RESOURCES OF AMERICA, SILK, ETC. 417 



few worms which hatch prematurely ; but principally their extraor- 

 dinary success is to be ascribed to their subsequent treatment of the 

 insects, and particularly to their modes contrived for the purposes 

 of ventilation and the preservation of a high temperature and pure 

 atmosphere, and to the great attention which they bestow on them ; 

 to their constant and night feeding, as well as by day. Forty times 

 during the first twenty-four hours are they fed, and thirty times on 

 the second day, a less number on the third day, and a still less num- 

 ber on the subsequent days. 



Aware of the immense importance of the silk culture to the inter- 

 ests of France, the government of that nation have established an 

 experimental silk-farm at Montgeron, in the north of that country, 

 under the superintendence of M. Camille Beauvais. Already, and 

 previous to the year 1835, by his extraordinary management, had 

 M. Beauvais succeeded in producing thirteen pounds of silk from 

 the same number of silk-worms which, in France, usually produce 

 but five pounds, and in Italy seven and a half pounds, and in India 

 twenty pounds, and even in that cold climate he then expected 

 soon to be able to produce an equal number of pounds. In the year 

 1837 was he enabled to produce 185 pounds of cocoons from 2,000 

 pounds of leaves, a quantity which had been found sufficient for that 

 same number of silk-worms, or for 40,000, which, being of a size so 

 superior, must have been more than sufficient for the production of 

 20 pounds of silk. By him, also, the wants of the silk- worm having 

 been made fully known by new discoveries, and these wants being 

 all supplied, losses from disease are no longer known. 



The silk-worm is a cold-blooded insect, its temperature that of 

 the atmosphere in which it breathes ; its evolutions being wonder- 

 fully quickened by heat, and prolonged by cold. 77 to 84 degrees 

 of heat is its proper element, as now fully ascertained by M. Beau- 

 vais. Combined with this suitable degree of heat and of purity, a 

 certain degree of moisture in the atmosphere is indispensably neces- 

 sary. In their native condition, the silk-worms are exposed to dan- 

 gers continually, either from cold furious storms, or from devouring 

 foes. In such a temperature, and under the benign protection and 

 care of man, they flourish with extraordinary luxuriance, completing 

 their evolutions with great economy of time, of labor, and with aug- 

 mented production, all their labors being brought suddenly to a 

 close. 



The habits of the silk- worm are peculiar to itself, both in regard 

 to the time of taking its nourishment and its sleep. These habits 

 differ essentially from those of the human race. The silk-worm 

 takes no liquid with its food, except only what is contained in the 

 fresh leaf on which it feeds. If neglected, or fed only at long inter- 

 vals, and during the day, even though at such times fed abundantly, 

 a large proportion of the food is thereby wasted. The leaves thus, 

 for a long time exposed, becoming dry, the silk-worms refuse to eat, 

 suffering irrecoverable injuries by day, and also during the long 

 night, both by reason of hunger and tormenting thirst. They suffer 

 doubly, also, from the voracity with which they then devour their food 

 in the morning. But by fresh feeding, at short and frequent inter- 

 vals, by night as well as by day, the food is all devoured, and half 

 the quantity will suffice, none being wasted ; and half the expenses 

 of gathering the leaves and of cultivation being saved ; even less 



