THE MODERN HISTORY OF SILK. 193 



more than by the usual process ; and from eight to 

 ten pfunds of cocoons he obtained one pfund of pure 

 silk, whereas twenty or thirty pfunds had formerly 

 been necessary for the same produce : This method 

 farther enabled a peasant, who could before manage 

 only half an ounce of eggs, now to rear the worms 

 from half a pfund. The means which he employed 

 were chiefly intended to reduce each different process 

 in the eventful lives of these little animals to a regular 

 period, that every one might run his course as nearly 

 as possible within the same time. With this view, 

 he discarded most of the artificial methods which had 

 been adopted for hatching the egg, and, without 

 exposing them to the partial heat of the sun, to 

 warmed pillows, or to the warmth of the bosom, all 

 of which were practised, placed them in a situation 

 where they might be equally affected on all sides by 

 the surrounding atmosphere. He introduced the 

 use of seed mats, which he found, in many respects, 

 superior to paper, for receiving the eggs ; and as all 

 the cocoons were finished together, he was able to 

 destroy all the chrysalids at the same time. For this 

 purpose, he constructed an oven in which he killed 

 the animals in thirty centners of cocoons in twenty- 

 four hours, and on his invention could speak with 

 confidence as to the periods of the changes, in the 

 following terms : " On the 12th of May the worms 

 will begin to break from their eggs ; seven days 

 afterwards the first change of the skin will take place, 

 which will occupy twenty-four hours ; at the end of 

 another week, the second change of the skin will 



