IMPROVEMENTS IN MEANS AND APPARATUS FOR LAYING AND UNITING LENGTHS OF TUBES FOR SUBAQUEOUS COMMUNICATION
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Peter William Barlow and Peter
William Barlow, junior, at the Office of the Commissioners of Patents on the
17th February 1876.
PETER WILLIAM BARLOW and PETER WILLIAM BARLOW, junior, both of No. 26,
Great George Street, Westminster, in the County of Middlesex. "IMPROVEMENTS
IN MEANS AND APPARATUS FOR LAYING AND UNITING LENGTHS OF TUBES FOR
SUBAQUEOUS COMMUNICATION."
Our Invention relates to means and apparatus for laying and uniting under
water lengths of tubes intended to form a continuous tunnel or communication,
such tubes being made of metal, preferably in two thicknesses, with an annular
space between them filled in with concrete or other suitable material, for the
purpose of giving strength and rigidity and sufficient weight to sink the tube.
We erect piers on the bed of the channel or waterway which the tunnel is
intended to cross at intervals apart corresponding to the desired spans of the tube
lengths, and raised to the level at which the tube is intended to lic; on the
summit of each of those piers we fix a hollow metal box, having in each side a
semicircular hollow to constitute a saddle bearing for the tube, and we make this
hollow and the upper edge of the box with a lip all round it sufficiently broad to
receive a facing of caoutchouc or other suitable compressible packing material;
having previously constructed the tube in lengths sufficient to extend from pier to
pier, and close their ends, we float them over the positions which they are intended
to occupy, and then sink them by ballasting or by admitting water into cavities
provided for that purpose, so that each tube lies with one of its ends resting in the
semicircular hollow or saddle above described on one side of the box on one of the .
piers, and its other end resting in like manner on the next pier. There are thus on
each pier the ends of two adjacent tubes facing each other, but not united, both
these ends projecting into the interior of the box, which is made of sufficient
size to admit of workmen operating all round the inwardly projecting ends.
For the purpose of uniting these ends we provide a box similar to that upon the
pier, which box we lower in an inverted attitude, guiding it down by rods or chains
till it rests by its semicircular hollows on the two tube ends, and by its lip on the lip
of the box already on the pier. This upper box is provided with a vertical pipe or
funnel of sufficient height to reach above the surface of the water, and of sufficient
size to admit of workmen descending to the pier box. We pump the water out of

page_text: the cavity of the two boxes, so that the pressure of the exterior water, aided if
necessary by additional loading, forces them closely together, and compressing the
caoutchouc or other packing, prevents access of water to the cavity of the box; the
packing serving to make a sufficiently tight joint at the meeting lips of the boxes
and also around the peripheries of the tubes which are clamped between them.
When the water is pumped out workmen descend into the cavity and make good by
rivetting or otherwise the junction of the two lengths of tubes, after which the
upper box may be removed and employed for effecting the junction of another
pair of tube lengths, and the under box left on the pier may be filled with concrete
or masonry, which may extend over the junction of the tube lengths.