Boundary and Sighting Stone.
Year: 1898

page_text: Date of Application, 15th Jan., 1898-Accepted, 19th Feb., 1898
COMPLETE SPECIFICATION.
Boundary and Sighting Stone.
I, CARL BRANZKE, of 117, Linsenstrasse, München-Gladbach, in the Empire
of Germany, Architect, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
So-called boundary or sighting stones are employed in land surveying for the
purpose of fixing the boundary points and measuring points with exactness.
But in trigonometrical mensuration or surveying operations it was not possible
to adjust and fix the sighting rods in the hole provided for the purpose in the said
boundary or sighting stones, with accuracy and security in the vertical position,
because the sighting rod had to be rammed in by hand so to speak. The result
of this was that this hole in the sighting stone became wider with the lapse of
time, the rod had no secure bearing or guidance, and its adjustment and fixing
in an upright position was a tedious, inaccurate and lengthy operation.
Now the present invention has for its object to provide a device by means of
which the rod can be readily and accurately set up. This object is effected by
building in the boundary stone, a slit spring tube, the arrangement being such
that in order to set up the sighting rod, it is merely necessary to insert the said
rod into the said tube. Thus by allowing the rod to drop from a small height,
say 10 centimetres, into the tube, the said rod will be held fast by reason of the
spring action of the tube in a most accurate and secure manner. The elastic tube
has the further advantage that inferior and slender rods will always be held fast
in a secure and vertical manner.
The accompanying drawings illustrate a section taken through the boundary
stone fitted with the new device. a is the boundary stone. Into the hole b--which
is made slightly wider at the top-there is inserted the spring sleeve or tube c
which as shown in plan, is slit and is rendered elastic thereby. In order that the
elasticity of the tube shall have scope for action, the upper end of the tube c
is situated in a free space so that therefore the tube is able to move freely in all
directions.
If now a sighting rod be inserted with its point into the sleeve c, it forces the
latter apart and is securely gripped in a vertical position. It is preferable to
effect this by simply dropping the sighting rod from a suitable height into the
tube or sleeve, whereby the rod will at once adjust itself automatically in the
proper vertical position and be held securely in such position by the elastic
sleeve.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
-
(1) A boundary or sighting stone characterized by the arrangement of a slit
spring tube c for the purpose of enabling the sighting rod to be held fast in a
secure and vertical manner.
(2) A form of construction of the boundary or sighting stone specified in

page_text: Claim 1, characterized by the arrangement of a free space at the upper end of
the elastic tube c for the purpose of allowing the latter to have free play.
Dated this 15th day of January 1898.
ROBERT E. PHILLIPS, Assoc. M. Inst. C.E., M.I. Mech. E.,
Consulting Engineer & Patent Agent,
70, Chancery Lane, London, W.C., Associate Agent.