Improvements in Distance Reading Telescopes and Levelling Instruments.
Year: 1894

page_text: Date of Application, 13th Apr., 1894
Complete Specification Left, 7th Feb., 1895-Accepted, 13th Apr., 1895
PROVISIONAL SPECIFICATION.
Improvements in Distance Reading Telescopes and Levelling
Instruments.
I, HENRY ERNEST MILNER of 7 Victoria Street, Westminster, in the County
of London, Civil Engineer do hereby declare the nature of this invention to be as
follows:-
This invention relates to the combination of a telescope and a graduated circle or
semicircle, by which linear distances are obtained as well as horizontal and vertical
angles, also levels of stations at any depression below or elevation above that of the
observer.
The telescope has two vertical and two horizontal wires or spider-web lines, which,
are set at such a distance, apart that their reading on a levelling staff gives the
linear distance of the staff.
From the point of intersection of two of these wires standing at right angles,
all angular measurements are taken both horizontally and vertically.
The instrument having been used for horizontal angles, is turned over at right
angles to its former position when, vertical angles of any magnitude can be taken,
or distances learned, and levels of any depth or height got by use of the pairs of
wires, which, are fixed in the focus of the eyepiece of the telescope as beforesaid.
This invention is the combination of the telescope and fixed parallel wires with
the graduated circle or semicircle, which, being turned over at right angles.as
already described enables large angles, and deep or high levels, and linear distances
to be got easily and accurately.
Fig. 1. shews the instrument when in use for measuring distances, the semicircle,
or circle of metal A, is then in a horizontal position for taking horizontal angles.
Fig 2. shews the instrument when it is turned over at right angles to its former
position and the semicircle or circle A stands in a vertical position for taking
vertical angles-and levels-and heights of buildings, trees, etc.
Fig. 3. gives a sectional or end view of the instruments when set up as in Fig. 1
for taking distances, etc. the eyepiece of the telescope being next the observer, as
it is when in use.
Dated this 12th day of Anil 1004

page_text: Improvements in Distance Reading Telescopes and Levelling
Instruments.
I, HENRY ERNEST MILNER of 7 Victoria Street, Westminster, in the County
of London, Civil Engineer 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:-
This invention relates to the combination of a telescope and a graduated circle or
semicircle, by which linear distances are obtained as well as horizontal and vertical
angles, also levels of stations at any depression below or elevation above that of the
observer.
The telescope has one vertical and three horizontal wires or spider lines, two of
the horizontal wires being set at such a distance apart that the difference of their
readings on a levelling staff gives the linear distance of the staff.
From the point of intersection of the middle horizontal wire with the vertical
wire which stands at right angles to it, all angular measurements are taken both
horizontally and vertically.
The instrument having been used for horizontal angles or distance measurements
is turned over at right angles to its former position, when vertical angles of any
magnitude can be taken, and levels of any depth or height be obtained by use of
the wires or spider lines which are fixed in the focus of the telescope as
beforesaid.
The base of the instrument has a system of parallel plates and four levelling
screws for levelling up the instrument.
The telescope has in addition an adjusting screw motion by which means levels
can be obtained without the trouble of wholly levelling up the instrument by using
the four parallel plate screws beforesaid.
This invention is the combination of a telescope and fixed stadium wires, with a
graduated circle or semicircle which being turned over at right angles as already
described, enables large angles and deep or high levels and linear distances to be
obtained easily and accurately.
In order that the invention may be fully understood, a drawing is annexed giving
different positions of the instrument and shewing the various essential parts of
same.
DESCRIPTION OF DRAWING.
Figs. 1 and 2 shew the instrument when in use for measuring distances and taking
horizontal angles.
Fig. 3 shews the instrument when turned over at right angles to its former
position on the pivots F. F.
The semicircle A is then in a truly vertical position for taking vertical angles,
and deep levels, or heights of buildings, trees, etc.
Fig. 4 shews an end view of the instrument with the eye piece of the telescope
removed and displaying system of diaphragm wires. The semicircle A is graduated
into degrees or parts of a degree and is read by a double index, so that the range of
a full circle is obtained, one index taking up the reading when the other has
completed the half circle of 180 degrees. This semicircle is used both for
horizontal and vertical angles.
The milled-head screw B immediately under the telescope near the eye-end
enables the telescope itself to be set rapidly and truly level so that levels can be
easily obtained without the trouble of wholly levelling up the instrument by means
of the four parallel plate screws.

page_text: in any
run,
The spirit level C fixed to the telescope when in the centre of its
position of the instrument, shews the telescope to be in a truly level position and
levels of stations can then be read off on a levelling staff.
The spirit level D fixed to the semicircle, is used for levelling up the instrument.
When the instrument is turned over at right angles, this spirit level being in the
centre of its run, is a constant of position, vertical angles being read off on the
graduated arc of the instrument by the index.
E. E. is a system of parallel plates and four levelling screws by which means the
instrument is wholly levelled up when required. To these plates are attached the
mahogany tripod legs by which the instrument is set up on the ground.
F. F are pivots attached to the underface of the semicircle A, on which the
telescope and semicircle are turned over at right angles and then used for taking
vertical angles and deep levels.
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-
The combination of the stadium wires in the telescope with the milled head
screw fine adjustment and the pivotted graduated circle or semicircle which being
turned over at right angles enables deep levels and large vertical angles and linear
distances to be obtained easily and accurately.
Dated this 7th day of February 1895.