sir. K-W 0 R MS . 
255 
are exposed to a higher temperature than that 
in which they came forth. The surface of these 
insects is extensive in comparison to their weight, 
as the surface of six barrels, of one cwt. each, will 
be greater than that presented by one barrel, of 
six cwt. The strong evaporation promoted by 
heat affects their delicate organs too strongly, 
particularly before they have eaten. 
4. When, on the contrary, the worms, being 
just hatched, are exposed for any length of time 
to a much colder temperature than that in which 
they came forth. Were it only for a few hours 
the evil would not be of much consequence, but 
if it last a day or more, the insects get weaker, 
feed little, and have great difficulty in recovering. 
Those persons who hatch eggs for othei's, and 
have not warm places in which to put the silk- 
worms in as fast as they are hatched, run a great 
chance, if the spring is unfavoui’able, of injuring 
whole broods of silk-worms, as I witnessed in the 
cold spring of 1814. 
I observe that the silk reservoii-s are the fii’st 
oi'gans affected by the diseases proceeding from 
the causes I have been describing. If they ai’e 
deeply contaminated, the silk-worm will always 
be infirm, and die befoi-e the completion of its 
natui-al term of existence. 
The alterations and diseases of which I have 
spoken, cannot occur if, — 
