Improvements in Armillary Spheres.
Year: 1895

page_text: Date of Application, 2nd Feb., 1895-Accepted, 13th July, 1895
COMPLETE SPECIFICATION.
Improvements in Armillary Spheres.
I SYLVESTER MINIER GIBBS, of Danville, in the County of Montour, and
State of Pennsylvania, United States of America, Schoolteacher, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
My invention relates to improvements in apparatus for illustrating to the eye the
relative, real and apparent, positions and movements of the earth, sun, moon, and
stars; the object of my invention being to exhibit accurately and truthfully and.
ellipticity of the earth's orbit and its position with relation to the sun, the latter
being located in one of the foci of the ellipse; the inclination of the earthi's axis
to the plane of the ecliptic, the parallelism of. the axis during the entire yearly
revolution, the changes of the axis and of the poles in their relations to the plane
of the ecliptic and the direction of the sun's rays north and' south of the equator,
before and after passing the equinoxes; the positions of the earth at the. vernal
and autumnal equinoxes, at summer and winter solstices, and' in perihelion and'
aphelion; the relative positions and apparent movement of the sun through the
constellations of the zodiac; the phenomena of eclipses, conjunctions, oppositions,
diurnal revolutions producing day and night, sunrise and sunset, the causes of the
constant change of the proportionate periods, in different regions, of the divisions
of time due to the diurnal revolutions, the seasons, the rising and setting of certain
stars and constellations, and the relation between the earth and' such stars and
constellations as are affected by the relative positions of the earth and the sun;
the equation of time; the modes and phases of the moon; the relation of the
plane of its orbit to that of the earth; the precession of the equinoxes or the
retrogression of the equinoctial points; to represent the systems of imaginary
circles in the sky by material rings, and to provide means whereby such circles,
and also the planes of the orbits of the moving celestial bodies may be adjusted to
represent their positions in the latitude of the observer.
Further objects and advantages of the invention will appear in the following
description and the novel features thereof will be particularly pointed out in the
appended claims.
In the drawings ;-
;-
Figure 1 is a perspective view of an armillary sphere embodying my
invention.
Figure 2 is a vertical section of the same.
Figure 3 is a view of an attachment designed to illustrate that the orbit of
the moon crosses and recrosses the orbit of the earth, that its motion is alternately
accelerated and retarded, according to the relative positions of the sun, earth and
moon, its motions being controlled jointly by the sun and earth, and that while
passing around the earth the moon does not retrace or move backward upon
its course.
Fig. 4 is a detail view of a portion of the band having the signs of the zodiac.
Fig. 5 is a detail view showing the pivotal connections of the rings representing
various celestial circles.
Similar numerals of reference indicate corresponding parts in all the figures of
the drawings.

