the middle of the
ring, as the globe of Saturn hangs (without knitting-needle connections)
in the middle of his ring system. Thrust another knitting-needle
centrally through the ball square to the plane of the ring, and use this
second needle, which we may call the polar one, as a handle. Now take
the ball and ring into sunlight, or the light of a lamp or candle,
holding them so that the shadow of the ring is as thin as possible. This
represents the position of the shadow at the time of Saturnian spring or
autumn. Cause the shadow slowly to shift until it surrounds the part of
the ball through which the polar needle passes on one side. This will
represent the position of the shadow at the time of midwinter for the
hemisphere corresponding to that side of the ball. Notice that while the
shadow is traversing this half of the ball, the side of the ring which
lies towards that half is in shadow, so that a fly or other small insect
on that half of the ball would see the darkened side of the ring. A
Saturnian correspondingly placed would get no reflected sunlight from
the ring system. Move the ball and ring so that the shadow slowly
returns to its first position. You will then have illustrated the
changes taking place during one half of a Saturnian year. Continue the
motion so that the shadow passes to the other half of the ball, and
finally surrounds the other point through which the polar needle passes.
The polar point which the shadow before surrounded will now be seen to
be in the light, and this half of the ball will illustrate the
hemisphere of Saturn where it is midsummer. It will also be seen that
the side of the ring towards this half of the ball is now in the light,
so that a small insect on this half of the ball would see the bright
side of the ring. A Saturnian correspondingly placed would get reflected
sunlight from the ring system _both by day and by night_. Moving the
ball and ring so that the shadow returns to its first position, an
entire Saturnian year will have been illustrated. These changes can be
still better shown with a Saturnian orrery (see plate viii. of my
Saturn), which can be very easily constructed.
[31] Not 'of course' because Tycho used it, for, like other able
students of science, he made mistakes from time to time. Thus he argued
that the earth cannot rotate on her axis, because if she did bodies
raised above her surface would be left behind--an argument which even
the mechanical knowledge of his own time should have sufficed to
invalidate, though it is still used from time to time by paradoxers of
our own day.
[32] Chinese chronicles contain other references to new stars. The
annals of Ma-touan-lin, which contain the official records of remarkable
appearances in the heavens, include some phenomena which manifestly
belong to this class. Thus they record that in the year 173 a star
appeared between the stars which mark the hind feet of the Centaur. This
star remained visible from December in that year until July in the next
(about the same time as Tycho Brahe's and Kepler's new stars, presently
to be described). Another star, assigned by these annals to the year
1011, seems to be the same as a star referred to by Hepidannus as
appearing A.D. 1012. It was of extraordinary brilliancy, and remained
visible in the southern part of the heavens during three months. The
annals of Ma-touan-lin assign to it a position low down in Sagittarius.
[33] Still a circumstance must be mentioned which tends to show that the
star may have been visible a few hours earlier than Dr. Schmidt
supposed. Mr. M. Walter, surgeon of the 4th regiment, then stationed in
North India, wrote (oddly enough, on May 12, 1867, the first anniversary
of Mr. Birmingham's discovery) as follows to Mr. Stone:--'I am certain
that this same conflagration was distinctly perceptible here at least
six hours earlier. My knowledge of the fact came about in this wise. The
night of the 12th of May last year was exceedingly sultry, and about
eight o'clock on that evening I got up from the tea-table and rushed
into my garden to seek a cooler atmosphere. As my door opens towards the
east, the first object that met my view was the Northern Crown. My
attention was at once arrested by the sight of a strange star outside
the crown' (that is, outside the circlet of stars forming the diadem,
not outside the constellation itself). The new star 'was then certainly
quite as bright--I rather thought more so--as its neighbour Alphecca,'
the chief gem of the crown. 'I was so much struck with its appearance,
that I exclaimed to those indoors, "Why, here is a new comet!'" He made
a diagram of the constellation, showing the place of the new star
correctly. Unfortunately, Mr. Walter does not state why he is so
confident, a year after the event, that it was on the 12th of May, and
not on the 13th, that he noticed the new star. If he fixed the date only
by the star's appearance as a second-magnitude star, his letter proves
nothing; for we know that on the 13th it was still shining as brightly
as Alphecca, though on the 14th it was perceptibly fainter.
[34] The velocity of three or four miles per second inferred by the
elder Struve must now be regarded (as I long since pointed out would
prove to be the case) as very far short of the real velocity of our
system's motion through stellar space.
[35] M. Cornu's observations are full of interest, and he deserves
considerable credit for his energy in availing himself of the few
favourable opportunities he had for making them. But he goes beyond his
province in adding to his account of them some remarks, intended
apparently as a reflection on Mr. Huggins's speculations respecting the
star in the Northern Crown. '_I_,' says M. Cornu, 'will not try to form
any hypothesis about the cause of the outburst. To do so would be
unscientific, and such speculations, though interesting, cumber science
wofully.' This is sheer nonsense, and comes very ill from an observer
whose successes in science have been due entirely to the employment of
methods of observation which would have had no existence had others been
as unready to think out the meaning of observed facts as he appears to
be himself.
[36] The same peculiarity has been noticed since the discovery of the
dark ring, the space within that ring being observed by Coolidge and G.
Bond at Harvard in 1856 to be apparently darker than the surrounding
sky.