A Calculating Machine for Surveying, Navigation, and similar Purposes.
Year: 1895

page_text: Date of Application, 10th Oct.,. 1895
Complete Specification Left, 10th July, 1896-Accepted. 3rd Oct.. 1896
Date of Application, 10th Oct.,. 1895
Complete Specification Left, 10th July, 1896-Accepted. 3rd Oct. 1896
PROVISIONAL SPECIFICATION.
A Calculating Machine for Surveying, Navigation, and similar
Purposes.
I PERCY WILLIAM MONCKTON HOLT Assoc. M. Inst. C.E. Survey Office
New Plymouth New Zealand do hereby declare the nature of this invention to be
as follows:-
-
A means whereby the co-ordinates or latitude and departure of traverses on land
or sea may be obtained from the given bearings and distances, without calculation
or use of mathematical tables; and also, whereby in any right-angled triangle in
which the angles and one side are known the lengths of the other sides may be
found.
The machine consists primarily of a hemisphere fixed to an axle movable about
the centre of the hemisphere through a quadrant of a circle, and two wheels of the
same radius as the hemisphere set at right angles to one another and touching the
hemisphere.
The machine may he made of any convenient size but it is essential that the
flanges of the two wheels be of exactly the same radius as the hemisphere.
Both wheels and hemisphere are to have recording discs or tires connected with
them for the purpose of registering the number of their revolutions and the method
of using the machine will be as follows:-
The axle of the hemisphere is to be set to the given bearing on the quadrant and
clamped in that position, and the recording discs or tires belonging to the wheels
and hemisphere set to zero (0). The axle is then to be turned about its centre
until the disc or tire attached to it & the hemisphere records the given distance of
the traverse. The discs or tires attached to the two wheels (whose flanges are in
contact with the surface of the hemisphere) will then record respectively the
latitude and departure of the traverse.
Similarly for solving any right-angled triangle in which a side and the angles
are known, the axle is first to be clamped at one of the acute angles and the
recording discs & tires brought to zero. The number of revolutions of the hemi-
sphere will then represent the hypotenuse, and of the wheels respectively the base
and perpendicular of the triangle-so that if the axle be turned until the given one
of these is recorded on its proper disc the other two sides will be shown on the
remaining dises or tires.
Verniers, clamps and tangent screws are to be fixed where necessary to assist in
the convenient working of the machine.
The materials used in its construction are to be those commonly used in
mathematical instruments, or such other materials as are suitable.
5th September 1895.
PERCY WM. MONCKTON HOLT,
New Plymouth.

page_text: A Calculating Machine for Surveying, Navigation, and similar
Purposes.
I, PERCY WILLIAM MONCKTON HOLT Assoc. M. Inst. C.E. of the Survey
Office, New Plymouth, New Zealand, 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 :-
can be
The object of my invention is to construct a machine by means of which the
co-ordinates or latitude and departure of traverses on land or sea
obtained from the given hearings and distances without calculation or use of
mathematical tables; and also by means of which in any right angled triangle in
which the angles and one side are known the lengths of the other two sides can be
found.
Figure 1 of the accompanying drawings is a plan and Figure 2 a side elevation
of the machine. Figure 3 is a section on the line A of Figure 1 with the arm E
set at 45°. The machine consists primarily of a hemisphere Z fixed to an axle Y
movable about the centre of the hemisphere through a quadrant X W, and two
wheels and of the same radius as the hemisphere set at right angles to one
another and touching the hemisphere as is shown in the drawings.
The machine may be made of any convenient size but it is essential that the
flanges of the wheels J and J be of exactly the same radius as the hemisphere.
The materials employed in its manufacture may be any of those cominouly used
in making mathematical instruments, or such other materials as are suitable.
In carrying out the invention there is fixed to a base plate V either solid or
perforated a bracket U to support the hemisphere Z and the arm E which
moves it.
The arm E is widened at the outer end and marked as a vernier of minutes, and
it slides along the edge of a quadrant marked in half degrees, with a clamp and
tangent screw T to fix the arm E at any required bearing. On the arm are fixed
two bearings S S in which the axle Y revolves; also the vernier of the distanco
wheel and the recording wheel G.
The divided plate of the quadrant is supported by and fixed to a channel-shaped
piece R, and the centre from which the arc is described is the centre of the
hemisphere.
The axle is rigidly attached to the hemisphere; it has a collar clamp and
tangent screw Q, and a crank handle K. It has also a raised thread of a screw y
around it working into a cog wheel y' connected with the recording wheel G by
frictional gearing; and the thread and cogs are so proportioned that ten revolu-
tions of the hemisphere cause one revolution of the wheel G, which is marked
from 0 to 9 denoting the number of revolutions of the hemisphere.
The hemisphere Z has a tire Fattached, divided into 100 equal parts marked
from 0 to 90 and a vernier to read to one-tenth of the divisions on F.
The latitude and departure wheels J J each work in a frame N N, the bearings
of the wheels being designed to cause the least possible friction.
The frames N N are hinged at the same point P and can be moved sufficiently
on their hinges to free the threads OO on the axles of from the teeth on the
wheels HH hereinafter described.
They are set with their centres at exactly the same height as the centre of the
hemisphere, and so that when the wheels JJ are touching the hemisphere they
are at right angles to one another, and that when the arm E is set at zero or 90°
the flange of one of the wheels is in the same straight line as the axle of the
hemisphere.

