SILK-WORMS. 
259 
4. If, in addition to the above causes, a wet 
season should occur, and the leaves be very wet, 
and they should be given to the silk-worms before 
they have been sufficiently dried, it will, in all the 
above ages, quicken the fermentation of the 
litter, and augment the dampness of the labo- 
ratory. In this state, should there not happen 
to blow any drying north winds, to expel the 
moisture, the constitution of the silk-worm 
would, in a short time, be affected, as I observed, 
the case to occur in 1814, a year in which the 
worms of several laboratories almost all perished. 
These losses never can happen, — 
1. When the worms are evenly distributed in 
space proportioned to their numbers, as I have 
frequently repeated in this work. (Chap. XIV.) 
2. By renewing the air, and keeping the la- 
boratories dry, by the means I have indicated.. 
3. And if care be taken to gather the leaves 
some time before they are wanted, and when they 
are wet, to have them thoroughly dried before they 
are siven to the silk-worms. 
I might have added, as one of the causes of 
disease in the first age, and even in the second 
age, when the leaves are blighted or yellow in 
consequence of the badness of the season; but 
this is a case of rare occurrence, particularly if 
care is taken not to allow the worms to come 
forth until the season seems favourable, and the 
