IMPROVEMENTS IN SHIPS' HATCHES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Richard Thomas Pawley at
the Office of the Commissioners of Patents on the 17th November 1882.
RICHARD THOMAS PAWLEY of Cardiff, in the county of Glamorgan, Master
Mariner "IMPROVEMENTS IN SHIPS' HATCHES"
This invention relates to improvements in hatches for steam or sailing ships.
In carrying out my improvements the top set of hatches is secured to the
coamings with beam and rebate in the usual way; underneath the top or outside
hatches I fit a second set of hatches secured at the top by means of a beam and at
the bottom in a rebate in a similar manner to the top hatches. The second hatch-
way is shorter and narrower than the outer hatchway so that a space is left from
the bottom of the second hatches to the coamings to form a water course to carry
off the water from the second hatches; the said water passes off through the
coamings by means of two or four outlets falling upon the deck-From the second
hatches and underneath the water course to the deck a double coaming is fixed
forming an air space open at the bottom running all round the hatchway, the said
air space is connected at one end (or at both ends if necessary) to an air chamber
having two partitions inside, about twelve inches from each end, secured to the
deck at bottom and up the sides and forming an air space over the top; the said
air chamber has an opening at the top with an outer socket, to which socket is
fixed a ventilator; at the bottom of the air chamber and level with the deck are
fitted two outlets.
By these improvements in hatches it will be evident that should the top or outer
hatches be carried away a second set is provided so that the cargo would be still
secured against the water getting in through the top hatches; the space between
the two sets of hatches forms a useful locker for spare ropes and further the air
space around the hatchway formed by and being between the double coamings
and open at the bottom admits the vitiated air from the hold the said air passes
over the two partitions into the air chamber and out through the ventilator and
should the said ventilator be carried away and the water get into the air chamber
the said water flows out through the two outlets at the bottom of the air chamber
so that the air has a free circulation in or out of the hold and no water can get in
to injure the cargo.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Richard Thomas Pawley in the Great Seal Patent Office on the
16th May 1883.
RICHARD THOMAS PAWLEY of Cardiff in the county of Glamorgan, Master
Mariner "IMPROVEMENTS IN SHIPS' HATCHES'
"
This invention relates to improvements in hatches for steam or sailing ships and
has for its object to increase the safety of the cargo and to provide free and
continuous ventilation.
In carrying out my improvements the top set of hatches is secured to the
coamings with beam and rebate in the usual way; underneath the top or outside
hatches I fix a second set of hatches secured at the top by means of a longitudinal
beam and at the bottom in a rebate formed in the top edge of the inside coamings
in a similar manner to the outside set. The second hatchway is shorter and
narrower than the outer hatchway, so that a space is left from the bottom of the
second hatches to the main coamings to form a water course to carry off the
water from the second hatches, the said water passes off through the main coamings
by means of two or four outlets falling upon the deck from the second hatches;
and underneath the water course to the deck a double coaming is fixed forming an
air space running round the hatchway and open at the bottom; the said air space
is connected at one end (or at both ends if necessary) to an air chamber, the said
air chamber being of a length equal to the width of the hatchway and the same
height as the bottom of the water course and about eighteen inches wide, having
two partitions fixed inside about twelve inches from each end of the air chamber
secured to the deck at bottom and up the sides to the coamings and outside plate
of air chamber respectively about two thirds the height of the air chamber
forming an air space between the top of the partition and the covering plate, the
said air chamber has an opening in the centre of the top plate with a spigot
projecting outward for fixing a ventilator thereto, at the bottom of the air chamber
and level with the deck and between the two partitions are fitted two outlets for
draining water from the air chamber.
In order that my invention may be fully understood I will now proceed to
describe the same by reference to the accompanying drawing in which figure 1,
represents a longitudinal sectional elevation shewing my improvements in ships'
hatches; figure 2, is a plan and figure 3, a transverse section of the same; figure 4,
is a view similar to figure 3, except that the air space is fixed outside the main
coamings. Similar letters in all the figures represent similar parts.
In figures 1, 2 and 3, A, and B, are the double hatches; C, is the water course;
D, the outlets; E, the air space; F, the opening to the bold; G, the air chamber;
H, the partitions in the air chamber G; K, the outlets from the air chamber; I, the
opening with spigot; J, the ventilator; L, and M, the coamings; N, the deck; O, the
deck beams.
The mode of constructing the double coamings L, and M, the air space E, and the
water course C, is clearly shewn in figure 3.
In figure 4, the air space E, is shewn fixed outside the main coamings the
construction being otherwise the same as that shewn in figures 1, 2, and 3.
By these improvements in hatches it will be evident that should the top or outer
hatches A, be carried away a second set B, is provided so that the cargo would be
still secured against the water getting in through the top hatches; the space
between the two sets of hatches forms a useful locker for spare ropes and further
the air space E, around the hatchway formed by and being between the double

page_text: coamings L, and M, and open at the bottom admits the vitiated air from the hold
the said air passes over the two partitions H, H, into the air chamber G, and out
through the ventilator J, and should the said ventilator J, be carried away and the
water get into the air chamber G, the said water flows out through the outlets K,
at the bottom of the air chamber so that the air has a free circulation in or out of
the hold and no water can get in to injure the cargo.
Having thus described the nature of my said invention and the manner in which
the same is or may be used or carried into effect I wish it to be understood that
I do not confine myself to the precise details herein laid down as the same may be
varied without departing from the principle of my invention but what I consider
to be novel and original and therefore claim as the invention secured to me by the
hereinbefore in part recited Letters Patent is :-
Firstly. The construction and use of a second or additional set of hatches as and
for the purposes herein before set forth.
Secondly. The general arrangement, construction and combination of the
coamings, water course and air space open to the hold and connected with the air
chamber as and for the purposes herein before described and represented in the
several figures of the accompanying drawing.
Thirdly. Constructing the two sets of hatches with a space between them as
and for the purposes herein before described and represented in the accompanying
drawing.
In witness whereof I the said Richard Thomas Pawley have hereto set my
hand and seal this fifth day of May in the year of our Lord one thousand
eight hundred and eighty three
RT. PAWLEY (L.S.)