certain Diseases of the Silk- Worm. 23 



ing into the vessel a small quantity of acid, in proportion 

 as the vapour diminished ; he continued this operation 

 almost a quarter of an hour, but restrained the evolution 

 of the oxygenated gas within proper limits, which the 

 delicate nature of the insect seemed to require ; and 

 gave room, as much as possible, to the circulation of 

 the air, through the doors and windows. In two days* 

 says Sig. Paroletti, the disease disappeared, the Worms 

 of this room went to the bosco (the name given by the 

 Italians to the bundles where the Worms spin) happily, 

 and had complete success in their operations. It is wor- 

 thy of remark, that the collection of silk was more 

 abundant, in proportion to the quantity of Worms. In 

 short, many bozzoli (balls or codes of silk), in another 

 room, better exposed, where, notwithstanding the dis- 

 ease had not appeared at the time of their going to the 

 bosco, were found of a.black tint, and the chrysalis had 

 advanced to a putrefactive state ; there was nothing 

 similar to this in the rooms, which had been disinfected 

 by fumigation, it convinced the author of its salutary ef- 

 fects; whether by purging the air from mephitic mias- 

 ma, or by re-animating the vital strength of this little in- 

 sect, was not determined. 



A second attempt was made in the following year, 

 with the same success, in a chamber, where there were 

 some hundreds of Silk- Worms attacked by a disease, which 

 caused them to become lucid and of a yellow colour. 

 Tht effects of the gas was limited by holding open, near 

 to them, one of the portable disinfecting vials, which 

 Citizen Boluay prepares: almost all the worms went to 

 the bohco, and made excellent balls of silk. 