page_text: The framework consists of a horizontal frame 1, preferably circular in form,
which is attached to the upper ends of the curved side bars 2, the lower ends of
said side bars being fitted in seats 3, formed in the facing or juxtaposed surfaces
of the parallel disks 4, which are held in their proper relative positions by means
of the vertical bolt 5. Three of these side-bars are preferably employed, and
between the planes thereof are formed, in the inner or facing surfaces of the
disks 4, the seats 6, in which are fitted the inner ends of the legs 7.
At opposite sides of the frame are arranged the horizontal pivot-screws 8, upon
which is mounted a circular band 9 representing the zodiac and constellations and
also pivotally mounted upon the same pivot screws are a ring 10, representing a
celestial or extended equator, a ring 11, representing the ecliptic rings 12 and 13
representing the orbit of the moon extended, and the prime vertical, and rings 14
and 15 representing the colures. Concentric with the pivot at one side of the
frame is a graduated indicator 16 upon which are inscribed angles to assist the
operator in adjusting the various rings etc., to suit the location of the supposed or
actual observer, all of which parts and adjustments are fully described in my said
former Patent.
One of the side bars of the framework is slotted as shown at 17, and in this
slot is fitted one end of a tubular bearing 18, having a fixed collar 19 to bear
against the inner surface of the side bar and a nut 20 threaded upon the outer
extremity of the bearing to bear against the outer side of the bar. A disk 21 is
attached to the outer projecting end of the bearing to indicate the positions of the
various solstices and equinoxes.
Mounted in the above-described bearing is a spindle 22, which carries a central
globe 23 representing the sun, and fixed to said spindle is a rotary frame 24,
having a ring 25 which is parallel with the orbit of the earth, and a series of radial
arms 26 which support said ring. Attached to this rotary frame is a swinging
arm 27 provided with a weight 28 to hold it in a pendent position, and rising in an
inclined position from the lower extremity of said arm is a spindle 29 upon which
is mounted a globe 30 representing the earth. Swiveled upon the upper portion
of the arm 27 is an auxiliary arm 31 which carries a globe 32 representing the
moon and removably attached to the surface of the globe 30 by means of a
pin 33 is a small disk 34 designed to represent the sensible horizon of an imaginary
observer.
Inferior planets are represented by the globes 35 and 36 having supporting
arms 37 and 38 provided at their inner ends with sleeves 39 and 40 which embrace
the spindle 22, aud are secured in the desired positions by means of set-screws 41
and 42, and a superior planet is represented by the globe shown at 43 which is
supported by the arm 44 secured to the tubular bearing 18.
The band 9 consists of an outer member 45 and an inner member 46, the outer
member having its lateral edges bent inward to form grooves 47 in which the
edges of the inner member fit slidably; the inner member being slotted as shown
at 48 to receive the pivot screws and being provided at diametrically opposite
points with knobs or buttons 49 to facilitate the turning of the inner member
within the outer. The object of this adjustment of the inner member of the band
with relation to the outer member is to illustrate the celestial variation known as
the precession of the equinoxes, but which more properly is the recession of the
equinoxes or the advance of the constellations.
The outer member of the band is provided with names of the twelve signs of
the zodiac, each sign occupying thirty degrees, and the inner or movable member
of the band is provided with a series of names representing the constellations. By
moving the inner band within the outer the relative positions of the constellations
and the various signs from the time of Hipparchus to the present day or within the
last two thousand years, may be illustrated.
In Fig. 3 I have illustrated a sinuous ring 50 designed to illustrate, in connection
with certain parts of the above described apparatus, the orbit of the moon.
Said
ring is adapted to be placed within the band representing the zodiac and against

page_text: the ring 12 which represents the extended orbit of the moon, as shown in said
Fig. 3, and although when in this position it is obvious that the rotary frame
carrying the globes representing the earth and moon cannot be rotated through a
complete circle sufficient motion can be given to illustrate this principle, namely:
that the moon passes around the earth and crosses its orbit that at certain times
it moves faster and at other times slower than the earth, but that it always moves
forward, and that its movements are controlled jointly by the earth and the sun.
It is obvious that owing to the small scale upon which the apparatus is constructed
and the necessary disproportionate sizes of the globes representing the various
celestial bodies with relation to their orbits the exact relative movements of the
moon and earth cannot be illustrated and the precise diagram of the orbit of the
moon cannot be given, for it is well known that the orbit of the moon does not at
any point present a convex side toward the sun, but at the same time it is evident
that certain other relations between the three bodies named that is the sun, moon
and earth, such as those above mentioned can be accurately illustrated, and made
visually apparent to the student. While it is possible at times to show these
features of the moon's relations to the earth and sun without the sinuous ring, I
have found it of value in connection with the other parts of the apparatus, as a
means of simplifying the illustration.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. In a device of the class described, the.combination with a supporting frame,
and means mounted therein for illustrating celestial phenomena, said means
including a rotary frame carrying a globe representing the earth, of a band
representing the zodiac mounted in the frame and comprising inner and outer
members, one of which is slidable upon the other, substantially as specified.
2. In a device of the class described, the combination with a supporting frame,
and means mounted therein for illustrating celestial phenomena, said means
including a rotary frame carrying a globe representing the earth, of a band
mounted in the supporting frame and encircling the rotary frame, the same com-
prising an outer member bearing the signs of the zodiac and an inner member
slidably mounted in the outer member and bearing the names of the constellations,
and means for turning the inner member within the outer member, substantially
as specified.
3. In an armillary sphere, the combination with a frame, a ring representing
the extended orbit of the moon, and a rotary frame carrying globes representing
the earth and moon, of a sinuous ring adapted to be arranged approximately in the
plane of said ring representing the extended orbit of the moon, substantially as
specified.
4. The combination with a central globe representing the sun, a ring repre-
senting the plane of the ecliptic, a globe representing the earth and means for
moving the same in a path parallel with the plane of the ecliptic, and a sinuous
ring adapted to be arranged at an angle to the plane of the ring representing the
ecliptic, substantially as specified.
Dated this 2nd dor of February 1805
BOULT & WADE,
Agents for the Applicant.