MEASURING TEEES. 



33 



needed, another one is painted on each side of this line at a 

 distance of about 36 inches for tents 60 feet or less in diameter 

 and from 42 to 48 inches for tents of larger size. These two lines 

 should not be more than 1 inch in width, so that they can be 

 readily distinguished from the wider median line. The exact cen- 

 ter of the tent is now located by measurement on the median line 

 and the corresponding points on the two outside lines are marked. 

 Taking into consideration the smallest tree that the tent probably 

 will ever be used to cover, distances are measured on these three 

 lines, in both directions from the center, so that parallel lines about 

 4 inches long, h inch wide, and 1 foot apart can be made across 

 each longitudinal line, beginning 1 foot from the edge of the tent 



Fig. 7. — Tent marked to aid in estimating dosage, in position for fumigation. (Adapted from 



Marlatt.) 



and making the lines in succession toward the center. After making 

 a given number of these cross lines on each longitudinal line, the 

 number in each case equal to the distance from the middle pomt to 

 the cross line is painted on with conspicuous figures. (PI. Ill, figs. 

 3, 4, 5, and 6; PL IV, fig. 1; PI. VII, figs. 1 and 2.) If properly 

 marked according to these directions, the corresponding cross lines 

 on the three parallel longitudinal lines should be marked with the 

 same number, as shown m figure 6. Wlien the tent is exactly cen- 

 tered over a tree the reading at the ground on both sides of the tent 

 will be the same. Ordinarily, however, when the tent is so placed 

 that this line passes as nearly over the center of the tree as it is 



