IMPROVEMENTS IN APPARATUS FOR LIFTING AND LOWERING BLOCKS OF STONE OR CONCRETE OR OTHER BUILDING BLOCKS, AND FOR DISENGAGING SUCH BLOCKS FROM THE LIFTING APPARATUS
Year: 1874

page_text: PROVISIONAL SPECIFICATION left by William Matthews at the Office
of the Commissioners of Patents, with his Petition, on the 20th
June 1874.
I, WILLIAM MATTHEWS, of 2, Westminster Chambers, Victoria Street,
in the City of Westminster, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS FOR LIFTING AND LOWERING BLOCKS
OF STONE OR CONCRETE OR OTHER BUILDING BLOCKS, AND FOR DISENGAGING SUCH
BLOCKS FROM THE LIFTING APPARATUS," to be as follows:-
This Invention has for its object improvements in apparatus for lifting
and lowering blocks of stone or concrete or other building blocks, and
for disengaging such blocks from the lifting apparatus.
For the purpose of obtaining a hold upon stone or concrete or such
like blocks, to enable them to be lifted and conveyed to any desired
spot, I employ an apparatus composed of two bars connected together
by links, which allow the two bars to lie against one another like the
plates of a parallel ruler, and also to move away from one another. The
apparatus is inserted into a deep hole formed in the concrete block.
The links by which the two bars are connected are not of equal length,

page_text: but are of gradually increasing lengths from the upper to the lower one.
By this means when the bar to which the lower ends of the links are all
jointed is hauled on the bars separate, and in doing so become inclined
to one another, the lower ends of the bars being further apart than the
upper ends, and thus the bars from one end to the other are pressed
against the sides of the hole, which are similarly inclined to one another;
and a secure hold is obtained upon the block. If on the other hand the
apparatus is raised by the other bar the bars come together and aro
readily drawn out from the hole.
For raising blocks of large dimensions .I prefer to use two Lewises
constructed as above described, and inserted into holes at a distance
apart from one another in the block, and with the bars to which the
upper ends of the links are jointed, coupled by short chains to the ends
of a beam, which at its centre is coupled by a link to the lifting chain.
The upper ends of the other bars of cach of the Lewises have a link
jointed to them, which can be turned over on to the ends of the beam. To
obtain a hold upon a block the apparatus is lowered and the two Lewises
guided into the two holes formed to receive them; the links jointed to
the ends of the bars above mentioned are then turned over on to the ends
of the beam, and when the beam is raised by the lifting chain these
links raise the bars to which they are attached, and cause the two bars
of each Lewis to separate from one another, and to bear against the sides
of the holes in the block as above explained. When the block has been
lowered into its place the apparatus may be quickly detached from it by
throwing off the links above mentioned from the ends of the beam, so that
when the beam is again raised the two bars of each Lewis will be drawn
together, and will readily leave the holes in which they were formerly
holding.
The turning over of the links may either be effected by hand or when
working under water or in inaccessible places; they may be thrown over
by pulling upon a cord which is led up to the stage or vessel from which
the block is being lowered, the cord at its lower end being connected to
weighted lever arms projecting from the links.

page_text: the two Lewises have been connected in a similar manner to that above
described to the two ends of a bar or beam, and are lifted by this bar
they hold securely in the block, but when disconnected from the ends of
the beam and raised by short coupling chains connecting each of them
to the beam at its centre, each Lewis is hauled upon in a line with the
hole in which it lies and is readily withdrawn therefrom. To facilitate
their withdrawal each Lewis may be divided longitudinally into two
wedge-shaped pieces, and the coupling chain be connected to that piece
which has its larger end uppermost. In this case the two parts of each
Lewis will be coupled together by a short chain, so that when one part
has been withdrawn the other is drawn out after it. In order to couple
such Lewises to the beam by which they are to be lifted, the upper end
of cach part of the Lewis has a loop formed upon it to link on to a
jointed dodge hook carried at the ends of the beam; the point of each
dodge hook is held by a link hooked over it, and this link is coupled to
a lever arm on an axis carried by the beam; on this axis is another arm
from which a cord passes to the vessel or stage from which the stone is
being lowered, so that by pulling this cord the dodge hooks may be set
free and the Lewises uncoupled, then when the bar or beam is again
raised the Lewises will be drawn upwards by the chains connected to
them in a line with the holes in which they lie, and will thus be
released from the holes as above explained. In place of attaching the
Lewises to the ends of the beam in the manner above described, the
beam may simply be provided at each end with a hook to hook into the
loops at the top of the Lewises, or other provision may be made for
readily attaching and detaching the Lewises to the ends of the beam.
In some cases the Lewises in place of being made in two parts might
be solid, and be similarly connected to a bar or beam attached to the
lifting chain.