of the Fishery Board for Scotland. 109 
on the beach itself, being of fireclay pipes, which have answered very well, 
and have only given rise to trouble on one occasion, in the course of last 
spring, when a section had to be renewed. The end of the inflow consists 
of a length of an iron pipe, terminated by an upturned part, raised about 
two feet from the bottom, and covered with a large shield of wire-netting. 
Tnis arrangement is to prevent the access of sand, debris, and weeds as far 
as possible. The outflowing water escapes by a flap-valve at the end of 
the pipe, beneath the up-turned portion, and on the same level as the rest 
of the pipe. 
The water on entering goes into a small compartment of the pond called 
the filter chamber. Here it passes up through wire-netting, which may 
be of any dimension of mesh, and, if necessary, through filtering material 
There are two slide-valves, one controlling the connection of the filtering 
chamber with the sea and the other the connection between the chamber 
and the pond. The water may be admitted direct to the pond, or it may 
be pumped from the filter chamber to the reservoir tank. 
The latter (a, fig. 1, pl. VI.) is built of concrete on a natural mound 
lying between the new site and the spawning pond. It is a strong tank, 
29 feet long, 7 feet high, and 20 feet in breadth, and capable of holding 
15,570 gallons of water, It is from it that the supply to the hatching 
apparatus and to the tanks in connection with the laboratory is obtained 
during the night. It can be filled by the pumps in about two hours and 
a quarter. A pipe, carried through the concrete wall at the bottom, 
leads the water to the hatchery; another carries a supply to the tank-house 
for laboratory work, and another allows it to pass into the spawning pond. 
The pipe going to the tank-house is shown in fig. 2, pl. VI., at e, and the 
pipe entering the pond is on the left of the letter e, and close to it. The 
water from the reservoir may be filtered or unfiltered; the iron pipe 
which passes through the wall of the tank is connected with a flexible 
hose, the end of which enters a floating box, so arranged that the supply 
is drawn from the surface, where there is less matter in suspension, and 
through flannel or other material. 
The hatching-house, as now arranged, measures 493 feet in length by 
24 feet in breadth, part of it being 28 feet wide. The height of the 
building is 18 feet; it is lighted by 16 windows, and is painted inside in 
light tints, the walls being pale green and"the ceiling white (fig. 1, pl. VII.). 
Two material improvements were made in the re-erection of the build- 
ing. A concrete floor, suitably sloped, replaces the previous wooden floor, 
and is a great advantage, since the water which is spilled over the floor 
when the work is going on now flows away into convenient gutters, which 
are connected with the drain going to the beach. The hatchery is much 
drier now, and the appearance improved. A large sink, supplied with 
fresh or sea water, has been erected in the middle of the floor for washing 
hatching boxes, &c. The other chief improvement consisted in taking in 
the filtering apparatus, which were previously outside, and this was effected 
by extending the walls and roof, the gable being put further out. For the 
“tumbling-boxes,” which impart automatically a certain movement to the 
hatching boxes, two brick chambers have been built below the concrete 
floor, each 4 feet 4 inches by 4 feet 8 inches, and 34 feet in depth. One 
is in connection with the waste water from each side of the hatchery, that 
is, the water which leaves the hatching boxes and is carried to the pond. 
The filters consist of one large box, 8 feet by 4 feet and by 2 feet deep, 
and several smaller boxes, which receive the water from the larger one. 
All these are fitted with filters of flannel or blanketing, on frames covered 
with wire-netting and made tight by rubber bands; all the water which 
comes from the reservoir must pass up through them by pressure, and it 
