IMPROVED APPARATUS FOR ASCERTAINING, THE STATE OF SEWERS, TUNNELS, DRIFTS, OR OTHER SUBTERRANEAN WORK, PART OF WHICH APPARATUS IS APPLICABLE TO LEVELLING PURPOSES
Year: 1865

page_text: PROVISIONAL SPECIFICATION left by Richard William Barnes at the
Office of the Commissioners of Patents, with his Petition, on the
25th March 1865.
I, RICHARD WILLIAM BARNES, of the City of Manchester, in the County
of Lancaster, Civil Engineer, do hereby declare the nature of the said
Invention for "IMPROVED APPARATUS FOR ASCERTAINING, THE STATE OF SEWERS,
TUNNELS, DRIFTS, OR OTHER SUBTERRANEAN WORK, PART OF WHICH APPARATUS
IS APPLICABLE TO LEVELLING PURPOSES," to be as follows:-
This Invention has for its main object the examination or the ascertaining
of the state of sewers, tunnels, drifts, or other subterraneous work without
the person who is conducting the inspection having to be in close proximity
to or in the immediate vicinity of such work; and consists, firstly, in the use
and application of a lantern which is constructed with an outer and inner-
casing so that the space between the said casings forms one or more chambers
or passages for the requisite amount of air to support the flame of the lamp,
and which quantity of air is supplied through the top part or roof of the
lantern, in order that when necessary the said lantern may be sunk in water
until the flame of the lamp is on a level with or below the surface of the
A cavity of à triangular, rectangular, polygonal, or other suitable
shape is formed between the outer and inner casings of the lantern, the ends
of which cavity are open for the purpose of enabling a staff or rod (herein-

page_text: after described) to be passed through, or an equivalent for the said cavity
may be constructed on the outside of the lantern for the same purpose, and
such lantern may or may not be provided with a reflector.
The second part of this Invention relates to what may be called the
reflecting apparatus, which consists of a suitable framework provided with a
similar shaped cavity to the one in the lantern, herein-before described,
which is also for the purpose of enabling a staff or rod (herein-after described)
to be passed therethrough, in which framework a reflector (made of metal or
any other suitable material) is mounted and so arranged as to be adjustable
to any required angle upon its own axis by means of a tangent screw or other
suitable means.
Thirdly, this Invention consists of a staff or rod made of metal, wood, or
any suitable material, and which, for the sake of portability, it is preferred to
hinge together in parts, so that it may be doubled up into a portable form; and
to ensure rigidity when opened out to its full length, internal bolts (the handles
of which are flush with the outer surface of the staff or rod) may be inserted
longitudinally at the end of every one of such parts, so that when such bolts
are pushed out or locked they will effectually and rigidly lock and fasten the
parts together in a straight line; it is also advisable to graduate or mark
divisions upon the said staff or rod.
It will be readily understood that such a staff or rod is equally applicable
as a levelling staff for levelling purposes, but to be used in conjunction with
the lantern and reflecting apparatus, herein-before described, it is necessary
to have the said staff or rod formed externally of the same shape and size as
the cavity in or its equivalent on the outside of the lantern or on the reflecting
apparatus, in order that when passed through such cavities the lantern or
reflecting apparatus respectively may be moved along or have their positions
altered upon the said staff or rod, and to facilitate such motion pulleys or
their equivalents may be mounted in the said staff or rod, over which a band,
cord, chain, or pliable metal wire (attached to the lantern or reflecting
apparatus) is passed, so that by means of the graduations or divisions marked
upon such staff or rod, the lantern and reflecting apparatus respectively may
be regulated to the greatest nicety. When so arranged the said staff or rod
is intended to be used as a guide for directing the rays of light from the
lantern in any required direction to the reflecting apparatus, which is also
mounted upon an exactly similar staff or rod. It will be readily apparent
that if such a lantern is placed in one part of a tunnel (for instance), the rays
of light proceeding from such lantern may be. reflected from the reflecting
apparatus situated at another point of the tunnel in any required direction,

page_text: provided that no obstacle intervenes, and by means of such apparatus the
state of sewers, tunnels, drifts, or other subterranean work may be examined
without the person conducting the inspection having to descend down into
such subterranean works, or without his having to be in close proximity to
such works.