Year: 1885

page_text: I WILLIAM HENRY LINDSAY of .14 South Wharf Paddington Basin in the
County of Middlesex Engineer do hereby declare the nature of this invention to
be as follows:-
According to this invention I form a fire proof floor of a number of rolled girders
(preferably the ordinary double headed girder) ranged at equal distances apart and
parallel with one another. Through the vertical ribs of the girders holes are bored
close to the top and bottom flanges at distances say of from 12 to 18 inches apart.
Steel wires are threaded through these holes passing across from one side of the
floor to the other-one set of wires passes through the holes below the upper head
of the girders and another set of wires through the holes above the lower heads
of the girders-rigid distance pieces are also inserted between the parallel rails to
keep them at the required distance apart. The wires in the upper and lower sets
are vertically one below the other. In the spaces between the girders the wires
which are above and below one another are bent or both bent and twisted together
and other steel wires running parallel with the girders threaded between them to
retain them in their bent position-these wires which are parallel with the girders
may also if desired be wound once or twice around each pair of cross wires where
they are twisted together so as still further to bind all the wires the one to the
other.
The whole of the structure formed in this way is then embedded. in concrete,
the concrete being made to extend a distance above and below the parallel girders.
In this way a floor is constructed of great strength and has the further advantage
that if there should be any cracking of the concrete of the floor no large portions of
the concrete could possibly drop away as it would always remain upheld by the
girders and wires.

page_text: I, WILLIAM HENRY LINDSAY of 14 South Wharf Paddington Basin in the
County of Middlesex 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 :—
According to this Invention I form a fire proof floor of a number of rolled girders
(preferably the ordinary double headed girder) ranged at equal distances apart and
parallel with one another. Through the vertical ribs of the girders holes are bored
close to the top and buttom flanges at distances say of from 12 to 18 inches apart.
Steel wires are threaded through these holes passing across from one side of the
floor to the other-one set of wires passes through the holes below the upper head of
the girders and another set of wires through the holes above the lower heads of the
girders-rigid distance pieces are also inserted between the parallel rails to keep
them at the required distance apart. The wires in the upper and lower sets are
vertically one below the other. In the spaces between the girders the wires which
are above and below one another are bent or both bent and twisted together and
other steel wires running parallel with the girders threaded between them to retain
them in their bent position-these wires which are parallel with the girders may
also if desired be wound once or twice around each pair of cross wires where
they are twisted together so as still further to bind all the wires the one to the
other.
The whole of the structure formed in this way is then embedded in concrete, the
concrete being made to extend a distance above and below the parallel girders. In
this way a floor is constructed of great strength and has the further advantage that
if there should be any cracking of the concrete of the floor no large portions of the
concrete could possibly drop away as it would always remain upheld by the girders
and wires.
Figure 1 of the drawings hereunto annexed shews a cross section of a portion of
a fire proof floor formed in the above way.
A A A are three of the parallel rolled girders, B B are wires threaded through
holes in the top and bottom of the vertical ribs of the girders.-C C are wires
threaded over the upper and below the lower wires B in the centre of the
spaces between the girders A. D is the concrete in which the whole structure is
embedded.
"
In place of one set of the wires B being threaded through the lower holes in the
girders and the other set through the upper holes they might each as shewn at
Figure 2 be threaded alternately through upper and lower holes. In this case two
longitudinal wires C are used in each space between the girders and they may be
twisted together on each side of the wires B. The arrangement shewn at Figure 1
is however the one that I prefer to adopt.

page_text: 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 fire proof floor composed of concrete having embedded in it parallel rolled
girders with cross wires threaded through them at top and bottom and with
the wires brought and held together at the centre of the spaces between the
girders.
2. The construction of fire proof floors substantially as herein before described
and illustrated in the drawing annexed.