254 CANKER-WORM. 



ascend the side, and, during her ascent, if the tumbler 

 is turned down and rolled over, she will adhere to the 

 glass, and walk about upon any part of it without any- 

 apparent regard to the rolling of the glass, and appears 

 to walk as well upon the under side of the glass as 

 upon the top. Hence all who have used these inverted 

 tunnels have found them useless, or will, if they con- 

 tinue to use them. 



A circular leaden trough and roof was invented by 

 Jonathan Dennis, Jr. of Portsmouth, R. I. in 1836, 

 and has since been patented. This trough and the 

 roof is made of one strip of sheet lead, about three 

 inches wide, but in the form of the top of the figure 2 

 inverted, with the foot cut off; thus forming a roof 

 and trough of one strip, and then bending it around the 

 tree so as to conform to the shape of the tre^. It is 

 made so large as to leave a space of one inch in width 

 between the trough and the tree. The ends are then 

 soldered together, thus forming a trough completely 

 around the tree, with a roof over it. Three or more 

 nails are tacked into the tree to support it, and the 

 space between the trough and the tree is filled with 

 sea-weed, hay, straw, husks, tow, cotton waste, or any 

 other substance that will prevent the insects from as- 

 cending between the trough and the tree, and is easily 

 compressed by the growth of the tree. These troughs 

 were put on to three orchards belonging to Jonathan 

 Dennis, of Portsmouth, R. I. father of the inventor, 

 in the autumn of 1837, and it has proved to be the 

 cheapest and most effectual remedy ever discovered. 

 The three orchards contained one hundred and fifteen 

 trees, varying in size from three inches to upwards of 

 two feet in diameter. The expense was about thirty- 

 five or forty cents per tree. Five gallons of cheap fish 

 oil, that cost forty cents per gallon, was found to 

 answer for the one hundred and fifteen trees for one 

 year. A very little oil was put into the troughs the 

 l^st of September. After it bad remained several 



