of the above professors at Cleveland the best.
To these gentlemen the country is much indebted for the knowledge
derived from their zeal and success in fish culture. At the head of a
spring they built a house eight by twelve feet; in the end of the house
toward the spring they made a tank four feet wide, eight feet long, and
two feet deep; this was made of plank. Water enters the tank through a
hole near the top, and escapes through a similar one at the other end,
and is received into a series of ten successive boxes, each one a little
lower than the preceding one. These boxes were eighteen inches long,
eight inches wide, and six inches deep. These were filled to the depth
of two inches with clean sand and gravel. The impregnated eggs were
scattered among the gravel, care being exercised not to have them in
piles or masses. Clean water is necessary, as the sediment deposited by
impure water is very destructive to the eggs. If it be seen to be
collecting, it should be removed by agitating the water with a
goose-quill or soft brush, and allowing it to run off; continue this
till it runs clear. But there is a method of preventing impurities in
spring-water, that will be always effectual: just around on the upper
side of the spring make a tight fence two feet high, and it will turn
aside, and cause to run around the spring, all the water that may flow
down the rise above in time of rains. The house being near the head,
there will not water enough get into the spring, in any storm, to roil
the water. On the side of the boxes where the water escapes should be
wire-cloth, so fine as not to allow the eggs to pass through. Such an
apparatus will be perfect. This great care is only necessary for trout.
All other fish worthy of cultivation, will only need spawning-beds on
the margin of their pond. A convenient hatching apparatus is a number of
wicker-baskets, fine enough not to allow the eggs to pass through, set
in a flume of clear running water.

The method of Gehen and Remy, the great fish-cultivators of France,
whose efforts and discoveries have contributed more to this science than
those of any, if not of all other men, was to place the eggs in
zinc-boxes of about one foot in diameter, having a lid over them--the
top and sides of the boxes pierced with small holes, smooth on the
inside; these boxes were partly filled with clean sand and gravel, and
set in clear running water. M. Costa's method, at the college of France,
is to