74 
THE ART OF REARING 
worms, might obtain from one ounce of eggs a hun- 
dred and sixty-five pounds of cocoons ; and what- 
ever less is derived from this quantity may plainly 
shew the exact amount of loss and damage. 
One ounce of eggs, composed of 576 grains, is 
reduced to 413 grains, deducting 47 grains, lost 
by evaporation, and 116 grains in the weight of 
husks. The 413 grains are thus equal in weight 
to 39,168 young worms. At this i - ate 54,526 
young worms, newly hatched, are required to form 
the weight of one ounce. 
Attentively examining the different facts relative 
to the varieties in the quality of eggs, I have con- 
vinced myself, that particularly cold weather, such 
as we had in 1813, at the time of the birth of the 
moth, much injures the impregnation of the eggs. 
Among all the different qualities of eggs I then 
examined, I found not one that did not contain in 
weight a proportion of x and even i of yellow and 
dingy, or unimpregnated eggs. I carefully chose 
5000 yellow eggs, and 5000 red eggs; they had 
all a specific weight greater than water, as they 
sank when washed. I had them put into a box, 
and placed in the stove-room, with the other boxes 
of eggs; one single worm alone was hatched from 
a red egg. They remained filled with matter ; 
but as they were not impregnated, they could 
produce no worms. They diminished more in 
weight than the impregnated eggs. 
