218 [Senate 



The results good. In 1839, a very cool season, I fed two crops, and 

 different kinds of worms. They were generally eight weeks before 

 they spun, but very healthy, and spun good cocoonss. 1840, I fed 

 three crops, of different hatchings; the season was warm and the worms 

 did well generally ; but one brood, that was in its last age about the 

 middle of August, when we had a week of excessive hot weather — the 

 thermometer ranging from 85*^ to 96°, with hot nights, and on the se- 

 cond day of this hot weather, for the first time, I observed the appear- 

 ance of the yellows. Believing it to arise from too excessive a degree 

 of heat for the worms at that age, 1 ventilated I he room, so as to give 

 them the whole atmosphere, night and day, removed the diseased and 

 dead w^orms. kept them clean, and arrested the disease, until the weather 

 became cooler, and lost but a small part of the brood. They produced 

 excellent cocoons. I was the more confident that the constitution of 

 the silk-worm, in or near its last age, could not long endure a heat of 

 85 to 90 degrees, from the fact that I had on forms in the same room, 

 a brood or crop of some 30,000 between the 2d and 3d moulting, and 

 they passed the 3d moulting during this same hot weather, with per- 

 fect safety, although not more than ten feet from the hurdles on w^hich 

 were the diseased worms. Not one of this crop was affected with the 

 yellows, or other disease. And I will here observe, that I have never 

 seen or known this disease to attack the silk- worm except in or near ita 

 last age; and not then, except there is a continued heat of several suc- 

 cessive days, of 80 degrees and over. I will also here observe that at 

 the time above mentioned, I had a neighbor that had a crop of silk- 

 worms that had done finely until this hot weather commenced ; some 

 had begun to spin, but he could not increase the ventilation of his 

 room, and he literally lost his whole crop, and this was the case of all 

 as far as I could learn, who had silk-worms in their last age at that time ; 

 which discouraged many new beginners. In 1841, 2, and 3, 1 have 

 fed silk-worms, and with general good results ; and whenever anything 

 has taken place unfavorable, I could trace it to a satisfactory cause. In 

 1841, I had a family or crop of over 20,000, which would not mature 

 until about the lOth of September. I fed them until after the 2d moult- 

 ing on leaves of the morus multicaulis, and then about a week on the 

 leaves of the white mulberry, of the Florence variety, and they were 

 perfectly healthy; when, for two days I was forced to resume feeding 

 on the leaves of the multicaulis. The result was, that the next day 

 after resuming the feeding on multicaulis, I observed many that were 

 sick, and vomiting, which increased the 2d day, and many were al- 

 ready dead. The third day I resumed feeding on the white mulberry, 

 and changed the worms for several successive days. Notwithstanding 

 every care, I lost the major part of the crop, and evidently by feeding 

 for two days on two succvlent leaves. This was the greatest loss of 

 silk-worms that f have experienced during all my feeding. I have al- 

 ways used the ground-floor of a wing of a dwelling-house, or a cham- 

 ber to feed in. I have not generally regulated the temperature by arti- 

 ficial heat; but at times, in some seasons, I have found it necessary, 

 and have done it with success, and particularly when the nights and 

 mornings were so cool that the worms remained torpid. The present 

 year 1 fed a small crop in a chamber where I had no means of regulat- 



