172 Flow to obtain tt. 
eggs of a different species of fish, and of a different size. These 
can easily be counted in the same manner. The grille may be 
found to contain one hundred rows of eggs, and thirty-five eggs in 
a row, which gives three thousand five hundred eggs on a grille, 
and thirty-five thousand in a box. 
When necessary, several kinds of eggs may be incubated in 
the same box, without any difficulty. Not only may each grille 
contain a different kind or class of egg, but in the case of small or 
experimental lots, which must occur in every hatchery, several 
groups of eggs may be placed quite separately on each grille, by 
simply leaving one row or space empty, to mark the division. 
This is found to be of the utmost convenience, as it often happens 
that these small batches of eggs occur unexpectedly, or on a very 
busy day when there is no time to provide a special corner for 
them. In a box set apart for such lots, they are simply laid down 
at once on the next grille, or part of a grille, in succession. When 
the eye spots appear, they can be moved to any other more 
suitable place, or packed and sent away, if required, right off the 
grille on which they have been incubated. 
One great advantage which attaches to the grille system is, 
that all the eggs can at any time be seen at a glance, and the dead 
or white eggs picked off very readily, and should any sediment 
by any chance whatever have settled on them, during the period 
of incubation, it can be quite easily washed off, by lowering the 
water and using a watering can. This washing, if not done at 
too early a stage, will not hurt them, but will do them good, and 
it is just as well at the same time, to lift each grille with the eggs 
upon it, and clean out the hatching box, for, with the purest 
water something will inevitably settle on the bottom during the 
two or three months occupied by incubation. Even the dust 
from the atmosphere, which is often considerable although invisible, 
settles down, and is continually being drawn in by the water, and 
deposited in the boxes and on the eggs. Of course, in a well- 
ordered hatchery there should be no sediment whatever, in the 
ordinary sense of the word ; and with proper appliances and pre- 
cautions it may easily be kept out. 
Having the hatching boxes thoroughly cleansed is an im- 
portant piece of work, to be done before hatching, and it will be 
