120 THE DEVELOPMENT OF KAW COTTON 



still be composed of samples showing various properties. 



If, on the other hand, the intervals between the pickings 



were shortened, and the pickings kept sepa- 



Classincation rat much greater un if O rmity could be 



of Pickings. 



attained it might even be permissible to 



mix certain pickings together; thus, in the series here 

 discussed, a much more level sample is produced by 

 mixing September 1, 2, 3, 25, 26, 27, and October 9, 

 than by picking all the bolls which ripened between 

 August 22 and 29. Such mixing would not be permis- 

 sible for the unskilled cultivator, but there are some clues 

 upon which he might guide his conduct. 



For example, if strain No. 77 were being cultivated at 

 Giza, and if short-period picking were practicable, and 

 if the irrigation intervals had been adjusted to bring 

 strength and length fluctuations into step, then the 

 grower would keep all the bolls which opened between 

 the sixth and twelfth days after each watering separately, 

 and either mixing them or keeping them separate, accord- 

 ing to opinion obtained, would dispose of them as the 

 highest grade of his product. 



Discussion of this matter brings us to the ultimate 



analysis of "regularity." If pure strains are cultivated, 



and if pickings are so taken as to include 



Uniformity Qnl t j lose ^ays on which the cotton is all 

 in Cotton. J 



alike from day to day, there remain only 



two more ways in which the sample can be made irregular. 

 These two are, firstly, individual fluctuation from boll to 

 boll and from plant to plant, and, secondly, variation in 

 lint properties of various parts of each seed involved. 



