A NEW OR IMPROVED INSTRUMENT FOR INDICATING ANGLES OR VARIATIONS OF LEVEL, AND FOR MEACHDING HORIZONAT A
Year: 1862

page_text: LETTERS PATENT to Jules Lefebvre, of 54, Rue des Tournelles, Paris,
in the Empire of France, Architect, for the Invention of "A NEW OR
IMPROVED INSTRUMENT FOR INDICATING ANGLES OR VARIATIONS OF LEVEL, AND
FOR MEACHDING HORIZONAT A D
35
Sealed the 28th April 1863, and dated the 4th November 1862.
PROVISIONAL SPECIFICATION left by the said Jules Lefebvre at the Office
of the Commissioners of Patents, with his Petition, on the 4th November
1862.
-I, JULES LEFEBVRE, of 54, Rue des Tournelles, Paris, in the Empire of
France, Architect, do hereby declare the nature of the said Invention for
"A NEW OR IMPROVED INSTRUMENT FOR INDICATING ANGLES OR VARIATIONS OF
LEVEL, AND FOR MEASURING HORIZONTAL AND VERTICAL DISTANCES," to be as
follows:-
I propose to call the instrument made in accordance with my Invention a
clitographe;" such instrument consists of a frame, which I prefer to make in
iron or other metal, by preference of a parallelogram shape. The frame has
suspended from the centre of its upper side a pendulous arm or radial bar, to
which a spirit level is attached at about the centre of its length, and so
mounted as to be readily capable of adjustment and rectification. A line
should be drawn vertically along the centre of the pendulous arm. At the
lower part of the frame there may be either one, two, or more sectors, on which

page_text: there is engraved at the centre of their length a zero point, and the angles are
marked right and left thereon, either as tangents or degrees and minutes, so
that all angles, abscisses, and ordinates can be readily read off. The pendulous
arm or radial bar may have a lip or guide piece at its lower end, working over
the bottom sector, so that it may be kept in position or up to its work; this
lip may form a vernier scale.
For use in the drawing office, workshop, and under similar circumstances,
as in setting up machinery or works of construction, the parallelogram-shaped
instrument only is necessary, but when it is intended to be employed by
surveyors for railway and road levelling, draining, and for other purposes, it
should be mounted upon a tripod, either by means of a frame surmounting a
telescope, into which the ordinary "clitographe" may be secured, or the
instrument may be so formed at its lower extremity as to receive a telescope,
and be pivotted upon a tripod stand.
The sectors may be divided decimally or duodecimally, or both divisions
may be employed by the use of two sectors so divided, or an additional sector
may be used for marking the degrees and minutes on the circumference.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Jules Lefebvre in the Great Seal Patent Office on the
4th May 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JULES
LEFEBVRE, of 54, Rue des Tournelles, Paris, in the Empire of France,
Architect, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of November, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Jules Lefebvre, Her special licence, that I, the said Jules Lefebvre, my
executors, administrators, and assigns, or such others as I, the said Jules
Lefebvre, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "A NEW OR IMPROVED INSTRUMENT
FOR INDICATING ANGLES OR VARIATIONS OF LEVEL, AND FOR MEASURING HORIZONTAL
AND VERTICAL DISTANCES," upon the condition, amongst others, that I, the

page_text: said Jules Lefebvre, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Jules Lefebvre, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement in writing, and accompanying Sheet of Drawings:-
A line should
At the lower
I propose to call the instrument made in accordance with my Invention a
"clitographe." Such instrument consists of a frame, which I prefer to make
in iron or other metal, by preference of a parallelogram shape. The frame
has suspended from the centre of its upper side a pendulous arm or radial bar,
to which a spirit level is attached at about the centre of its length, and so
mounted as to be readily capable of adjustment and rectification.
be drawn vertically along the centre of the pendulous arm.
part of the frame there may be either one, two, or more sectors, on which
there is engraved at the centre of their length a zero point, and the angles are
marked right and left thereon, either as tangents or degrees and minutes, so
that all angles, abscisses, and ordinates can be readily read off. The pendulous
arm or radial bar may have a lip or guide piece at its lower end, working
over the bottom sector, so that it may be kept in position or up to its work;
this lip may form a vernier scale.
For use in the drawing office, workshop, and under similar circumstances,
as in setting up machinery or works of construction, the parallelogram-shaped
instrument only is necessary, but when it is intended to be employed by
surveyors for railway and road levelling, draining, and for such other purposes,
it should be mounted upon a tripod, either by means of a frame surmounting
a telescope, into which the ordinary "clitographe" may be secured; or the
instrument may be so formed at its lower extremity as to receive a telescope,
and be pivotted upon a tripod stand.
The sectors may be divided decimally or duodecimally, or both divisions
may be employed by the use of two sectors, so divided, or an additional sector
5 may be used for marking the degrees and minutes on the circumférence.
The clitographies are instruments of precision, by which both vertical and
horizontal inclinations can be measured, the angles to be given either as
degrees of the circumference or as tangents, according to one or several units
of measure. By comparing the several scales (engraved twice, and in two

