SILK-WORMS. 
73 
Boxes containing the same quantity of eggs, and 
even smaller ones, lost nearly as much in weight. 
In five days, the evaporation of the eggs in the 
stove-room, is 13 grains per ounce ; in eight days 
37 grains ; and in ten days, which is till the period 
of hatching, 47 grains. Thus one-t'welfth of the 
weight of the egg evaporates previous to hatch- 
ing. The shells or husks of 24 ounces of silk- 
worms gave the following weight: 
A small box of eight ounces, gave 1020 grains of busks. 
Ditto six ounces, gave 724 ditto ditto. 
Ditto five ounces, gave 504 ditto ditto. 
Ditto 1 five ounces, gave 54S ditto ditto. 
2796 
The average weight of the shells or husks is thus 
equivalent to about l-5th of the weight of the eggs. 
To make one ounce of picked eggs, there should 
be for an average weight 39,168 eggs. I ob- 
served, with some surprise, that there was little 
difference in the weight of eggs belonging to 
above twenty different persons. 
I have had the patience to count many hundred 
thousand eggs, in hopes that it might be useful in 
the art of rearing silk-worms. The best eggs, 
when weighed, afforded no more than 68 eggs per 
grain. And the inferior quality of eggs did not 
afford more than 70 eggs per grain. 
I will only add here, that about 360 good co- 
coons weigh one pound and a half. That those 
who suffer no loss, either in the eggs, or in young 
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