, 1880-05-03
The Earth in Miniature.


Many persons have seen the some
what clumsy apparatus known as the
plaDetarium or orrery, the purpose of
which is to show the arrangement of
the solar system and the motions of the
planets around the sun. The best of
these are rude, and from their quite
apparent machinery of rods and wires
are apt to be misleading to the young
and untutored. "We have Just seen
an invention" says the London Times,
(which, for want of better name, we
must call planetarium, but which,
though intended to eubserve the same
purpose, has but little in common with
the old-fashiored apparatus. This in
vention is the work of an Italian, Sig
nor N. Perrin, long resident in Lon
don, and whose name is, no doubt, ia
miliar to some of our civil service and
military readers as a successful teach
er. The new planetarium is erected in
the midst of an ordinary y-sized rom,
with a ceiling higher than usual. On
entering the room one sees a high Cir
cular chamber, or box, standing on
twelve wooden pillars. On entering
underneath this chamber, and looking
up, dome is seen. deep blue, and
sprinkled with stars, the chief northern
consultations being in their proper
places, and round the base of the dome
the names of the signs of the zodiac. Pen
dant from the top of the dome by mar
row tube is an opal globe, lit inside by
gas, and representing the sun. From
wires, almost invisible, the planets are
suspended around the sun, OF sizes
and at distances approximately proper
tionate to the real sizes and distances,
and each having its proper inclination
to the plane of its orbit. The various
moons are in their places and Saturn
has his rings. The general effect on
looking up at this arrangement from
below is impressive, and this effect is
increased when Signor Perrin, by sim
ply turning key, sets the system ia
motion, rapid or slow, as he chooses.
The sun turns on his axis, and the
planets in their orbits, all in time ac
curately proportionate, and on watch
ing the movements for a short time
one easily realizes the immense differ
ences in length of the years of the
earth and those of the outer planets.
By an ingenious watchwork arrange
ment inside the earth, which is the
size of a walnut, our world is made to
revolve on its axis, the latter, by
special effort of ingenuity of Signor
Perini, being always made to point to
the same quarter of the heavens. The
same arrangement causes the moon to
revolve round the earth in its own
proper orbit. Perhaps the great tri-
umph of this invention is the fact that
the planets revolve round the sun in
proper elliptical orbits, which are
traced around the inside of the dome.
The dome is IA feet IN diameter at its
base and IA feet high. In the cham
ber above the dome the machinery in'
vented by Signor Perrin is arranged.
the details being as yet secret. The
moving power is clockwerk, the origi-
nality in the arrangement being, we
believe, the method by which the in
ventor effects the elliptical motion of
the planet. Not a sound is heard
when the machinery is in motion. the
whole working IN that "solemn 81
lence" which the hymn tells us is
characteristic of the starry sky. The
inventor could, We believe, make his
planetarium of any size, from the dome
of st. Pauls to a little thing that
might be used for school instruction.
Signor Perrin has devoted his nights
and mornings to this structure for
seven years, and has expended upon it
something like So, 500; the earth itself,
Ill, l.
believe he has been prompted to this
work solely by the enthusiasm of n
mechanician, and by desire to do
something to enable those interested in
astronomy to realize, as far as possible,
the arrangements of the solar system.
We may say that it is almost impossi-
BILE to put it out of order, and it can be
taken to pieces in very short time.
His address is Garrick Chambers, Gar
rick street.