The morning call. [volume] (San Francisco [Calif.]) 1878-1895, 1890-08-31

out further preparation this is placed under
pump or under any running stream OF
water. and. is then complete fish-hatching
establishment, in which eggs and fish can
be kept until they are ready to be PLACED in
open waters. All the water is utilized in
passing through the eggs, which appear IN
several layers upon each other. Therefore
the trough NAV, when of suitable size, con-
1ain n great many fish.
Box 4 is constructed of zinc, and consists
of three parts that can be separated from
each other. Compartment b, intOi which
the water flows, is 10 inches long, 10 inches
wide and 10 inches deep; c. with wire-cloth
bottom, is II inches long. 10 inches wide
ment, d. which seals the trough, is inches
long. 10 inches wide, 4 inches deep. The
seal is effected by pressing the three over
flow tubes G into each other
When water flows into compartment b
from faucet q, it reaches the trough from
the bottom through sleeves and d, and
passes off through the overflow e. The
wire cloth is so fine that neither fish nor
eggs can pass through it, there being ff-
teen threads to the inch. As the bottoms
consist of copper wire. they must be thor
oughly coated with the best Syrian asphalt
wax TO guard against poisoning by oxida-
ton.
The catch basin B is sealed by sieve 9.
with the object of OBTAINING any fish that
may have escaped from the trough when
the sieve is removed.
HATCHERY ON SMALL SCALE.
The breeding trough and catch basin to-
gether form a complete fish hatchery on a
small scale. With trout and similar fish
one quart of water per 20 or 40 seconds Is
REQUIRED. while with other fish one quart of
water for every $50 TO $50 seconds Will be
sufficient.
The warmer the water the more of it
must flow through the trough and the fewer
fish should be kept in 1t. a large flow
reduces the danger of warm water. With
the water at so degrees Fahrenheit 1t IS
not advisable to keep more than J000 fish in
the apparatus, and with warmer water the
number should be lessened. When the fish
are observed it will easily be noticea bic
whether or not they are too crowded.
When, as mentioned, 5000 trout eggs are
placed in one trough they must lie in sew
eral layers on top of each other. but this is
not Objectionable. as the water permeatl0g
them from the bottom prevents heavy pres
sure upon the lower layers.
At first, before the eyes of the fish are
visible through the outer covering OF the
egg, every unnecessary disturbance is to be
avoided, as at that period the eggs are very
sensitive and easily killed. The dead eggs
become Opaque and white, and are removed
daily with pair of pincers.
After the dead eggs have been taken from
the top layer it Will be necessary to alter
the position of the eggs in order to remove
the dead ones that lie beneath. To do this
box is slowly lifted and then quickly
pressed down again. The inflowing water
through the sieve bottom will change the
position of the eggs and possibly all the
dead ones may appear on the surface.
To remove all the water from the trough
a rubber Tube is used as q siphon at COM
partment b. If any dirt becomes lodged
among the eggs the water is first removed
from the trough, and the eggs then deluged
with gentle spray of water from the :op.
Should this become necessary before the
eyes are visible the greatest care must be
exercised in doing it.
To exclude light and vermIn wooden
cover is used, which has a sieve-covered
opening at the place where the water enters.
As soon as the fish begin to hatch the
catch basin, Is, is placed in its position to
catch any escaping fish, and these are daily
returned to the trough. At first but few
pass through the overflow, but later on they
escape in great numbers, and the breeding