AN IMPROVED APPARATUS FOR EXHIBITING TO THE EYE THE ROTATION of THE EARTH AROUND ITS AXIS
Year: 1878

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"AN IMPROVED APPARATUS FOR EXHIBITING TO THE EYE THE ROTATION of
THE EARTH AROUND ITS AXIS." A communication from abroad by Charles
Mancel de Perceval, of the City and State of New York, United States of
America.
Sealed the 16th July 1878, and dated the 17th January 1878.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at
the Office of the Commissioners of Patents on the 17th January 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "AN IMPROVED APPARATUS FOR EXHIBITING TO
THE EYE THE ROTATION OF THE EARTH AROUND ITS AXIS." [A communication from
abroad by Charles Mancel de Perceval, of the City and State of New York, United
States of America.]
This Invention is based upon the principle or law that the oscillations of a
pendulum suspended above a point on the earth, and commenced in any vertical
plane intersecting that point will continue in the same vertical plane.
&
In applying this law for the purposes of the said Invention, I cause
pendulum to be suspended at a point about two hundred feet from the weight or
bob of the same, which must be done in a tower or building suitable for the
purpose.
The part of the pendulum rod which extends below the weight or bob, or a
suitable projecting stud, is made to oscillate within a longitudinal groove or slot in
a frame placed underneath the said weight. This frame, which I call a supporter,
rests upon a globe or map of the earth at a point directly under the centre of motion
of the pendulum, and is there connected with the pole of the globe by a vertical
joint, so that the globe can rotate without any movement of the said supporter.
Extending from the latter down over the surface of the globe are arms or indicators,

page_text: some of which extend to points above the equatorial line, and others below that line.
The lower ends of all these indicators are arranged to point to any desired locality
upon the earth's surface as represented upon the globe.
It is obvious that as the pendulum always performs its oscillations in the same
vertical plane, the said frame or supporter will always be held in that plane by the
oscillations of the said pendulum rod extension or stud within the groove or slot in
the said supporter, and consequently the said indicators being fixed to the said
frame or supporter must remain fixed, and will not partake of the motion of the
earth.
The earth rotates from west to east, and of necessity carries with it the globe or
map in the same direction, and also the tower and the spectators with the velocity
of the earth's rotation; but the indicators, from their being constantly fixed by the
oscillations of the pendulum within the said groove, mark an increasing distance
from any locality as a starting point from east to west, and thus is exhibited visibly
the earth's rotation upon its axis.
To further carry out the object of the said Invention I place upon the equatorial
line a fixed ring which is provided with cogs or teeth forming a rack, the said longer
indicators are provided with hands or pointers which are jointed to the said
indicators close to the said equatorial ring, and they are provided with pinion wheels,
the teeth of which gear into the teeth of the said ring, so that as the globe and ring
rotate with the earth, the pointers revolve upon the centres of their pinions, and
their revolutions when made to perform within any given time will mark the distance
run by the surface of the earth in its rotation, and the time of running such distance
at the latitude of the spectator.
Thus by means of the said Invention the rotation of the earth is made visible to
the eye at any desired locality, and the distance run by the earth's surface upon the
degree of latitude of such locality is measured by the pointers visibly to the eye of
the spectator.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Robert Lake in the Great Seal Patent Office on the 17th
July 1878.
"
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. AN IMPROVED APPARATUS FOR EXHIBITING TO
THE EYE THE ROTATION OF THE EARTH AROUND ITS AXIS." A communication from
abroad by Charles Mancel de Perceval, of the City and State of New York, United
States of America.
This Invention is based upon the principle or law whereby the oscillation of a
pendulum suspended above a point on the earth, and commenced in any vertical
plane intersecting this point is caused to continue in the same vertical plane.
In applying this law for the purpose of the said Invention I cause a pendulum
to be suspended at a point about two hundred (200) feet from the weight or bob in
a suitable tower or building, as in Figure 1 of the accompanying Drawing, which shews
the said apparatus in elevation.
:
The part of the pendulum rod a below the weight or bob b, or a suitable projecting
stud c as the pendulum oscillates, is moved to and fro within a longitudinal groove
or slot in a frame d underneath the weight b. This frame d, which I call a supporter,
rests upon a globe e or map of the earth at a point directly under the centre of motion
of the pendulum, and is there connected with the pole of the globe by a vertical
joint, so that the globe can rotate without any movement of the said supporter.
From the latter arms or indicators f, g, extend down over the surface of the globe. The
arms f extend to points above the equatorial line h, and the arms g extend below
that line as shewn. The lower ends of all these indicators are arranged to point to
any desired locality upon the earth's surface as represented upon the globe e.
It is obvious that as the said pendulum performs all of its oscillations in the same
vertical plane, the frame or supporter d will always be held in that plane by the
stud c moving to and fro within the said groove or slot, and consequently the
indicators f, g, being fixed to the frame or supporter d, must remain in the same
position, and will not partake of the motion of the earth.
The earth rotates from west to east, and of necessity carries with it the globe or
map in the same direction, and also the tower and the spectators with the velocity
of the earth's rotation; but the indicators, by reason of their being kept in one
position during the oscillation of the pendulum by the movement of its slide within
the said groove, will mark an increasing distance from east to west from any locality
or position used as a starting point on the globe, and in this manner the earth's
rotation upon its axis as visibly shewn.
To further effect the object of the said Invention I place upon the equatorial line
a fixed ring, which is provided with cogs or teeth forming a rack. The said long
indicators gare provided with hands or pointers h¹ which are jointed to the said
indicators close to the equatorial ring, and provided with pinions which gear with
the toothed ring or rack, so that as the globe and ring rotate with the earth, the
said pointers revolve upon the centres of their pinions, and their revolutions within
any given time will mark the distance of movement of the surface of the earth in
its rotation, and the time of moving through this distance at the latitude of the
spectator.
Thus by my Invention the rotation of the earth is made visible to the eye at any
desired locality, and the distance of movement of the earth's surface upon the degree
of latitude of such locality is measured by the pointers visibly to the eye of the
spectator.
I term this improved apparatus for demonstrating or exhibiting the earth's motion
"the geoscope."
Figure 2 represents my improved apparatus or "geoscope" as constructed more
especially for sahnala

