ELISHA MITCHELL SCIENTIFIC SOCIETY. 



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to insure the destruction of all eggs and larvfe which may infest it. 

 Cut tobacco should be kept in tightly closed boxes until used. All 

 cigarettes should be packed at the close of the day's work, or closely 

 covered with flannel blankets. As the beetle is said to be a night 

 flier, windows and doors of the warehouse should be kept closed at 

 night. The walls of the building should be kept freshly white- 

 washed, and no dust heaps allowed to accumulate. 



For the purpose of determining the degree of heat to which the 

 insect would be subjected during the process of steaming, I had 

 tests made with the thermometer under three different conditions: 

 First, with the bulb of the thermometer between the hands of to- 

 bacco; Second, with the bulb of the thermometer in among the 

 leaves of the hand; Third, the bulb of the thermometer bound 

 with tobacco as tightly as the portion of the hand which contains 

 the band. Ten tests were made under each condition. The follow, 

 ing table exhibits the results : 



The above tests were made on tobacco of a second grade and the 

 steam was allowed to remain on longer than would answer on bright 

 grades of tobacco. But examining bright grades of tobacco just as 

 it came from the steam chest I think there can be no doubt that the 

 steaming will kill the larvsB and eggs if the tobacco is evenly steam- 

 ed and subjected to the heat for as long a time as will answer for 

 the preservation of the quality of the leaf. Where the sides of the 

 steam chest are low I have noticed that the ends of the " hands" 

 of tobacco often project over the edge and these portions are not 

 properly heated. In turning the tobacco if care was used to place 



