ARTIFICIAL BREEDING OF SALMON. 199 
Where water from a spring cannot be directly ob- 
tained the following plan is often adopted. The scale 
of operations is, however, necessarily more limited. 
A large tub, or other wooden vessel, is fitted with a 
tap. Care must be taken that it shall have previously 
lain a sufficiently long time in water, so that all the 
deleterious substances from the wood shall have been 
extracted. It is then placed on a stand at a sufficient 
height from the ground to allow the case containing 
the hatching-boxes to be placed beneath the tap; and 
they should have a gentle inclination, so that the upper 
end be about half an inch higher than the lower. 
The water, having passed through the boxes, empties 
itself into another vessel, at least as large as the tub, 
and should be so regulated that it shall run out in 
twenty-four hours. The tub, therefore, only requires 
replenishing once in that time. If the water be at all 
muddy, it is well to place a layer of fine sand mixed 
with charcoal at the bottom of the tub. 
Even in a common tea-saucer a great many ova may 
be hatched out. 
The saucer is placed in a deep soup-plate, and a 
couple of moss-stalks laid over the edge in such a 
manner that they shall act as syphons. A constant 
flow of water thus takes place from the saucer* into 
the plate. In about twelve hours half the water from 
the saucer will have run out, so that it will require 
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