AN IMPROVED APPARATUS FOR ILLUSTRATING THE MOTIONS OF SOME OF THE HEAVENLY BODIES AND EXPLAINING VARIOUS CELESTIAL PHENOMENA
Year: 1870

page_text: LETTERS PATENT to Henry Bryant, of Hartford, Connecticut, United
States of America, for the Invention of "AN IMPROVED APPARATUS
FOR ILLUSTRATING THE MOTIONS OF SOME OF THE HEAVENLY BODIES AND
EXPLAINING VARIOUS CELESTIAL PHENOMENA."
COMPLETE SPECIFICATION filed by the said Henry Bryant at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 30th May 1870, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
BRYANT, of Hartford, Connecticut, United States of America, send
greeting.
WHEREAS I am in possession of an Invention for "AN IMPROVED
APPARATUS FOR ILLUSTRATING THE MOTIONS OF SOME OF THE HEAVENLY BODIES
AND EXPLAINING VARIOUS CELESTIAL PHENOMENA," and have petitioned Her
Majesty to grant unto me, my executors, administrators, and assigns,
Her Royal Letters Patent for the same, and have made solemn Decla-
ration that I am the true and first Inventor thereof.

page_text: 66
"
by bringing it to cover any particular spot on the sphere the declination
and right ascension of that spot can be readily told off at sight. The
ball
g in the center represents the sun; h, h, the axis of the same; i, i,
the axis of the ecliptic; k, k, seen in dotted lines in Figure 2, the axis of
the heavens; all of these axes are attached together at the proper angle
of variation to each other, and the axes of the sun and of the heavens
turn about the poles of the ecliptic in bearings at i, . The letter
indicates the earth about which the moon m revolves. The other
planets o, o¹, 03, 0³, 0, 0, 0, and the asteroids indicated by the metal
plate marked 100 are attached to the wires n, n, n, n, n, n, n, n,
which
of proper lenghts to show their relative distances from the sun,
wires are inserted in disks 8, 8, 8, 8, 8, 8, 8, 8, and these disks are capable
of being revolved by an arrangement which will be more particularly
described herein-after. The wire ring - represents the moon's path
around the sun, and the shape of the whole ring is such and it is so
placed upon its supports r¹, 71, as to show the eccentricities of its path.
Attached to this ring are two flat plates of metal ³, ², to represent
the moon's nodes, and they are so engraved as to show where the paths
of the earth and moon about the sun intersect each other. The broad
metal band t represents the zodiac properly inclined to the plane of the
celestial equator; in the middle of the inside of the zodiac is marked the
line u to represent the ecliptic; the inside is also properly graduated to
show the twelve signs. The metal circle v fixed to the band c repre-
sents the path described by the revolution of the axis of the heavens
about the axis of the ecliptic and is graduated for the ready measure-
ment of this movement. The wire ring e which represents the celestial
equator is crossed at right angles by the wire ring w, which represents a
meridian, and the two are fastened together at the points of intersection,
and these two points of intersection represent the vernal and the autumnal
equinoxes. The wire ring w is fastened to the axis of the heavens at
the points where it intersects such axis. And when the pole of the
heavens represented in the Drawings as at c³ is revolved to the right or
westward the equinoxes will be seen to fall back on the ecliptic so as to
illustrate and explain the precession of the equinoxes, and this move-
ment also illustrates the motion of the celestial equator, thus changing
the declination of the stars.

page_text: The axis p is fastened rigidly into the sockets h¹, h¹; the disk x is
rigidly fastened to the shaft p, and has a shoulder upon its side upon
which the disk & supporting the moon's nodes turns; the other disks s, 8,
8, 8, 8, 8, 8, 8, turn upon the shaft p. The letter indicates a nut enclosing
the shaft p, and turning upon it with a screw thread at z¹ for turning
the nut up against the disks and fastening them in place. This nut
has a milled surface at for the thumb and finger, by which it can be
readily turned. Upon the opposite end of the shaft p from the nut z is
a thumb piece y operating similarly to the nut z, except that it has no
screw thread, and does not act as a tightener. Upon the side of the
disk x which is next the thumb piece y are two cams a¹ and a², the
former overlying the latter, and both equidistant from and upon opposite
sides of the center of the disk x; a collar b¹ which is a part of the
arm c¹ surrounds the cam a¹, and a collar 6³ which is a part of the arm c³
surrounds the cam a². These arms c¹ and c² lie in a slot in the disk
part of the thumb piece y, and as the thumb picce is rotated the arms
e and c² are carried around with it, and the effect of their attachment
to the cams a¹ and a² is such as to cause them to work out and in
alternately, the arm c¹ pushing out while the arm c² is retiring, and
vice versa.
Of course at two points in each revolution the arms (sup-
posing them to be of equal length) will protrude equally from the surface
of the sun g.
The end of the arm c³ supports one (the south) pole of the earth; the
bent end of the arm c¹ supports the opposite pole. The arm c³ contains
a revolving disk c³, to which is attached, at a distance from its center
corresponding to the action of the cams a¹ and a², by a headed screw pin
running through a slot in the arm the arm c¹.
And, now, supposing the earth to be at one of the equinoxes (see
Figure 3) and its axis to be parallel to the axis of the heavens, the action
of the whole device as the thumb piece y is rotated is to keep the poles
of the earth parallel to themselves at all times during a revolution around
the sun. By this device also the disk c³ is made to revolve backward,
causing the north pole of the earth to describe a small ellipse in a back-
ward direction from its direct motion, thus representing the earth's
nutation.
It will be observed that in the course of a revolution the arms c¹
and will reach two points familiarly known to mechanists as
" dead
centers," and this mechanical objection it is necessary to overcome.
It

page_text: 8. The combination of the shaft p, disk x, nut z, and the disks 8',
8, 8, 8, 8, 8, 8, 8, 8, substantially as and for the purpose set forth.
9. The combination of the shaft p, disk x, cams a¹, a², arms c¹, c³,
substantially as and for the purpose set forth.
10. The combination of the arms c³, c³, disk c³, cam v³, and spring &³,
substantially as and for the purpose set forth.
11. The combination of the shaft p, thumb piece y, disk x, cams a¹, a³,
and arms c¹, c³, substantially as and for the purpose set forth.
12. The arm m³ attached in the peculiar manner described to the
bent end of the arm c¹, substantially as and for the purpose set
forth.
13. The metal plates r³, ³, engraved as described for the purpose set
forth.
14. The ring combined with the supports 71, 71, and disk s¹, sub-
stantially as set forth.
15. The graduated circle combined with the ring c, substantially as
and for the purpose set forth.
16. The metal plates ³, 73, combined with the wire ring r, sup-
ports r¹, ¹, disk 8³, and disk x, substantially as and for the purpose set
forth.
In witness whereof, I, the said Henry Bryant, have hereunto set
my hand and seal, this Eleventh day of May, in the year of
our Lord One thousand eight hundred and seventy.
HENRY BRYANT. (L.S.)