IMPROVED ARRANGEMENTS OR COMBINATION OF VARIOUS MATHEMATICAL OR PHILOSOPHICAL INSERIMENTO PAD IM BAGHDING AND Amman
Year: 1875

page_text: LETTERS PATENT to Ridley Henderson, of Timsbury, near Bath, in
165
the County of Somerset, Mining Engineer, for the Invention of
"IMPROVED ARRANGEMENTS OR COMBINATION OF VARIOUS MATHEMATICAL OR
PHILOSOPHICAL INSERIMENTO PAD IM BAGHDING AND Amman D
Sealed the 13th, June 1876, and dated the 16th December 1875.
PROVISIONAL SPECIFICATION left by the said Ridley Henderson at
the Office of the Commissioners of Patents, with his Petition, on
the 16th December 1875.
.
I, RIDLEY HENDERSON, of Timsbury, near Bath, in the County of
Somerset, Mining Engineer, do hereby declare the nature of the said
Invention for " IMPROVED ARRANGEMENTS OR COMBINATION OF VARIOUS MATHE-
MATICAL OR PHILOSOPHICAL INSTRUMENTS FOR MEASURING AND OTHER PURPOSES,
to be as follows:―
"
C. My Invention is an instrument which I purpose naming the
mensor:" It is composed of numerous mathematical instruments
combined in one of a convenient, compact, and portable form,

page_text: .
measuring, say only 3 inches by 3 inches by 2 inches, and only
weighing about 2 pounds. It contains, and may be used as, a dial,
prismatic compass, circumferentor, hypothenite, limb for taking vertical
angles, quadrant, sun dial, level, protractor, scale of inches, scale
of chains, thermometer, barometer, anemometer, clinometer, double
callipers, plummet, magnifying lens, Nicol's prism, and a goniometer.
The dial box is, say, 2½ inches square by thick, and contains a
compass card 2 inches in diameter floating on an agate centre with
adjusting stops, and divided into degrees in the usual way, and for
reading the needle a prism is provided which folds down at the side
within the box when not required. It is also provided with a movable
ring round the inside periphery of the compass box which is divided
into 24 hours and subdivided into minutes, to be used as a sun-dial
in accordance with directions given. It also contains a thermometer
and double callipers, and is fitted with a screw to attach it when
necessary to the barometer box herein-after mentioned; outside the
· edges are marked with scales of chains and inches.
Between the dial box and the anemometer box, and made to fit both
so as to act as a cover to either, is a thin intermediate metal plate, about
say, 2 inches square, on which is hinged a strip of metal, say about
2 inches long by inch wide, to be used as a style or gnomon to cast
its shadow upon a straight line up the centre of the plate in a direct
line with the sun, thus enabling the time to be read by the needle of the
dial and the hour ring instead of by the shadow according to the usual
method. In this way any dial or compass may be converted into a sun-
dial and used as such in any latitude. Up the middle of the style or
gnomon I have made a fine slit with a small hole at each end by means
of which the magnetic variation of the compass may be ascertained
according to directions given and the accuracy of instruments of this
nature proved. I also make use of this strip of metal with its slit as a ;
circumferentor sight corresponding to the sight above the prism on the
opposite side of the dial box, the distance between the two sights being
53 inches, or thereabouts. I also use it to take vertical angles, there
being hinged on the plate to which it is attached a small quadrant, by
raising which the angle obtained by the sight can be read off to single a
degrees. I further use both the limb and quadrant as a goniometer to
measure the angles of crystallization, fracture, or cleavage of minerals.
On the remaining surface of this side of the intermediate plate I have

page_text: arranged some useful formulæ for surveyors, and on the other side of it
formulæ for mining engineers and others. The anemometer box before
mentioned is the central one, and measures, say, 24 inches square by
" thick. It contains an anemometer consisting of eight fans with bevel
gear and indicator. Fitted into the corners of this box, and visible
when using the dial, is a small circular level, also a magnifying lens and
a Nicol prism for examining through shallow water, also a socket in
which to fit the head of a tripod or other stand when required to be so
used. On the other side of this box is fitted in one corner a plummet,
and around the periphery of the fan case is a narrow circular plate
divided into degrees with a clinometer nicely.suspended or adjusted in
the centre, and radiating therefrom to mark the angle obtained by the
edge of the whole instrument being placed either under or above that of
which the angle of inclination is required. to be ascertained. The
divided circle is movable, and when used with a suspended clinometer
should be adjusted with its zero nearest the outside or upper edge of the
instrument and its 90 degrees nearest the end. I prefer to use a small
spirit level fitted as a clinometer, in which case the angle may be
ascertained with greater nicety than by a drop or suspended clinometer,
and I further use it in conjunction with two sights (one at each end of
the whole instrument, which can be drawn out when required) for
taking vertical angles. In using it thus the position of the divided
circle must be reversed, zero being nearest the end and the 90 degrees
nearest the outside or upper edge of the instrument. The third box is
the same size as the first (the compass box), and contains an aneroid
barometer arranged to measure not less than 1,800 feet below the surface
and 6,000 above. It is divided round the outside edges to serve as a
protractor.
.
The whole of the instruments thus arranged together are made in a
substantial manner with a view to their constant use, for which they are

