IMPROVEMENTS IN APPARATUS FOR HATCHING AND COLLECTING OYSTER SPAT
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Peter Jensen at the Office of the
Commissioners of Patents on the 25th June 1877. (A communication from
abroad by Harold Nicolai Storm Wergeland, of Christiania, Norway, Lieutenant
General in the Norwegian Army.)
PETER JENSEN, of Chancery Lane, London.
"IMPROVEMENTS IN APPARATUS FOR
HATCHING AND COLLECTING OYSTER SPAT." (A communication from abroad by
Harald Nicolai Storm Wergeland, of Christiania, Norway, Lieutenant General in
the Norwegian Army.)
The apparatus consists in,-.
1. A water-tight reservoir, the clearing reservoir for fresh sea water; this must
be so large that the impurities in the water may get time to fall to the bottom
before the water is led therefrom to the reservoir, which is to be described under
the second head. The reservoir must be so placed that the inflowing water stream
may produce a suitable current and effect a complete renewal, say up to once in 24
hours. It may be filled by means of a pump driven by wind or any other power.
Should the circumstances not conveniently permit the reservoir being placed so
high that the required head of water be thereby obtained relatively to the reservoir,
to be described under the second head, the clear water may be pumped from it up
into a small intermediate tank first.
2. A lower reservoir, the hatching reservoir; the area of this is determined by
the amount of spat it is desired to hatch. It must be placed so high, or be so
arranged that the water from the sea cannot flow in directly at high water. It may.
be about three feet deep, with flat even bottom and even sides. As aforesaid, it
should be below the first reservoir, or the intermediate tank, in order that the
required head of water be obtained.
3. A pipe conduit of suitable size for renewing the water in the hatching reservoir
in the specified time; it has a filtering chamber against the clearing reservoir for
preventing the entry of impurities, or fish, or any other substances from entering the
batching reservoir.
4. The latter is covered in by a house, fitted with windows for opening and shut-
ting; there is also a smaller adjoining room used for a workroom.
5. A heating apparatus for heating the air in the hatching room and the water
therein to a comparatively slight degree. This consists of an open iron vessel,

page_text: containing fresh water proportionate to the enclosed space over the hatching reser-
voir. It may be filled by a feed pipe from a small tank close by. This iron vessel
is heated by means of paraffine or petroleum lamps, with a suitable number of wicks,
some or all of which may be lit as required. Or, if steam can be conveniently
obtained, it may be led directly into the water of the heating vessel; this latter is
covered by a hood of sheet iron, which catches the steam or vapour arising from the
heated water, and from this hood the vapours are conducted to the hatching room,
heating the air enclosed therein to any required extent, and at the same time pre-
venting cooling of the water in the hatching reservoir through the limitation of the
natural evaporation by the entry of the vapour.
6. The pipe conduit which brings the water from the clearing reservoir to the
hatching reservoir is carried coiled through the water-heating vessel aforesaid, in
order to become heated to the required temperature before coming to the hatching
reservoir; the proper degree is obtained by observing a suitably placed thermometer,
and by accordingly regulating the velocity of the passage through the coil by a cock
or valve placed, say, some distance from the heating apparatus.
7. The introduction of the filtered, and, according to circumstances, suitably heated
water from the clearing reservoir into the hatching reservoir through the pipe
conduit, or the arrangement of exit of the latter into the hatching reservoir is such
that the water in the latter is put into an evenly circulating motion by bending the
exit end of the pipe so that the direction of the inlet current is parallel with the
bottom and one of the sides of the reservoir, -some few inches distance from
either.
8. The overflow of the superfluous water from the clearing reservoir is by a pipe,
At its inner
the height of which determines the water level in this reservoir.
mouth it has a filter reaching down to the bottom of the reservoir and the upper
edge of which is over the water level. This filter may be cylindrical, and is covered
with wire gauze; it is so wide that the water in sufficient quantity can filter through
the spaces in the gauze while the spat, freely floating about, is prevented from passing
through the spaces, the spat also avoiding to fasten itself to objects of that sort.
The outlet of the pipe is open for the free outflow of the water.
: 9: The bottom of the hatching reservoir is coated with objects suitable for the
collection of the oyster spat (the best cultch); the sides may also be covered with
objects which experience have proved to be suitable. The reservoir is charged to a
.suitable degree with different objects for catching the oyster spat, such as have by
experience been found suitable for that object. Mother oysters in suitable number
are placed on the bottom and on the appliances suitable for collection of the
:spat.