OBSERVATIONS UPON COTTON. 413 



e f 



No. of break. Length. Grs. weight. No. of break. Length. Grs, weight. 



1 i'i2 83*0 1 o'95 izS'i 



2 o'66 io8"9 2 0*63 i39'4 



3 o"i5 131*0 3 o"45 188*4 



A good number of instances of second breaks given in 

 the following tables serve to confirm these results, and clearly 

 establish the fact that the cotton hair is strongest at some 

 point lying between the ends ; this point varies for different 

 qualities of cotton, and the length of the fibre which has 

 the maximum strength is of different extent : in some 

 qualities of cotton, such as Sea Island, Queensland, Egyp- 

 tian_, and Maranham, the hairs seem of nearly uniform 

 strength over a considerable length, and in breaking them 

 I get a fair number of cases where the point of rupture 

 lies at a nearly equal distance between the points of sus- 

 pension. In East Indian cottons, on the contrary, the 

 length of hair possessing the maximum power of resistance 

 to rupture seems to be very short indeed — to be nearly a 

 point in fact ; and in nearly every case in the experiments 

 these cottons break at the point of suspension, no matter 

 how short may be the distance between these points. 



It is evident from the foregoing observations that there 

 would not be the slightest use in ascertaining the breaking- 

 weight of cotton hairs without having regard to the place 

 of rupture. I therefore turned my attention to ascertaining 

 the maximum strength of the cotton hairs ; and to do this 

 I had to fix upon what I deemed the strongest part of the 

 hair, and make the distance between the points of suspen- 

 sion very short, as short as one-tenth of an inch for the 

 short staple, and ranging about 0*25 inch for the longer 

 staples. I had no other means of determining the pre- 

 sumed strongest part than by an inspection with the naked 

 eye. I laid the fibre on a black glass plate, and could 

 always see the tapering end, and, coming away from that, 



