J 96 PROPAGATION OF TROUT IN AMERICA. 
of the milt can be seen, always taking care to keep the ova submerged, 
the spawn may then be removed to the hatching-ground or boxes ; for 
the artificial spawning bed may be made in a ditch, dug for the purpose, 
and paved, and supplied through pipes with water, as well as in boxes ; 
but experiments have given the preference to boxes, as susceptible of 
forming thereby a stream more equal in flood, volume and temperature. 
In the removal of the ova for a short distance it is unimportant in what 
manner they are conveyed so long as they are not much shaken. In 
transporting to great distances, requiring much care, it is better to carry 
them in bottles of water than in layers between sand or moss, because 
the specific gravity of ova and that of water are so nearly the same as 
to insure against much oscillation. Another advantage of exporting in 
bottles of water is found in the less apprehension of their being dis- 
turbed or injured by Custom-House officers. 
The preparation of the hatching-ground is the same whether it is 
intended to deposit the ova in boxes or in the natural bed of the spring 
or stream. The best substratum consists of a mixture of sand and 
gravel, a couple of inches in depth, upon which stones like the old 
irregular-sized paving-stones should be laid throughout the entire length, 
and the stream should flow equally over the whole. 
In the deposition of the spawn, a portion is taken into any small 
vessel and gently poured upon the hatching-ground, care being exercised 
to distribute it pretty equally. If it should accumulate too thickly in 
places it may easily be scattered by pouring water upon it, when it will 
soon disappear among the small interstices of the paving-stones. No fur- 
ther care is then required, except to keep the stream of water constant and 
pure and protected from injury by frost. The period at which the ova 
may be expected to come to life will be from sixty to ninety days, owing 
much to the temperature of the water. Trout have been hatched in this 
way in less than fifty days, and salmon in less than sixty. 
The annual revenue of the Tay is continually increasing since it is 
being restocked by artificial propagation, and it is now worth 10,000Z. a 
year more than it was before its supply was augmented by its thousands 
annually hatched in fish-boxes. 
The experiment of transporting ova to Australia and hatching them 
there has proved entirely successful. 
By a perusal of the foregoing descriptions for propagating trout by 
the most celebrated and successful fish-culturists, it will be perceived 
that they do not differ much in the modus operandi. Nearly every 
tanner has a spring on his place yielding surplus water sufficient to hatch 
trout in boxes. If he does not wish to go to much expense in erecting 
a dam to form a preserve, he might, at least, hatch the trout in boxes 
and sell them, for they are as ready sale as any product of a farm. Mr. 
Ainsworth, of Bloomfield, N. Y., said : " The original stock (of trout) 
was put in my pond, containing 61 square rods of ground, 14 feet deep, 
►supplied with springs, three years ago, 1,400 in number, age from one 
