THE MODERX HISTORY OF SILK. 181 



supply the wants of ten thousand caterpillars. She 

 tried to feed worms on all the different leaves of a 

 large and variously stored kitchen garden, but they 

 would not eat any but lettuce and spinnage, and they 

 perished on these in a very short time, owing, she 

 imagined, to their moisture and coldness. 



The criterion to judge of the goodness of silk is, 

 by the height of the gum ; and that of Miss Rhodes, 

 in that respect, outstript Italian silk. She accounted 

 for it in this way, that in Italy the chrysalis soon 

 bursts, and the imago is destroyed to prevent them 

 eating their way out of the cone, in which case they 

 are sure to injure the silk ; and, to effect this, they 

 are placed in heated ovens. In Britain, where 

 progress is slower, there is sufficient time to wind 

 off the silk, without killing the chrysalis. Miss 

 Rhodes frequently wound the cones out of boiling 

 water, placing them afterwards on dry paper, and she 

 always found that the chrysalis was uninjured by this 

 mode of treatment, and that the moth was regularly 

 transformed at its proper time. 



If, therefore, the chrysalis can bear so great a 

 degree of heat as boiling water, it is obvious that 

 the warmth of the ovens, and the length of time it 

 is necessary to keep it there, to ensure its destruc- 

 tion, must greatly injure the strength and glossy hue 

 of the silk. But this is not all, for in Italy they 

 suffer the moth to eat its way out of the largest cones, 

 in order to have eggs from the most healthy, and 

 thereby lose all the silk in those cones. Here, the 

 silk may be gathered, as well as the moth preserved ; 



