The new North-west., 1897-02-26
LATEST in FISH NETS.
A FRENCH INVENTOR INTRODUCES
NEW METHODS OF SEEMING.


the Harvest of the sea-How Fish May
BE Captured In Large Quantities and
Before They Know 1t.
1t has frequently been a subject Of
comment that the methods in vogue for
gathering the "harvest of the sea-
have scarcely changed from century to
century. The bone Or ivory or wooden
fishhooks of the Eskimo or the south
sea islanders are represented, it is true,
in our higher civilization by the finely
pointed metal ones, but this is a refine
ment of manufacture, not an improve
ment in method. 1t is equally true that
their rude]y twisted bark nets are only
to be compared with the product of our
rope walks and twine factories, greatly
to the advantage of the latter. This in
dust1y, as old as humanity, has, SO to
7ay, made but a single step since its
birth. They are essentially the same
have always been employed for the fish,
ing industry that are i'll use today.
1t is frequently said, "The sea ought
to nourish the land" and in view of
the rich supplies of food which the sea
contains this seems to be just On the
other hand, the complaints of the fisher
men prove that their calling is far from
lucrative. We hear frequently of re-
gions where fish were formerly abundant
which at present are hardly producing
anything. What is the cause of this
state of things? There may in truth be
many causes, but it is largely due to the
crudeness of the methods employed.
Fish show a strong tendency for quit
ting the place where nets have been en-
ployed, which frighten them, or to
avoid returning if they are of migrate
ry habits.
On the other hand, the nets and
drags often tear up the bottom and dis
turb the spawning beds with the eggs,
and sometimes the young. These con-
siderations have led a gentleman named
Trouve to conceive a new system Of fish
ing, employing some of the methods of
modern science and overcoming, as he
thinks, some of the objections to the
antiquated methods.
He claims to have accomplished
among other results the attracting of
the fish into his tolls and capturing
them without frightening them and
without much wear and tear on the nets
themselves. In his nets, for instance, of
a cylindrical shape, the ring forming
the bottom has lead sinkers fixed to it
in the ordinary way, while the upper
edge consists of a rubber tube, which is
ia Communication by means Of a long
flexible rubber pipe with a reservoir i'll
the boat and which is supplied with
compressed air by means of one or
more pumps. Instead of being placed
in the boat this reservoir can in some
cases be arranged Oh shore or even OH
special buoy.
When thrown in the water in the
usual way, the rubber tube having been
emptied of air, the weight of the net
will, OF course, take it to the bottom,
where it forms a stationary mass of reIa-
lively small volume, which will not of
itself terrify the fish. Having proceeded
to attract the fish to the location by
methods which we will allude to further
on, as soon as there is reason to believe
that they have gathered in force stop
cock is opened, allowing the compressed
air from the reservoir to flow into and
initiate the tubular ring constituting the
upper border of the net. This ring as
a result, augments in volume and forms
a rigid mouth for the net, and at
given moment, in accordance with the
law of Archimedes, it becomes buoyant
and rises to the top of the water, carry
ing the net with it.
The important point is that this is
accomplished without noise and with.
out agitatiDg the water. The fish is not
alarmed, and is captured before he
knows it, without making any attempt
to escape
The same principle may be applied to
seine nets or purse nets.
1t is we'll known and recognized that
fish, in common with most terrestrial
animals, not excluding humans" are
strongly attracted by anything which
glitters. Mr.. 1'rouve has taken advan-
tage of this and has constructed lumi-
nous buoys containing batteries Or ac-
oumulators connecting with incandes-
cent lamps. A fiattened reflector spreads
the light over a wide extent. These
buoys are placed with other bait in the
nets, and the fish are attracted from all
sides, like moths to a candle, and be-
come prey.
The next thing is to know when to
draw in the net. To employ watchmen
is rather primitive, and Mr.. Trouve has
devised much better system-at any
rate in theory. His idea is to make
sort of scale, consisting of "a beam pivot
ed to stake This beam has at one end
square net and at the other a tray, i'll
which is placed aweight slightly great
er than that of the square net. An ap-
lropriate mechanism, clockwork or 9TH
erwise, raises up this tray at regular
intervals, say every five or ten minutes,
which gives to the beam an oscillatory
movement. Every time the beam rises
beyond the horizontal position an cleo
trical contact is made connecting at
distance, on the bank or in the boat,
wherever the fisherman is stationed
Whenever there are no fish in this
square net it rises quickly, carried up
by the excessive weight at the other end
Of the beam, and a short interval of
ringing shows that the beam has gone
by the horizontal position without stop
ping there, and consequently there are
no fish. If, on the contrary, the square