AN IMPROVED INSTRUMENT FOR MEASURING AND TRACING
Year: 1853

page_text: LETTERS PATENT to Jules Alexis Adrien Dumoulin, of Paris, in
the Empire of France, and of 16, Castle Street, Holborn, (City,)
London, for the Invention of "AN IMPROVED INSTRUMENT FOR
MEASURING AND TRACING."
Sealed the 16th December 1853, and dated the 16th June 1853.
PROVISIONAL SPECIFICATION left by the said Jules Alexis
Adrien Dumoulin at the Office of the Commissioners of Patents,
with his Petition, on the 16th June 1853.
I, JULES ALEXIS ADRIEN DUMOULIN, of Paris, in the Empire of
France, and of 16, Castle Street, Holborn, City, London, do hereby
declare the nature of the said Invention for "AN IMPROVED INSTRUMENT
FOR MEASURING AND TRACING."
My apparatus for measuring and tracing outlines in Figures 1,
and 2, of the Drawings. The apparatus is mounted on a slight iron
framework, itself resting on two wheels, of which the largest (C,) in
turning sets the whole mechanism in motion. The other wheel serves
only to support the apparatus, and keep it horizontal by means of a

page_text: pressing screw b. b. b. The plank D, D, is made fast to the frame.
An endless roll of paper surrounds the cylinder g, extends its whole
length on the plank D, D, to a pair of laminating cylinders a, a²,
of which the upper one presses on the lower one by means of a
spring,, which rests on a piece between these two cylinders;
it makes half a turn on the upper one, and rolls itself on a third
cylinder v, which rises as its diameter increases.
The principal wheel C, must have a diamater of 0.7958, and a
circumference of 2.50. This wheel transmits its motion by means
of two gearings, and the chain 7, 7, to the disc A, and the latter
transmits the motion in the same manner to the disc B.
10
The laminating cylinders are of the diameter of the driving
wheel C. So that, if between these cylinders and the axle h', ', of
the pulley H, of the disk A, a transmission gearing of 1 50 be placed,
the relative lengths of the turns of the wheel may be ascertained with
those of one of the cylinders of 1 500 proportionate parts. Near the
laminating cylinders is fixed a bar u, u, on which slide a certain
number of styles so arranged that they may mark so many lines of
comparaison at different heights.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Jules Alexis Adrien Dumoulin in the Great Seal
Patent Office, on the 16th December 1853.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
JULES ALEXIS ADRIEN DUMOULIN, of Paris, in the Empire of France,
and of 16, Castle Street, Holborn, (City,) London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of June, in the year
of our Lord One thousand eight hundred and fifty-three, in the six-
teenth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Jules Alexis Adrien Dumoulin, Her
special licence that I, the said Jules Alexis Adrien Dumoulin, my
executors, administrators, and assigns, or such others as I, the said
Jules Alexis Adrien Dumoulin, my executors, administrators, and

page_text: 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 "AN IMPROVED INSTRUMENT FOR
MEASURING AND TRACING," upon the condition (amongst others) that I,
the said Jules Alexis Adrien Dumoulin, by an instrument in writing
under my hand and seal, should particularly 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 Alexis Adrien Dumoulin,
do hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement (that is to say):
The theory of this machine is founded upon the following geome-
trical principles, shown in Plate I., proposition I.:-If on a tract of
land inclined to the horizon by any angle A, B, C, Fig. 1, a pendulum
or plumb line is left to the action of gravity, its line of suspension will
make, with the perpendicular a, b, dropped upon the ground, an angle
equal to the angle made by the ground itself with the horizon. Hence,
angle A, B, C, P, o, b; and if this pendulum carries a lever, in its
centre line produced, and another æ, making an angle of 90° with
it, for any line a, b, parallel to the ground, we shall have angle
|B, 0, ', A, B, C, = a, o,, = ', o, a, being vertical angles. From
this it is evident that whatever may be the inclination of the line a, b,
to the horizon, the angles b, 0, 2, and a', o, a, will always be comple-
ments to each other, and therefore sin. 6, 0,,cos. ', o, a, and
sin. a', o, a, cos. 6, 0,, and the same, vice versa, for any angle made
by the pendulum. Proposition II.:-Every circumference described
from centre o, Fig. 2, and passing through the point of intersection of
a sine or cosine of any angle with the radius is proportional to the part
of the radius between this point of intersection and the centre 9, this
part being in fact the radius itself of the circumference described,