page_text: The frames N N are connected by a spiral spring M pulling the wheels against
the hemisphere with sufficient strength to prevent slip between the hemisphere
and the wheels when the former is being turned; and a trigger C is attached,
with connecting bars to throw the wheels off the hemisphere, and free the
threads when required. The frames N N are supported at intervals by
standards or walls fixed to the base plate, and are kept from lifting by clips
passing over the frames.
The wheels JJ have tires attached of slightly less diameter than the rim or
flange, and divided into 100 parts similarly to that on the hemisphere, and have
verniers attached to the frames.
Supported by standards fixed to the base plate are two wheels H and H already
referred to with toothed rims worked by the threads 00 on the axles of the
wheels J and J so proportioned that one hundred (100) revolutions of J and J
cause one revolution of H and H, whose circumferences are divided into 100 parts
and numbered.
The wheels and H H are held at zero when required by balanced bars a a
of T section notched for cams L L and with curved arms fitting casily into holes
on the rims of H and H.
The sliding weights D D either press the bars down on the cams or tip them up
so that the wheels can revolve freely.
All the wheels G, H H and J J are thin and hollow, and have balance weights
to make them turn to zero when released.
The method of working the machine is as follows:—
Press the trigger C towards the centre, slide the weights D D from the centre;
and move the wheel Gout of gear. (This adjustment is needed only when
commencing to work.) Clamp the arm E at the given bearing; set all the
recording wheels F, G, H H and JJ at zero, sliding the weights D D towards
the centre, putting the wheel G in gear, and clamping the wheel F. Release the
trigger C, and slide the weights D D from the centre; turn the hemisphere by
means of the handle K until the wheels F and G record the given distance, and
clamp with Q.
The wheels H J, and H J will then record the latitude and departure.
Similarly for solving any right angled triangle in which a side and the angles
are known, the axle is first to be clamped at one of the acute angles and the
recording discs and tires brought to zero. The number of revolutions of the hemi-
sphere will then represent the hypotenuse, and of the wheels respectively the base
and perpendicular of the triangle, so that if the axle be turned until the given one
of these is recorded on its proper disc the other two sides will be shown on the
remaining discs or tires.
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. In a machine for obtaining the co-ordinates of traverses and for other similar
purposes, the combination of a hemisphere adapted to revolve and also to be moved
about one of its central axes through a quadrant of a circle, and of two wheels set
at right angles to each other of the same radius as the hemisphere and capable of
being turned by contact with the hemisphere when it revolves, substantially as and
for the purpose bereinbefore described.
2. The traverse co-ordinate reducing machine constructed and working
substantially as herein before described with reference to the accompanying
drawings.
Dated this 7th day of July 1896.
H. E. SHERWIN HOLT,
Agent.