COMMERCIAL LINT 147 



mercerizing being accounted for in this way. If, there- 

 fore, yarn of a certain count and number of twists per 

 inch is desired, the strength of it will depend almost 

 entirely on the properties of the cotton employed, in 

 respect to the grip which each hair takes on its neighbour. 

 The author has practically no evidence to offer of the 

 kind presented in respect of other characteristics, and 

 our discussion must consequently be very general. 



In the first place, it is obvious that uniformity from 

 fibre to fibre is a prime essential, on account of the 

 weakest link. Uniformity in length must 

 U y * be of some importance, uniformity in dia- 

 meter still more so, with uniformity in fineness, and prob- 

 ably uniformity in twist is the most important of all. Of 

 these four features, the diameter is usually fairly constant ; 

 the length varies from the causes we have already dis- 

 cussed, and if its variation is excessive it can be regular- 

 ized at the card or by combing; variation in fineness 

 we have also discussed under the title of breaking strain, 

 or hair strength, and there thus remains one important 

 component the twist of the lint hair. 



Since the word " twist " has its special meanings in 

 this connection, Jt may be advisable henceforward to 



Convolutions refer to the twist of the fibre as " con ' 

 of the Lint volutions," in order to avoid confusion. 



Hair It was pointed out in Chapter III. on the 



Development of the Boll that the convolutions were 

 caused by the presence of simple pits in the thickened 

 wall, and were thus due to a definite structural cause, 

 and not to any mystic gyrations of the protoplasm in the 