page_text: and every circumference being proportional to its radius. Hence, from
the equality of sines and cosines proved in the preceding proposition
we have also (circumference a, corresponding to 15°): (sin. 15° 0, 1)
: (circumference e, corresponding to the angle 75° or—165°): (sin.
75°, or cos. 165 = 05). Thus we have for an angle of 30° made
by the pendulum, Fig. 7, (circumference v,): (w, v, = x,y,) : : (circum-
ference y,) (w, a,=,=). For an angle of 45°, Fig. 6, there is only
one circumference 1, 7, the sine and cosine being equal, as well as the
two angles.
We shall now consider the mechanical application of the pre-
ceding principle:-Let P, Fig. 3, be a heavy pendulum suspended
from a centre o, and branching off in two levers a,, which have
bearings c, c, respectively. These bearings are themselves capable
of sliding up and down in the vertical slot G, G, governed by the
levers a,, which follow the oscillating motion of the pendulum P.
The slides G, G, G, G', also follow the impulse of the pendulum
by describing a traversing motion in the direction of the guide rods
9, 9, 9, which form a frame fixed on the stands q, 7, 9, 4. The slides
have have each two arms K, K, K, K, whose extremities are bosses
tapped to receive steel screws i, i, i, i, turned to conical points.
Let there be two pulleys H, H, turning each on a shaft which has at
its end a worm gearing into a wheel n, driven by any circular motion.
These two pulleys are made to slide lengthwise on their shaft, whilst
they turn by means of a key moving in a groove h, h. Each of the
pulleys has a nick p, p, turned on its boss, which receives the conical
end of the screws i, i, t, i, so as to follow the traversing motion of the
guide rods G, G. Let A, B, also be two vertical discs moving in the
direction of the arrows with a uniform rotary motion. Each of these
dises being pressed against its respective pulley by a spring and centre
point. They will communicate to them motions varying with the inclina-
tion of the pendulum. Thus, in the normal position of the pendulum, as
is seen in Fig. 3, the pulley of the disc B, is placed on the centre w, and
is therefore at rest, whilst the pulley belonging to the disc A, is at its
greatest distance from the centre w, of the latter, and rolls upon the
greatest circumference f, f, which is equal to that of the pulley itself,

page_text: and thus the disc causes the pulley to describe as many revolutions as
itself, and these revolutions are all in one direction, on whichever side
the pendulum inclines. But if a quarter of a revolution is given to
the pendulum, the levers a, z, will then take the position indicated in
Fig. 4, and the pulley of the disc A, will be on the centre w, and at
rest, whilst that of B, will be on the maximum circumference f, f, and
make the same number of revolutions as the disc.
Let us place the pendulum now in the position corresponding to Fig. 5;
the pulley of the disc A, will again be in the centre and at rest, whilst the
pulley of the disc B, will revolve again with the same angular speed as
the disc on the same circumference ff, but on the opposite side, so that
the motion will be in a contrary direction, or negative.
In the position
corresponding to Fig. 6, the two pulleys are driven with equal speeds,
for they both roll on equal circumferences, i. c., the same 1, 1. In the
position shewn in Fig. 7, in which the pendulum makes an angle of
30°, the pulley of the disc A, will be placed on the circumference v, r',
and will receive a motion proportional to, w,=,y,= cos 30°; and
the pulley of the disc B, will roll on the circumference y, and receive a
motion proportional to w, y, v, a, sin 30°, 9, E, D). If these two
motions, being divided by a proper and constant gearing, i. c., reduced
so as to produce results on a given scale, are transmitted by the pulley
A, to an endless sheet of paper so as to give it a rectilinear motion in
the direction of its length, and by the pulley B, undergoing an equal
reduction of scale to a pencil moving in a direction perpendicular to
that of the paper, the line described by the pencil will be the resultant
of the two motions, i. e., it will be the continued hypothenuse of a series
of small triangles which are described by a corresponding series of oscil-
lations of the pendulum. Finally, this apparatus being properly fixed
on a small car, with two wheels carrying a little board on which
the paper unfurls, as is seen in Fig. 8, it is easy to conceive the exact-
ness and practical truth of the result promised by the title of my appa-
ratus, which I am going to describe now.
The apparatus, Plate II. bis, rests upon a light cast iron frame
F, F, F, on two wheels of which the larger C, acts as the prime mover
of the apparatus by rolling on the ground to be measured. The other

