CUSTOM GINNING IN COTTON-SEED DETERIORATION. 5 



after the last of a patron's cotton leaves his wagon, in order to empty the feed boxes 

 and practically free all of the seed in the roll box from lint before the next lot of cotton 

 enters. 



This brief description is sufficient to make clear the fact that where 

 different varieties are ginned consecutively in the same gins mixing is 

 inevitable unless precaution is exercised. Though the flues which 

 convey the seed cotton are constructed with a view to facilitating the 

 free and rapid movement of the mass, there are usually a few places 

 where a small quantity of seed cotton may catch and remain to be 

 collected by the passing bulk of the next lot. The amount of mixing 

 at this juncture, however, is very slight. Mixing occurs also in the 

 distributing, cleaning, and feeding devices, though this, too, is com- 

 paratively unimportant. The first place at which extensive mixing 

 occurs^ (the place, in fact, where most of the mixing takes place) is in 

 the roll box. Though further mixing occurs in the seed conveyor, 

 mixing in the roll box calls for first consideration. 



MIXING SEED IN THE ROLL BOX. 



Seeds in the roll remaining in each roll box after the ginning of one 

 variety gradually are replaced by seeds of the next variety as it passes 

 through the gins. The replaced seeds are mixed with seeds of the 

 variety being ginned, and together they drop into the conveyor and 

 thence into the patron's wagon. The amount of mixing which occurs 

 in the roll box clearly depends upon the rapidity with which the ex- 

 change of seeds takes place. As a means of determining the rapidity 

 of exchange and the consequent amount of mixing, the method here 

 described was employed: 1 



The seed roll was removed from a 70-saw gin and the seeds were stained red with 

 ordinary dye in order to mark them distinctively. Then they were thoroughly sun- 

 dried and finally returned to the roll box. The roll was packed as near as possible to 

 the density it had before being removed. When the next bale was ginned, samples of 

 the seed were taken every five minutes from the gin containing the colored roll as the 

 seed dropped into the conveyor. The proportion of red seeds in each sample was then 

 determined. The results of these determinations are given in Table I. (See also 

 figs. 1 to 5.) 



Table I. — Extent of mixture in samples of cotton seed taken from the roll of a single 

 gin stand in a battery of three stands at intervals of 5 minutes, as determined at Green- 

 ville, Tex., Sept. 7, 1914. 



Time of sampling after ginning had begun. 



Number and character of seeds in 

 each sample. 



Red seed. 



Total. 



White. 



Red. 





521 

 478 

 527 

 835 

 603 

 801 



250 

 396 

 488 

 812 

 600 

 800 



271 

 82 

 39 

 23 

 3 

 1 



Per cent. 

 52 





17 1 





7 4 





2 8 





5 





1 







1 The writers wish to acknowledge the assistance rendered in this experiment by Mr. George Chandler, 

 whose gin was used in securing the results presented herein. 



