276
THE SEAS
‘
being increased slightly for the larger nets.
It stands to
reason therefore that an otter—trawl can be used with 3.
far larger opening than any beam-trawl, and for this reason
it has largely superseded the beam—trawl.
The height of
the mouth also is not limited by a frame, and in an efcient
otter—trawl it is probable that the upper edge of the mouth
or .“ head-line ”
may be_ten to fteen feet above the bottom,
‘
so that the chances of a sh escaping over the top of the
'
trawls are considerably decreased.
These traw1s are used
.
nowadays with an opening of anything up to 100 feet in width.
This bag—shaped net is drawn over the sea bottom by the
trawling vessel.
The weight of these nets out of water is
great and, when this large area of netting is exposed to the
frictionof the water as it is towed along, the pull is enormous.
For haulig these great nets powerful steam winches are:
required, carrying on their drums wire cable sufcient to
withstand a strain of many tons, for when by accident a '
net comes fast against a rock or submerged wrèck the
whole weight of the ship is taken by the wire.
'
‘
_
Some skill is requiredfor
“
shooting
”
these nets and an
inexperienced hand might soon be in
through
the net“ and warp winding round the propeller of the ship,
or going down belly upwards.
,
'
net is,hauled bytwo wire warps, one attached to
’
each
’
These Wires run over stout pulley wheels
xed in two heavy frames known as the “ gallows,” one
-
forward 'and one ait.
By the presence Or absence of the
'
“
gallows
”
one, can
tell at a glance whether a vessel is
tted for
'
On most trawlersthere are two pairs
of gallows so that the tra-wl maybe .“. shot ” from either
side of the ship.
Gener'ally two nets are
use, and. as
soon as one has been hauled up full of sh on the port side;_
'
thestarboard net is shot and so there is no waste of time
'
While the catch is being emptied., While the starboard-
THE SEAS
‘
being increased slightly for the larger nets.
It stands to
reason therefore that an otter—trawl can be used with 3.
far larger opening than any beam-trawl, and for this reason
it has largely superseded the beam—trawl.
The height of
the mouth also is not limited by a frame, and in an efcient
otter—trawl it is probable that the upper edge of the mouth
or .“ head-line ”
may be_ten to fteen feet above the bottom,
‘
so that the chances of a sh escaping over the top of the
'
trawls are considerably decreased.
These traw1s are used
.
nowadays with an opening of anything up to 100 feet in width.
This bag—shaped net is drawn over the sea bottom by the
trawling vessel.
The weight of these nets out of water is
great and, when this large area of netting is exposed to the
frictionof the water as it is towed along, the pull is enormous.
For haulig these great nets powerful steam winches are:
required, carrying on their drums wire cable sufcient to
withstand a strain of many tons, for when by accident a '
net comes fast against a rock or submerged wrèck the
whole weight of the ship is taken by the wire.
'
‘
_
Some skill is requiredfor
“
shooting
”
these nets and an
inexperienced hand might soon be in
through
the net“ and warp winding round the propeller of the ship,
or going down belly upwards.
,
'
net is,hauled bytwo wire warps, one attached to
’
each
’
These Wires run over stout pulley wheels
xed in two heavy frames known as the “ gallows,” one
-
forward 'and one ait.
By the presence Or absence of the
'
“
gallows
”
one, can
tell at a glance whether a vessel is
tted for
'
On most trawlersthere are two pairs
of gallows so that the tra-wl maybe .“. shot ” from either
side of the ship.
Gener'ally two nets are
use, and. as
soon as one has been hauled up full of sh on the port side;_
'
thestarboard net is shot and so there is no waste of time
'
While the catch is being emptied., While the starboard-