page_text: 1
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Ridley Henderson in the Great Seal Patent Office
on the 16th June 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, RIDLEY
HENDERSON, of Timsbury, near Bath, in the County of Somerset,
Mining Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of December, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, givé and grant unto me, the said Ridley Henderson, Her special
licence that I, the said Ridley Henderson, my executors, administrators,
and assigns, or such others as I, the said Ridley Henderson, 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 "IMPROVED ARRANGE-
MENTS OR COMBINATION OF VARIOUS MATHEMATICAL OR PHILOSOPHICAL INSTRUMENTS
FOR MEASURING AND OTHER PURPOSES," upon the condition (amongst others)
that I, the said Ridley Henderson, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands
and seals, 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 Ridley Henderson, 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 :-
My Invention is an instrument which I purpose naming the " mensor."
It is composed of numerous mathematical and philosophical instruments
combined in a convenient, compact, and portable form, measuring, say,
about three and a half inches by three inches by two and three-quarter

page_text: inches, and weighing about two pounds. It contains, and may be used
as, a dial, prismatic compass, circumferentor, hypothonite, limb for
taking vertical angles, quadrant, sundial, level, protractor, scale of inches,
scale of chains, thermometer, barometer, anemometer, clinometer, double
callipers, plummet, magnifying lens, Nicol's prism, and goniometer.
The arrangement I prefer to adopt comprises three rectangular boxes
or cases hinged or suitably secured one to the other so as to form;
when shut up, one connected box or case.
The three component
boxes are hereafter referred to as No. 1, No. 2, and No. 3. No. 1 is
the dial box which is, say, two and seven-eighths inches square by nine-
sixteenths thick, and contains a compass card two inches in diameter
floating on an agate centre, with adjusting stops, and divided into.
degrees in the usual way, and for reading the needle a prism is provided,
which folds down at the side within the box when not required. It
is also provided with a movable ring round the inside periphery of
the compass box which is divided into twenty-four hours and sub-
divided into minutes, to be used as a sun-dial, in accordance with
given directions. It also contains at the side a thermometer and double
callipers, and is fitted with a screw to attach it when necessary to the
barometer box hereafter mentioned. The edges (outside) are marked
with scales of chains and inches.
Between the dial box (No. 1) and the anemometer box (No. 2), and
made to fit both -so as to act as a cover to either, is a thin intermediate
metal plate about, say two and three-quarter inches square, on which is
hinged a strip of metal, say about two and a half inches long by one-
eighth wide, to be used as a style or gnomon to cast its shadow upon a
straight line up the centre of the plate in a direct line with the sun,
thus enabling the time to be read by the needle of the dial and the hour
ring instead of by the shadow according to the usual method. In this
way any dial or compass may be converted into a sun-dial and used as
such in any latitude. Up the middle of the style or gnomon I have
made a fine slit, with a small hole at each end, by means of which
the magnetic variation of the compass may be ascertained according
to given directions, and the accuracy of instruments of this nature
proved. I also make use of this strip of metal with its slit as a circum-
ferentor sight corresponding to the sight above the prism on the opposite
side of the dial box, the distance between the two sights being five and
three-quarter inches, or thereabouts. I also use it to take vertical angles,

page_text: there being hinged on the plate to which it is attached a small quadrant,
by raising which the angle obtained by the sight can be read off to
single degrees. I further use both the limb and quadrant as a gonio-
meter to measure the angles of crystalization, fracture, or cleavage of
minerals. On the remaining surface of this side of the intermediate plate
I have arranged some useful formulæ for surveyors, and on the other side
of it formulæ for mining engineers, and others. The aneomometer box
(No. 2) before mentioned is the central one, and measures say two and
seven-eighths inches square and one inch thick. In contains an aneom-
ometer, consisting of eight fans, with bevel gear and indicator. Fitted
into the corners of this box, and visible when using the dial, is a small
_circular level, also a magnifying lens, and a Nicol prism for examining
through shallow water, also a socket in which to fit the head of a tripod
or other stand when required to be so used. On the other side of this box
is fitted in one corner a plummet, and around the periphery of the fan
case is a narrow, circular plate, divided into degrees, with a clinometer
nicely suspended or adjusted in the centre, and radiating therefrom, to
mark the angle obtained by the edge of the whole instrument being
placed either under or above that of which the angle of inclination is
required to be ascertained. The divided circle is movable, and when
used with a suspended clinometer should be adjusted with its zero
nearest the outside or upper edge of the instrument, and its 90 degrees
nearest the end. I prefer to use a small spirit level fitted as a clino-
meter; in such case the angle may be ascertained with greater nicety
than by a drop or suspended clinometer; and I further use it in
conjunction with two sights (one at each end of the whole instrument)
which can be drawn out when required) for taking vertical angles. In
using it thus the position of the divided circle must be reversed, zero
being nearest the end, and the 90 degrees nearest the outside or upper
edge of the instrument. The third box (No. 3) is the same size as the
first (the compass box), and contains an aneroid barometer arranged to
measure not less than 1,800 feet below the surface and 6,000 above. It
is divided round the outside edges to serve as a protractor.
The whole of the instruments thus arranged together are made in a
substantial manner, with a view to their constant use, for which they
are in all respects well adapted.
Having now particularly described and ascertained the nature and
object of my said Invention, and in what manner the same is to be

page_text: performed or put in practice, I hereby declare that I claim the
Invention of the improved arrangements combining together various
mathematical or philosophical instruments for measuring and other
purposes, substantially as herein-before set forth and described, it being
understood that I do not claim any of the instruments arranged
and combined as described separately considered, except as regards
the time or hour ring in the compass box and the method of ascertaining
the variations of the magnetic needle, all substantially as herein-before
set forth and described.
.
In witness whereof, I, the said Ridley Henderson, have hereunto
RIDLEY HENDERSON. (L.S.)