CUSTOM GINNING IN COTTON-SEED DETEKIOEATION. 6 
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 mixiDg 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. 
5 minutes 
521 
478 
527 
835 
603 
801 
250 
396 
488 
812 
600 
800 
271 
82 
39 
23 
3 
1 
Per cent. 
52 
17 1 
15 minutes 
7 4 
20 minutes 
2.8 
5 
30 minutes 
.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. 