page_text: different directions from the zero point upon the vertical arc,) the clitographes
supply a table of natural tangents, and at the same time they instantly denote
the inclinations both in degrees and in units of measure. By means of these
instruments, therefore, the distances and altitudes can be obtained on the spot
without measurement, doing also away with the stations.
In the accompanying Sheet of Drawings I have shown my Invention
adapted to several purposes for which it may be employed.
Figure 1 is a view in front elevation of one class or description of
clitographe; Figure 2 is a horizontal section, taken on the line a, b, Figure 1;
Figure 3 is a transverse sectional view, taken on the line c, d; and Figure 4 is a
section taken on the line e, f. The sector D', shown in Figure 1, is graduated
or divided either decimally or duodecimally.
Figure 5 is a front elevational view of an arrangement of one of my
clitographes, provided with two scales (B and B"), the one being divided
decimally, and the other duodecimally, each of these latter scales being divided
into units and. fractions of lineal measurement in contradistinction to the
sector B, which is divided into minutes and degrees; Figure 6 is a longitudinal
section, taken on the line g, h, Figure 5; and Figure 7 is a vertical section,
taken on the line i, k, of Figure 5. It will be seen on reference to the two
last-named Figures that when it is required for the purpose of "sighting," a
telescope may be conveniently added.
Figure 8 is a front elevational view, showing an arrangement of one of my
clitographes, the framing of which is thin and flat on the face and edges,
instead of being wide and V-grooved (as in Figures 1 to 7), to allow of the
instrument being mounted on a rod or bar, as indicated by the dotted lines;
Figure 9 is a detached view of the top part of the framing of Figure 8, shewing
the method of adapting to this instrument an adjustable bar (G), and hinged
sight pieces (H); Figure 10 is a transverse section, taken through Figure 8,
on the line, m; Figure 11 is a section, taken on the line n, o, of Figure 9,
showing one of the sight pieces (H) opened out.
Figure 12 is a front elevational view of a similar class of instrument to that
illustrated by Figures 8 to 11; but instead of the bar and sight employed in
the last described variety of instrument, a telescope with adjustable movement
is substituted therefor, and a decimally or duodecimally divided scale B¹ is
added. This instrument may, as shown, be mounted by means of the bar Q
upon a tripod stand, and be provided with a horizontal circle, a compass and
the usual fittings to allow of its being used as a theodolite for the purposes of
horizontal surveying as well as levelling. Figure 13 is a transverse section
taken on the line p, q, of Figure 12.

page_text: Figure 14 is a view in front elevation of an arrangement of clitographe
specially designed and constructed to be used or employed for geodetical
operations upon a large scale. The instrument is shown as being mounted
upon a horizontal circle and tripod ready for use. The combination and
arrangement of scales and divisional parts employed is the same as that herein
before described when referring to Figures 5, 6, 7, &c.
In the Figures herein-before to, A is the spirit level; B, B', B, and B
the sectors, having scales divided thereon right and left of the zero point, in the
manner herein-before described; C; C, are the verniers, also having a zero
point marked thereon; D is the framing or support of the instruments, and
which in Figures 1 to 7 is shown as being formed with a V-groove E, round
the edges thereof, to allow of the instrument being readily placed on or against
any object, line or surface, for the purpose of taking the necessary observations
as to its coincidence with or its relation to or deviation from the true horizontal
or vertical line; F, (Figures 1 to 7) is the radially vibrating bar, having.
attached to it the spirit level A; F¹ is the radial arm or bar, as adapted to
the instruments, Figures 8 and 12, where it will be seen it is suspended in a
vertical position from the top of the frame of the instrument; F" is a portion
of the radial arm or bar in the arrangement shewn at Figure 9, to which, as
has herein-before been described, an adjustable bar G is adapted; H are the
sight pieces; J (Figures 5 and 6) is the pinion actuated by a thumb screw
and takes into a toothed segment K attached to the radial bar F, for the
purpose of enabling the same to be adjusted with exactitude; L is the pin or
pivot upon which the radial bar works; L' is a short tube or ferule, in which
the central pin or pivot L is enclosed and protected; M is the bar or rod upon;
which the instrument, shown at Figures 8 to 11 is mounted; and Q is the bar
or rod upon which the instrument shown at Figures 12 and 13 is attached, and
which is so formed as to allow of its being mounted upon a tripod stand; O is
the telescope in the variety of instruments illustrated by Figures 6 and 7, and at;
Figures 12 to 14. The instrument illustrated at Figure 14 is mounted upon a
tripod specially adapted for the support of this class or variety of my clitographes;:
the tripod being furnished with supporting screws; and a horizontal circle and
compass, and the other necessary fittings are added to allow of the instrument.
so arranged being used for all the purposes of levelling and surveying.
Figure 15 represents a form of " tripod," which from its simplicity, steadiness,:
and cheapness is specially adapted for the support of clitographes, but which
may also be used for other purposes.
Figure 16 is another arrangement of tripod stand, which is better suited for
carrying the larger and more delicate instrument for surveying and levelling..