page_text: wheels serve merely to support the vehicle, and to keep the apparatus
horizontal by means of set screws b, b, b, by which the journals are
raised or lowered. The little board D, D, is fixed upon this frame.
An endless sheet of paper wrapt on the cylinder U, which turns
freely in its bearings, stretches on the whole length of this board D, D,
up to a pair of callender rollers a, a', the upper one of which is pressed
on the lower one by a spring 2, 7, that presses on its step; having
passed between these two rollers the sheet wraps half round the
top one, and is coiled on a third roller v, that rises as the diameter
increases. The main wheel C, has a diameter of 2 feet 8 inches
(0 mètre 7958), and will therefore make one revolution for each time
the apparatus advances by 8 feet 5 inches (2 mètres 50), which is
the circumference of the wheel C. This wheel gives motion to the
disc A, by means of two spur wheels of the same diameter and the
endless chain 7, 1. The disc A, drives B, by a similar gear, so that the
two discs make together the same number of revolutions as the driving
wheel. The diameter of the callenders is that of the driving wheel
C, & therefore they have 10 inches circumference. By introducing
between these rollers and the shaft h, h', of the pulley II, of the disc A,
a change of 1:50, we get for the relative lengths of the circumferences
developed from the driving wheel, and one of the rollers a ratio of 1:500,
which is a scale much used. Hence, whenever the large wheel rolling
on a horizontal ground has made 50 revolutions, a horizontal length
of 50 x 8 feet 5 inches 420 feet 10 inches (50 x 2 mètres, 50-125
mètres) has been measured, whilst the roller having made one revo-
lution has given out 10 inches of paper, or 3 of the space gone
through by the apparatus. The pencils or styles act as follows: a
square bar t, u, is fixed near the callenders on the edges of the board
by means of stands at the extremities of the bar. This bar carries
a certain number of sliding pencils which can be fixed beforehand
in the required position, so as to obtain a certain number of horizon-
tal lines, one of which, coinciding with the starting point of the move-
able pencil, traces out a general abscissa, and the others as many lines
of measurement at required heights. The moveable pencil L, which
describes the resultant of the abscissae and ordinates, i. e., the profile of

page_text: the ground, slide on two guide rods f, f. Its middle boss is tapped for
a three threaded screw d, of, inches (10 millimètres) pitch, so that
the pencil traverses 10 inches for every 25 revolutions of the screw.
The latter is driven by the shaft of the pulley H', of the disc B, by
means of the worm m', and the wheel train n', which changes the
motion like 1:2, so that if the pendulum P, is placed in one of the
extremne horizontal positions, to the right or to the left, and the pulley
on the maximum circumference of the disc, which is equal to its own,
the
made by the pencil is still 9 inches (0 mètre 25 centimètres)
for cach 50 revolutions of the driving wheel.
way
From this description and the relations of motion developed in the
preceding pages it is easy to see that, whatever may be the inclination
of the ground on which the apparatus moves along, the motion of the
paper will always be of the cosinus of the angle of inclination of
the ground with the horizon, i. e., of the general abscissa traced by the
fixed pencil T, and that as the moveable pencil moves proportionally to
the sine of the sanie angle it will rise or descend according to the direc-
tion in which the ground slopes by of the ordinate of the profile, and
will therefore give an exact diagram of it.
To avoid the friction of a screw with three threads, I substitute for it,
if required, an endless chain. The changes of scale are obtained by means
of a set of worms and proper change wheels, which replace, when re-
quired, the worms m, m', and the wheels n, n'. The machine, although
drawn on a scale of may have any other proportions, according to
the work it has to do.
I do not limit myself to the arrangement I have chosen as an illustra-
tion of my Patent, my Invention consisting chiefly in the theory
described in the beginning, and on Plate I. This mechanical combina-
tion may be arranged in an infinite number of different ways, all
having the same result, viz., the practical survey of ground. The two
straight edges y, g, which cross the board D, D, perpendicular to the
edges of the paper, and under which the sheet passes, are for the pur-
pose of tracing, at the will of the operator, ordinates at given distances,
which are determined by the distance of the two straight edges which
are held against the board by means of set screws.

page_text: I wish it to be distinctly understood that I claim the mechanical com-
bination involved in Pl. I., Fig. 3, of which the apparatus described on
Pl. II., and Pl. II. bis, is only an application or example, and that I
claim generally, besides the apparatus mentioned, firstly, the pendulum P,
or any other similar appendage suspended from a fixed axis, and acting
by means of levers a,, on pulleys HI, II', bearing tangentially against
the discs A, B, so as to keep them always at distances from the centre
of the respective disc, which are proportional to the sine and cosine
respectively of the angle made by the pendulum with the plane passing
through the centres of the discs. Secondly, the taking up of the first
motion given to the discs, in the manner described above or otherwise,
by pulleys which transmit the motion, and modify it so as to represent
by lines or by an index the sines and cosines of the angles made by the
pendulum P, as described.
In witness whereof, I, the said Jules Alexis Adrien Dumoulin,
have hereunto set my hand and seal, this Twelfth day of
December, in the year of our Lord One thousand eight hundred
and fifty-three.
J. A. A. DUMOULIN.
(L.S.)