Tubular and Rotary Scales and Traversing Mensurator for Plotting and Ascertaining Dimensions on Plans and such like Drawn to Scale in Terms of Chains, Feet, and Links and Inches.
Year: 1886

page_text: Tubular and Rotary Scales and Traversing Mensurator for Plotting
and Ascertaining Dimensions on Plans and such like Drawn to
Scale in Terms of Chains, Feet, and Links and Inches.
I FRANCIS OBRÉ FERGUSON of Gothic Cottage Goldhawk Road Hammersmith
London W. Architect & Surveyor assisting in the Estate department of the London
and North Western railway Company at Euston Station London N.W. do hereby
declare the nature of this invention to be as follows:-
To one end of a hollow brass cylinder is fixed a circular wheel guaged to a certain
known size or circumference (which is to traverse the object to be measured) both of
which will be made to revolve on a hollow telescopic axle passed through their centres
and to make a certain number of revolutions and forced to return the same number of
revolutions by means of a spring. The cylinder will be less in diameter than the
traversing wheel and will carry a number of separate thin cylinders each fitting over
the other tightly but removeable and on each of which will be marked the scales in a
spiral form and the number of divisions or parts in terms of feet and inches or chains
feet and links as the case may be and according to the various and different scalos
used for measuring lengths and distances and plotting dimensions on plans drawings
and such like to said scales and as may be contained in the number of revolutions of
the known developed circumference of the gunged traversing wheel. On the intrados
of the hollow cylinder fixed to the guaged wheel will be formed a spiral worm or
screw which as it revolves forces a kind of leg which cannot revolve, in and out of
the cylinder sliding in a kind of slot formed in the fixed telescopic axle. To this leg
is fixed an indicator turned over and outside the cylinder and rotary scales and as the
cylinder revolves will force the indicator to follow the same movements as the leg.

page_text: Another wheel of the same diameter as the first mentioned will revolve free on the
other extremity of the axle. The said axle will be in two parts and screwed together
about midway when required. A marker and a plumb picce will be attached on the
outside face of the traversing wheel. If therefore the traversing wheel be made to
revolve over any object, the scales will rotate with it and the indicator not revolving
will point on the said scales any distance traversed and according to the scale used.
The instrument will be made in various sizes according to the developed circumference
and number of revolutions of the traversing wheel and the scales will be made and
developed accordingly.
Dated this 9th day of November 1886
Tubular and Rotary Scales and Traversing Mensurator for Plotting
and Ascertaining Dimensions on Plans and such like Drawn to
Scale in Terms of Chains, Feet, and Links and Inches.
I FRANCIS OBRÉ FERGUSON of Gothic Cottage Goldhawk Road Hammersmith in
the County of Middlesex Architect assisting in the Estate department of the London
and North Western railway Company at Euston London 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 is intended as a convenient and portable substitute for the usual
timber and ivory scales at present used and can be economically made true and
practically accurate and to contain two or three dozen of different scales easily
managed It may be made very small or as large as a watch and of different but
suitable materials such as brass I will now proceed to further describe with duo
reference to the figures on the attached drawings the manner in which I purposo
carrying out my invention and putting it into effect.
The exterior case of the instrument is made up of six sides forming a small box
five sides of which will be fixed to each other the sixth side B figure 5 being removeable
To this case at A figure 5 opposite side to B will be fixed an axle or arbor C
perpendicular to side A The side B being removable will be made to fit securely in
its place at pleasure This arbor supports and passes through the centre of a drum

page_text: made up in the following manner The two sides of the drum are of like circumference
The side nearest to B has fixed to it a circular tube D fitting tightly within a larger
and longer tube E which is fixed to the other side of the drum nearest to A This
drum is revolvable on the arbor (The sides of the drum will be slightly more in
circumference than the tube E To one side of the drum is fixed a large toothed
wheel F slightly less in circumference than the sides of the drum Within the drum
are two small cylinders G reduced in size at each end the ends fit into the sides of the
drum and are revolvable in same At one end of each of these cylinders will be fixed
a small toothed wheel H figure 5 These two wheels will gear with a toothed wheel
revolving on the arbor and kept in position by a pin These two small cylinders G
have a slit made in them best part of their length into which is secured the two ends
of a long strip of linen or other suitable material of sufficient width to lie neatly
between the sides of the drum This strip of linen on which are marked all the
different scales is fixed first to one of the small cylinders and then passed through a
thin slit in the tube part of the drum P figure 8 it is then coiled round the exterior
face of the said tube and again passed through the slit P and the remaining end of
linen is fixed to the other small cylinder inside the drum.
The toothed wheel F gears with a small toothed wheel or pinion K figure 4 which
is fixed to a circular bar L which has a small worm or thread formed on it and thus
forming a screw each end of this screw is reduced in size and is fitted into the
sides A and B and is revolvable in same On this screw is a female screw made to
move from side to side only to which is fixed a pointer M figure 8 with two legs fixed
to same which move one on each side of a small bar which is fixed to side A shown
at N figure 4.
One side of the case figure 3 has a glass of magnifying power if necessary through
which the marker or pointer may be seen The opposite side of case to last mentioned
and which is the bottom of the instrument has an opening made in it figure 6 to allow of
the sides of the drum to project slightly and revolve freely on the object to be
traversed and measured On the sides of the drum at A and B will be fixed small
pins which when they come in contact with the marker will completely stop the
motion of the drum this will be necessary to prevent any wedging up of the marker
on screw.
The sides of the drum will revolve by friction with the object traversed
G. E. H. F. D. P and the scales will revolve free of the exterior case.
A portion of the spiral scale would appear on figures 3 and 6 if shewn.
To form any scale on the linen coiled round the drum as before described it will
simply be necessary to traverse the instrument over any suitable object so as to bring
the pointer nearest to one of the sides say B then traverse the instrument again in
opposite direction and trace on the linen the spiral so formed by the pointer and as far
as the sides of the drum will permit then lay out on a flat cardboard the scale to be
represented then traverse the instrument untill the pointer is again at side B as far as
it is allowed by the pin to travel on screw then traverse the instrument along the
paper scale and mark on the spiral on linen the divisions passed over commencing at
zero which is represented by the face of the instrument and ending as far as there is
a spiral traced on the linen Having made all the necessary scales in like manner on
the long strip of linen they can then be printed and reproduced to suit similar sized
instruments.
To change a scale for another it will be necessary to take off the side B and revolve
by hand one of the cylinders on which is coiled the long strip of linen untill the
required scale appears on the outside of the drum. One of the cylinders coiling up
and the other uncoiling the said strip of linen The side B is then replaced in
position.
+
In using the instrument to measure with the required scale is made to appear as
described The instrument traversed and the pointer brought over zero the side of
the instrument taken to one place to be measured from and then by traversing to
the other place to be measured to the pointer will point on the spiral the distance
to scale.

page_text: Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declare that what I
claim is
1. Within a six sided case a drum revolvable upon an arbor or axle.
2. Within said case a pointer or marker made to move laterally in combination with
and outside the drum as described.
3. Within said drum two small cylinders revolvable in same.
4. The long strip of linen or suitable material upon which are traced many but
similar spirals and on which are inarked various scales in similar or different terms
such as chains and links Feet and inches and such like used by Surveyors to measure
drawings and plans, coiled round said drum which is made to traverse and revolve on
an object by friction with the sides of said drum.
.
5. The spiral scales formed on a drum in the above named terms and as set forth
and described.