On the Health of Silk -Worms. 323 



relaxing influence of the south wind. It was natural, there- 

 fore, to suppose that an agent, which, in destroying the 

 deleterious miasmata suspended in the air, likewise, diffuses 

 that vital air, the first element of our existence, should be 

 particularly favourable to the breeding of silk-worms. The 

 use of oxygenated muriatic acid answers this purpose effectu- 

 ally. The disengagement of this gas, (the manner of which 

 is now sufficiently known) two or three times every day in 

 the apartment destined for the keeping and feeding silk- 

 worms, will be attended with very important advantages. 

 The absence of the offensive smell, dryness of the layers, 

 the appetite, activity, and equal march of the worms, are 

 usually the first symptoms of its salutary effects, of which 

 the greatly increased richness of their products is the fortu- 

 nate result." M. Vincens relates the following experiment : 

 Having had a large and full chamber of worms suffocated by 

 the negligence of their attendants, who, not perceiving a 

 sudden change in the temperature, imprudently continued 

 the fire ; a total loss is always the consequence of such ac- 

 cidents, as the few worms which do survive are so debili- 

 tated, that they soon perish in their turn amidst heaps of 

 dead. In this case M. Vincens had recourse to the disin- 

 fecting fumigations Tvith oxygenated muriatic acid, which he 

 doubled and even trebled, till he had the pleasure of seeing 

 all those worms which were not, familiarly speaking, burnt, 

 resume their pristine health, and finish their business of spin- 

 ning with the greatest success. By these means he succeeded 

 in saving about the half of his worms. The value of this 

 discovery will be best appreciated by those who have either 

 for amusement or profit occupied themselves in rearing silk- 

 worms, which unquestionably might be bred in this country 

 in quantities sufficient to prevent any disagreeable scarcity of 

 the useful article of silk. These fumigations are likewise so 

 simple, that any person, taking two parts of common 

 salt, adding one of black manganese, and putting them in 

 an earthen pan and pouring on as much oil -il vitriol mixed 

 with a little water as will moisten them, may produce this 

 gas, so salutary to the worms. 



POWER- 

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