174 MISSOURI BOTANICAL GARDEN. 
arranged that when a pull was exerted on the lower pair 
the handles of both pliers became more and more firmly 
compressed, thereby increasing their hold upon the bands 
placed between the jaws. When ready for the test the 
bands were carefully straightened, and the ends were 
placed between the jaws of the two pliers; only enough of 
the band being caught by the pliers to give a firm hold. 
_ Very fine shot was then gradually put into the scale pan 
attached to the lower pair of pliers until the band broke; 
the weight of the shot, plus that of the pan and lower pair 
of pliers, constituted the breaking weight of the bands. 
It was at first thought that the weakest point in the 
bands would be where the bands were fastened to the bag ; 
in order to determine whether this was the case, a number 
of tests were made by attaching weights to the bags them- 
selves, and increasing the weights until something gave 
way. In every one of the preliminary tests the break in 
the band occurred at some point away from the bag at- 
tachment. In other words, it appeared that the weakest 
part of the band was not at or near the bag attachment. 
It was therefore considered to be perfectly fair to cut away 
the bag and to enclose the ends of the bands between the 
jaws of the pliers; the results obtained by breaking hun- 
dreds of the bands bore out these preliminary conclusions. 
It was found that in almost all cases the bands broke at 
some point between the jaws of the two pairs of pliers and 
not immediately at the edge of the jaws. It was further- 
more noted that under most conditions where the bags 
were attached to twigs on the growing tree the break in the 
band occurred ina similar manner to that found when 
weights were attached to the bags themselves. An exami- 
nation of a large number of bands made during June showed 
that with the increase in diameter of the twigs which 
brought about the bursting of the bands on the trees, the 
bursting of the band took place at a point away from the 
bag insertion. 
