New York Agricultural Experiment Station. 311 



Cover. — In all cases unbleached sheeting was used for cover- 

 ing the frames. In order to have as few seams as possible nine- 

 quarter cloth was used on the twelve-foot and eight-quarter on 

 the eleven-and-a-half foot fumigators. These widths required 

 but one horizontal seam, which in most cases followed the 

 middle rail; they also permitted of an over-lap on the top-rail. 

 For allowing an over-lap on the stile of each door and a slack 

 on two of the hinged angles, to prevent binding when closed, 

 twenty-four-and-a-half and twenty-and-a-half yards in length 

 of the above sizes were used for the sides of the two sizes of 

 fumigators. 



Before attaching cover, all the stiles and top rails of the frame 

 were faced with strips of Canton flannel. This not only 

 strengthened the hinged angles and increased the packing sur- 

 face for doors and top-joints, but also prevented wearing of the 

 cover on the rough frame-work. 



By using three pieces of the sheeting, each a few inches longer 

 and wider than the middle section of the top-frame, two top 

 covers were made as follows: First, one piece was cut length- 

 wise into two strips of equal width. Each strip was folded on 

 itself and the ends sewed together after which it was cut across 

 diagonally forming two triangles. These were sewed to the 

 sides of one of the remaining rectangular pieces completing the 

 cover. In a similar manner the other strip was made into two 

 triangles, sewed to the third rectangular piece and formed a 

 second cover. 



When complete the cover was first fastened to bottom rail of 

 frame and then stretched to top rail and tacked. In each case 

 allowance was made for folds on angles where necessary, and 

 excessive horizontal stretching avoided. 



The only difficulty in attaching cover to top-frame was on the 

 four angles of the sides. Here a gore had to be inserted to 

 allow opening of the top. 



Two grades of sheeting were tested, " Lockwood " nine-quarter 

 wide costing 15|c, and " Palma " eight-quarter wide at 17|c per 

 yard. The latter had a firmer thread and was woven more 