page_text: base A and one in the pendulum ball; the globe and the two.columns or bars B are
fixed to a plate C which is placed on the base and turns thereon, at the same time
the pendulum oscillates in the groove of the supporter d, keeping it and the
indicators f, g, steady; the ring or rack gears with the pinions and the hands h¹
(which are fixed on the indicators g, g.) and makes them turn to indicate a certain
number of miles travelled by the earth's surface at the equator. Although the point
of suspension of the pendulum turns, the pendulum will not change its plane of
oscillation.
When my improved apparatus or "geoscope" has a long pendulum the motion of
the earth takes the place of the clockwork in the base, and the pendulum does not
need any motive power.
"
Figure 3 represents an apparatus which I term a geoscope-clock." The dial
can be placed either on the top or in the pendulum-ball, or as shewn; a statue
may be substituted for the bars and top for supporting the pendulum.
In Figure 4 I have shewn my Invention constructed as a toy to be worked by
hand.
Having thus fully described the said Invention, as communicated to me by my
I wish it understood
foreign correspondent, and the manner of performing the same,
that I claim,-
First. The apparatus consisting of the pendulum, the grooved or slotted frame or
supporter, and a globe or map representing the surface of the earth, combined and
operating as above set forth and for the purpose specified.
Second. The combination of the pendulum, the supporter, and the indicators, as
above set forth and for the purpose specified.
Third. The combination of the pendulum, the frame or supporter, the indicators,
and the ring or rack with the pinions and hands or pointers, constructed and
operating as above set forth and for the purpose specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Seventeenth day of July, in the year of our Lord Ono
thousand eight hundred and seventy-eight.
M RORT LAKE
Ta