158 
THE ART OF REARING 
which the silk-worms were removed, furnishes 
them with an abundant meal ; the other ninety 
pounds of sorted leaves should be divided into 
two meals, which should be given them every 
six hours. In giving the first meal, care must be 
taken to straighten the lines of the strips on the 
hurdles, by sweeping any straggling leaves or 
worms into regular order with the little broom. 
At the third meal, the strips should be widened 
a little. Should there be too many worms in 
some parts, they should be taken to cover the 
barer parts of the wickers. 
The silk-worms appear tolerably strong this 
first day. 
At the fourth age, 900 pounds weight of 
leaves were distributed on the wickers, and the 
litter of this age weighed 300 pounds. The 
silk-worms have thus derived 600 pounds weight 
of the substance, including the loss by evapora- 
tion. The excrement weighs about 93 pounds. 
If the exterior temperature be mild, and little 
different from that of the laboratory, it might be 
left open while cleaning, and thus admit on all 
sides a free current of air ; and also burn shav- 
ings to make a blaze, and this is particularly 
necessary, when the cold or dampness of the 
weather precludes opening all the apertures of 
the laboratory while cleaning. In cases of cold 
and high winds, the upper and lower ventilators 
may be kept open, which will renew the air as 