page_text: In each tripod the legs are capable of being turned up or reversed when out
of use, for the purpose of protecting the metal pivot or stand of the instrument.
Heretofore, simple "levels" and "plumb rules," and squares, and frames of
wood and metal, have been employed for taking variations from the horizontal
and vertical lines by means of a "plumb" and line. The accuracy of the
indication depending upon the freedom of action of the "plumb" line; but,
by my Invention of clitographes, a rigid bar, either vertical or horizontal, is
employed in conjunction with a spirit level, and also simple or compound scales,
with one or more kinds or systems of divisions, by which the angles of deviation,
in portions of seconds and minutes, as well as the number of inches or parts of
inches of ordinate for each foot of abscissa, or any other relation of proportion
may be combined and indicated upon the face of the instrument, and each part
of the instrument subject to variation or motion, is capable of adjustment, and
each instrument is capable of several useful applications. The scales, as well
as the radial bars supporting the levels denoting the inclinations, may be placed
vertically or horizontally in the rectangular frames of the instruments, accord-
ing to the purposes for which the instrument may be most generally required.
The rectilinear, graduation, or tangent lines can be engraved, either on a straight
line to be subdivided by means of a vernier, or on a curve, along which an
indicator only without a vernier, may be moved.
By the use of these instruments, the results are read off upon the scales at
once, without the necessity for calculations, and the verification of the work can
be immediately effected by reversing the instrument and taking the mean of
the two readings; the divisions on each scale or sector being double from the
zero point. The advantage of the V-shaped groove surrounding the frame, is
that of enabling the instrument to adjust itself truly against a fillet, straight-
edge, or other projection, or along the axis of a shaft, and thus the instrument
may be employed for levelling, in draining land, in combination with a long
straight-edge or bar.
Figure 14 is a modification of the rectangular clitographe intended for
surveying and levelling only; and although the frame instead of being
rectangular is shewn as triangular, it may either be contained within a
rectangular frame, or be constructed as shewn, and in combination with a
horizontal dial or circle divided in a manner similar to the other instruments,
and where the distance of the object sighted is known, it has to be multiplied
by the tangent of the angular opening given on the horizontal circle, the
tangent itself being read from off the limb of the instrument.
As the mode of using such instruments will be readily understood by every
surveyor or other person conversant with the ordinary theodolite level, as in

page_text: use, it will be unnecessary to give herein any more detailed description of the
mode or method of applying the clitographes in practice.
Having now described my Invention, and illustrated the same by the several
views in the accompanying Drawings, I wish it to be understood that I do not
confine myself to the exact shape, dimensions, or proportions of the several
parts of the instruments herein described or shewn in the accompanying
Drawing, nor do I make any claim for the tripod stands, although they are
shewn at Figures 14, 15, and 16, as being simple, convenient, and cheap means
of supporting such instruments, neither do I make any claim for such parts of
the said instruments as are old or well known; but what I claim is,―
First, the combination of parts in the several modifications of clitographes
as shewn in the accompanying Drawing, and herein-before described.
Second, the combination of a rectangular frame, as described, with a radial
arm in combination with a spirit level, and a divided sector or sectors, and a
scale or scales as herein described, and as shewn in the accompanying Drawing
for the purpose of reading verticals and horizontals, or the variations from
vertical or horizontal lines.
In witness whereof, I, the said Jules Lefebvre, have hereunto set my
hand and seal, this Twenty-seventh day of March, One thousand eight
hundred and sixty-three.
JULES LEFEBVRE. (L.B.)