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DISEASES OF SILK WORMS. 
In European climates the caterpillars of the silk- 
worm are liable to many diseases, probably the con- 
sequence of inexperience in their mode of treatment. 
In France and Italy it has long been a common 
practice to give a certain quantity of silkworms to 
the peasantry to be reared, and in such hands, as 
might have been expected, the successful cultivation 
of these was long but imperfectly known ; and it 
was not till the patriotic exertions of Count Dandolo, 
that distinct and settled notions were thought of for 
improving the rearing, and preserving, in a healthy 
condition, this most valuable of all insects. He 
diligently studied the habits of the silkworm in its 
various metamorphoses, and immediately made 
known eyery discovery he had made, either by his 
writings or by giving personal instructions to those 
concerned in the propagation of the worms. He 
published an enlightened treatise on the subject, 
which soon led to the formation of large establish- 
ments in Lombardy. These were named Dandoliéres, 
in honour of this patriotic nobleman. 
Damp stagnant air, and the presence of carbonic 
acid gas, appears to be one of the proximate causes 
