Improved Means and Appliances for Levelling.
Year: 1893

page_text: Date of Application, 8th May, 1893.
Complete Specification Left, 11th Sept., 1893-Accepted, 10th Feb., 1894
PROVISIONAL SPECIFICATION.
Improved Means and Appliances for Levelling.
Į EDWARD MANWARING SHELDON of 1, Broad Street Oxford, Architect, do
hereby declare the nature of this invention to be as follows:-
This invention relates to improved means and appliances for levelling, intended
to provide a simple and inexpensive method of finding levels without requiring the
use of a theodolite, or other similar instrument.
In carrying my invention into practice, I employ two levelling rods, marked
with feet and inches, or other unit of measurement, which are placed in or on
the ground in an upright position, at the required points. To obtain points on
these rods which shall be at the same level, I attach each end of a cord to the
rods by suitable means, as hereinafter described, the cord hanging more or less
taut between them. At a central point on this cord I suspend a spirit level,
having a hook at each end by which it is hooked on to the cord. If the ends
of the cord be at the same level, and the spirit level be accurately placed in
the centre the indicating bubble will take up its central position, and one end of
the cord must be raised or lowered until this is observed.
The spirit level should be of peculiar construction, having an opening in the
cover at the bottom, as well as at the top, so that it can be viewed from under-
neath. To regulate the height of the cord, a sleeve is placed on each rod, with a
thumb screw or other appliance, by which it can be fixed in any desired position,
and a hook over which a ring or loop on the end of the cord can be placed. The
marks in the rod indicate the height at which it is fixed. Either end of the cord
can thus be readily raised or lowered until the position indicating the level is
obtained. By this arrangement those engaged in the work can place the rods in
their required positions, note the positions of the cord, and moving the rear rod on
in front of the other, take the next reading, the sleeve on the latter rod remaining
in position indicating the level last obtained, no instruments excepting the rod and
spirit level being required to be moved.
In cases where the posts are at varying distances from each other, I provide a
device by which the centre of the line is immediately and accurately obtained.
The cord is doubled at its centre, and wound from that point on a reel, so that equal
lengths of cord in each direction are unwound. These pass through a small block,
having two side holes, through each of which one side of the line passes, the block
always being at the centre of the part of the latter which is unwound.
This block may be furnished with lugs or other means by which it can be
attached to the reel. This arrangement will allow the cord to be unwound more
easily. The line when sufficiently unwound is attached to the rods and the block
removed from the reel, the line is then tightened up and secured to the block,
giving the central point accurately, the level being hung by its two hooks at that
point, the hooks being attached on each side of the block.
LUK SE UBY UL
WATCO MUX OCH UY ULOY ACC
GEO. H. RAYNER,
37, Chancery Lane, London, Agent for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improved Means and Appliances for Levelling.
I, EDWARD MANWARING SHELDON of 12, Broad Street, Oxford, Architect,
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 improved means and appliances for levelling, intended
to provide a simple and inexpensive method of finding levels, without requiring the
use of a theodolite, or other similar instrument.
In taking levels of land, to carry my invention into practice, I employ two rods
or other supports, which are placed in or on the ground in an upright position at
the required points. To obtain points on these rods or supports which shall be at
the same level, I attach each end of a line to them, the line hanging more or less
taut between them. At a central point on this line I suspend a spirit level having
a hook or equivalent at each end, by which it is hooked on to the line. If the
ends of the line be at the same level, and the spirit level accurately placed in the
centre, the indicating bubble will take up its central position, and one end of
the cord must be raised or lowered until this is observed.
The spirit level should be of peculiar construction having an opening in the
cover at the bottom, so that it can be viewed from underneath. To regulate the
height of the line a sleeve is placed on each rod with a thumb screw or other
appliance, by which it can be fixed in any desired position, the sleeve having a
hook or projection to which the line can be secured. Either end of the line can
thus be readily raised or lowered until the position indicating the level is obtained.
By this arrangement those engaged in the work can place the rods in their required
position, note positions of the cord, and moving the rear rod on in front of the
other, take the next reading, when the sleeve on the latter may either remain in
position or be moved up or down to suit the contour of the ground.
In taking levels in connection with buildings or wherever it may not be necessary
or convenient to use rods, I strain the line from any required point or support to
another and suspend the level centrally on the line as before mentioned, raising one
end of the line until the level is ascertained.
The central point of any required length of line may conveniently be found by
doubling the whole line at the centre and winding from that point on a reel so that
equal lengths of line are unwound in each direction; these equal lengths of line are
then secured by a clip where required; the level is then hung with a hook on
either side of this clip which is the central point of the line. The centre may
also be found by means of a tape, one side of which is divided to any convenient
scale, and the other side, for one half of its length to half the first scale, the half
length thus having the same divisions as the full length on the other side, but to
half the scale. Thus if a certain length is measured off between any two points
the half length will be obtained by finding the corresponding division on the half
scale side of the tape.
In order that the invention may be more clearly understood, reference is had to
the accompanying sheet of drawings. Referring to Figs. 1 & 2 A. is the level and
is furnished with peculiarly formed ends e having a hook el a flat top e³ and a flat
base allowing it either to be hung on the line C or held under a surface, and
viewed from underneath, or placed on a surface in the usual manner. The level is
also furnished with two sight holes a & a one at the top and the other at the
bottom, allowing the indicating bubble to he seen from both the upper and lower
sides.
Figs. 3 & 4 give examples of the method of using the level in connection with
building, Fig. 3 showing the level A placed centrally on a line between two wall
plates, and Fig. 4 showing the levelling of brickwork in course of erection.

page_text: Fig. 5 shows the general system of levelling over rough ground. B representing
the rods & A the level hung centrally between them on the line C.
Fig. 6 is an elevation and Fig. 7 a sectional plan of a rod with a sliding
attachment for holding the line and Fig. 8 a section of a slightly modified
arrangement. B is the rod preferably furnished with a scale by which the height
of the adjustable sleeve D can be indicated. This sleeve is furnished with a
hook d and projections d' by which the cord can be held.
-
According to the arrangement shown in Figs. 6 & 7 the sleeve is fixed in
position by means of the set screws E the sleeve being adjusted by hand, or as in
Fig. 8 the rod may be furnished with a rack 6 and the sleeve with a pinion E¹
gearing into the rack, and allowing the sleeve to be raised and lowered in a
continuous and easy manner.
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-
1. In an improved system of levelling a spirit level having a hook or equivalent
at each end, to be hung on a line stretched from one levelling rod or point to
another, substantially as and for the purposes specified.
2. In an improved system of levelling, a spirit level having a hook or equivalent
at each end, by which it can be hung on a line stretched from one levelling rod or
point to another, and two sight holes, one at top and one at bottom, substantially
as described and for the purposes specified.
3. In an improved system of levelling, the combination with a level of the kind
claimed above, of two levelling rods each furnished with an adjustable sleeve, to
which a line is attached, constructed substantially as described and for the purposes
specified.
4. The improved means and appliances for levelling, comprising levelling rods,
spirit level and line, the whole constructed and operating substantially as described
and shown, and for the purposes specified.
Dated this 11th day of September 1893.
GEO. H. RAYNER,
37, Chancery Lane, London, Agent for the Applicant.