IMPROVEMENTS IN THE CONSTRUCTION OF SHIPS AND OTHER NAVIGABLE VESSELS
Year: 1864

page_text: PROVISIONAL SPECIFICATION left by John Robinson at the Office of
the Commissioners of Patents, with his Petition, on the 9th November
1864.
I, JOHN ROBINSON, of Liverpool, in the County of Lancaster, Shipbuilder,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE CONSTRUCTION OF SHIPS AND OTHER NAVIGABLE VESSELS," to be as follows,
that is to say-
This Invention has for its object certain improvements applicable to the
construction of ships and other navigable vessels with flat or nearly flat
bottoms, diagonally planked, and without vertical timbers, as will be herein-
after described.
In constructing a vessel according to this Invention the keel is laid on the
blocks in the usual way, but is formed without rabbets or indrest. The stent
and stern posts are then set up, each of which are constructed with a good
large apron, and indrest thereon. Having determined the shape of the bottom,
temporary floors are placed across the keel at about every eight feet, and
which temporary floors are cut to the requisite length, and made fast to the
keel, and the outer ends are so level as to enable logs to be turned round
against the ends of the floors on both sides from the stem to stern post.
For a vessel of about, say, 150 tons burthen, these logs may be about fifteen
inches square, or larger if desired. The ends of the logs are fitted into the
stem and stern post, and bolted through and through. If the logs cannot be

page_text: got in one length, they may be scarphed in. such a position of their length as to
preserve their strength. Care must be taken to keep the lower parts of the
logs, say, about three inches below the line of the top of the keel, to allow for
the thickness of the outside fore-and-aft planking. The planking of the flat
of the bottom of the vessel is of three thicknesses, the two first of which
cross each at an angle of about 45 degrees to the keel, and extend right
across the flat of the bottom of the vessel. The third or outer thickness is
laid longitudinally fore and aft. All the three thicknesses of planking are
thoroughly fastened by vertical treenails, bolts, screws, or screw bolts and
nuts, or any other suitable fastening.
The outer ends of the first or upper tier of the diagonal planks take into
rabbets formed in the inner sides of the logs, about three inches deep, and the
ends of the second tier of diagonal planks overlap the first tier, and take into
a second rabbet of, say, six inches deep from the internal vertical line of the
logs. The third and outer thickness of planking is laid longitudinally fore
and aft. The edges and ends of the two outer planks are fitted into a third
rabbet formed in the inside of the bottom of the log, and overlap the second
tier of diagonal planking, say, about one inch and a half, and the ends of the
other longitudinal planks, which are laid fore and aft, also take into a con-
tinuation of the said lower grooves or rabbets. The three thicknesses of
planking forming the flat bottom of the vessel being now securely fastened
together by vertical treenails, or in any other convenient manner, the
temporary floors are removed.
If preferred, the lower outer edge of the logs may be slightly rounded off,
and the ends of the lower tier of diagonal planks may be slightly chamfered
off to give a slight rise to the two outer planks of the flat bottom of the
vessel..
A pair of small sister logs or clamps are placed on each side of the vessel,
one being placed on the bottom, and bolted to the main log, and the other on
the top, and which is also bolted to the main log. The side of the vessel may
consist of two, three, or more thicknesses of planking, placed diagonally in
opposite directions, referenco being had to circumstances and the size of the
vessel to be constructed, but for a vessel of, say, 150 tons burthen, two
thicknesses of planking it is believed will be found sufficient, the lower ends
of which planking take into grooves formed in the outside of the logs, each
thickness of planking overlapping each other, say, about three inches, in the
same way as the planking of the flat bottom. The planking of the sides of
the vessel is carried up to the gunwale, or extended upwards so as to form
the bulwarks, in which case they are covered with a rail grooved on the

page_text: under side to receive the heads of the planks, which latter, modification is
preferred when not considered too heavy.
Iron or other metal straps are fitted over the logs and sister logs or clamps
on the top and sides of the logs, and are bolted to the bottom and sides of the.
vessel, and through the logs and upper and lower sister logs or clamps..
When the shearing down for the gunwale is done, two, three, or four
longitudinal streaks, extending fore and aft, are turned over the outside of the
heads of the diagonal planking, the lower edge of the lower and upper edgo
of the upper streak being let in, say, one inch, for the purpose of making a
good abutment and a stop for the oakum in caulking. Two or three streaks,
as clamps are fitted round the inside of the vessel to receive the ends of the
deck beams, and to form longitudinal ties; these are bolted through and
through the outside planking, also up and down through each other at, say;.
every three feet. When the diagonal planking of the vessel is carried up to
form the bulwarks, a plank of about, say, nine inches wide, and about two
inches and a half in thickness, is turned round underneath the rail inside and,
out, and which is let into the diagonal planking, say, about one inch and a
half at each side, when the whole is surmounted by the rail.
The waterways are fitted on the top of the deck beams, and up against the
diagonal, planking, and which waterways are cogged or dovetailed to the
beams, and well bolted through the diagonal planking, and the outside fore-
and-aft streak of plank; then fit a gunwale from the outside up against the
waterway on top of the heads of the diagonal planking; stantions of iron are
then secured on the top of the waterway, or wooden stantions may be bolted'
to the inside of the inside planking to receive tho rail and bulwarks.
In constructing vessels according to this Invention the keel is left loose so
that the entire flat of the bottom may be thoroughly treenailed or otherwise
fastened and caulked, including that part which is covered by the keel, after
which the keel is replaced and bolted through the bottom and keelson; or, if
preferred, the keel may be fitted against the second or lower thickness of
diagonal planking, in which case the fore and aft planks or garboard streaks
may be fitted into rabbets formed on the sides of the keel, or in the case of
small vessels, such as flats or lighters, where tho draught of water isa con-
sideration, there may be a thickness of four-inch plank used, instead of the
keel.
As it may be found somewhat difficult to obtain the desired shape forward
and aft, it is recommended to use two or three pointer breast hooks fitted in
their respective places foreward and aft, and bolted to the stem and stern post,
and using good stretchers across their ends to keep them to the desired

page_text: breadth, as these pointer breast hooks will not only facilitate the construction,
but can remain to be bolted off as hooks.
!
In vessels under thirteen feet depth of held, in addition to the main keelson,
two sister keelsons are used, one placed on each side of the main keelson about
half way between the keelson and bilge. These sister keelsons are about
two-thirds the size of the main keelson, and are well bolted through the
bottom of the vessel.
Vessels constructed with two or more tiers of beams have fitted under each
tier three clamps, each of, say, twelve inches deep, and of sufficient size
according to tonnage; bolted on the inside ceiling, so as to receive the whole
beams, and which clamps are bolted together edgeways about every three
feet. The main hatch beams it is preferred to construct double, and truss
them according to the Specification of Patent granted to the applicant, dated
4th December 1862, and No. 3256, and if found necessary the deck beams
may be strengthened by trussing as many beams as may be deemed necessary,
according to circumstances.
To prevent the wounding of the rabbeted logs by forming the rabbets
therein, a clamp may be bolted on top of the log, of sufficient size, and
Keeping it back, so as to form the first rabbet of the side planking, and the
same may be done in the inside of the logs to form the rabbet for the inner
or first layer of diagonal planking, formed in the bottom, by which arrange-
ment the outside logs are much strengthened.