An Improved Rapid Sketching Instrument.
Year: 1891

page_text: Date of Application, 23rd Jan., 1891
Complete Specification Lelt, 20th Oct., 1891-Accepted, 12th Dec., 1891
PROVISIONAL SPECIFICATION.
An Improved Rapid Sketching Instrument.
WILLIAM WILLOUGHBY COLE VERNER Captain, Rifle Brigade Junior
United Service Club Charles Street London, W. do hereby declare the nature of
this invention to be as follows:--
Improved sketching instrument consisting of a combination in one piece of
apparatus of an improved protractor having a clinometer, a magnetic compass with
moveable meridian, and folding sights for taking vertical & horizontal angles: the
plumb bob forming the indicator for the clinometer being protected by a semi-
circular metal plate. The protractor in which the clinometer, compass, & folding
sights are inserted & fixed, being preferably of wood & has the ordinary scales as
well as some special ones and formula for calculating heights &c.
Dated this Twentieth day of January 1891.
WILLIAM WILLOUGHBY COLE VERNER.
COMPLETE SPECIFICATION.
An Improved Rapid Sketching Instrument.
WILLIAM WILLOUGHBY COLE VERNER Captain, Rifle Brigade Jumor
United Service Club Charles Street, London, W. do hereby declare the nature of
this invention and in what manner the same is to be perforined, to be particularly
described and ascertained in and by the following statement:-
An improved sketching instrument consisting of a combination in one piece of
apparatus of an improved protractor having a clinometer, a magnetic compass with
moveable meridian and folding sights for taking vertical and horizontal angles.
The protractor is preferably made of box or other hard wood but can be made of
vulcanite, celluloid, papier maché, ivory or other suitable material, and is sufficiently
thick to have a countersunk space for the plumb bob A to swing in. This plumb
is pivoted at B and controlled by a spring stop at the back which on being pressed
releases it & on the pressure being withdrawn fixes it. Asemi circular () or other
suitable shape metal plate, or thin substance of a hard nature is fastened to the
protractor & supported on studs, small pillars or a bridge or bridges in such a way
as to protect the plumb bob from getting bent or flattened down and so affect its
proper working or free swinging. In order that the controlling spring may be
sufficiently strong to act with certainty the fitting for it is made as long as possible
consistent with the protractor being a reasonable thickness for the pocket and con-
venient use, & in order that the plumb bob fitting shall agree with the height
at B the stem of plumb bob is bent upwards, hence the necessity of a protecting
plate to preserve its shape.
The compass D has a specially designed card that shows the cardinal points and
degrees and in order that the figures showing the degrees may be large for the space
at disposal the zero or noughts are dropped in each case thus 18 would be 180
& 35, 350 degrees. The revolving ring containing the glass carries round a line
drawn across or fixed across the centre of glass E & this permits of it being set to
the line of direction," or to the scale of degrees F on the protractor around the
compass box for magnetic variation.
The sights G. G₁ are of the regular pattern generally used in sight rules for
plane table & other work and for convenience of packing are made to hinge up and
down. These are looked through when the protractor is held edge up for vertical

page_text: angles and when it is flat, for horizontal angles, the compass on settling to the
magnetic meridian showing the latter while the plumb bob shows the former.
In making rapid and other sketches it is used as follows:-After taking up a
position that properly commands the country, and a piece of high ground would be
best for this, the artist, surveyor, or soldier sketching would open his sketch book
or place his sketching block on a fence or other rest and then the protractor flat on
top of that, so that the compass comes to rest. He now rotates the line (& glass)
and brings it exactly over the N & S of the compass card. This if the sights of
the protractor are pointed in the general direction of the sketch will give the line
of direction & a line along either edge of the protractor drawn on the paper will
shew it. It will be necessary to draw a line showing N & S on the sketch and if
the revolving line on compass is placed parallel to the sights it will be the
magnetic meridian but if set to the variation by means of the outside degrees F
then true N & S. This once set it is only necessary to direct the sights to the
various objects to be included in the sketch and with a certain mark on the paper
or point (say a pin stuck in) to denote his starting point he draws a series of lines
to indicate the angular position along the edge of the protractor, writing along each
line the name of the object to which the line refers. He now uses the protractor
edge upwards and on pressing the stud at back allows the plumb bob to swing
freely and placing the slotted sight G to his eye he intersects the top of the object
or gets it in exact alignment with the object of which he desires to know the height.
This will give him the vertical angle in degrees by reference to the arc of degrees
on front of protractor & if he knows (which he can ascertain by pacing or measuring
with a small range finder) the distance he is away from the object he can find the
height or vertical interval as it is called, by using the formula on the back of the
protractor for the purpose. Various scales are given on the protractor so that
the map can be made to 6 (or 3) inches to the mile and 4 (or 8) inches to the mile
while various other formula & scales gives him rapidly other useful & necessary
information especially for military sketching or prospecting in little known
countries.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed. I declare that what I
claim is,
1. The combination in one piece of apparatus of an improved protractor, clinometer,
magnetic compass with moveable meridian, and folding sights for taking vertical
& horizontal angles substantially as described.
2. The protecting plate of metal or other hard substance and support or
supports to prevent the plumb bob of clinometer getting injured substantially as
described.
3. The are or circle of degrees placed on the protractor for correction of
magnetic variation of compass & so showing true N. & S. substantially as herein
described.
Dated this Fifteenth day of October 1891.
WILLIAM WILLOUGHBY COLE VERNER,
Captain, Rifle Brigade.