MALADIES OF THE SILK-WORMS. 81 



the silk-worm will look back and descend once more for 

 the last time to partake of food. Sometimes also during 

 the last period, and previous to the ascent of the insects 

 to form their cocoons, some of them appear languid. 

 Anciently it was found efficacious to introduce fried on- 

 ions to the apartments the pungency of the odor of 

 which, while it induces some to partake with an appetite 

 their last meal, will inspirit others to ascend to their last 

 labors. But in modern times it has been found, that 

 simply removing those silk-worms which thus languish 

 during the last stages, to a warmer temperature, will 

 never fail to inspire them with renewed life. 



Ventilation is very important during the period while 

 the insects are peforming their last labor ; yet in no case 

 is a due and comfortable degree of warmth more needed 

 than while the insect is forming its cocoon, as this ena- 

 bles them to draw forth and to surrender the whole 

 amount of silk which they had laid up in store. 



SECTION XXX. 



MALADIES OF THE SILK-WORMS. 



DISEASES of silk-worms, like epidemics in crowded 

 cities, when they do occur, are generally caused from 

 want of air and space, or from being fed with wet leaves, 

 or from inattention to strict cleanliness, and want of a 

 frequent change or of wholesome air. Whenever any 

 of them appear sickly, they are to be removed to a sep- 

 arate corner or apartment, and placed by themselves on 

 a separate hurdle, called the hospital, that they may not 

 infect the atmosphere, and spread contagion. A very 

 damp state of the air of long continuance being un- 

 wholesome, is to be corrected by flame fires. 



Chloride of Lime, which is now used so extensively 



