4 BULLETIN 288, U. S. DEPARTMENT OF AGRICULTURE. 
For several minutes only stained seed appeared. After the gin had been running 
5 minutes the sample taken showed 52 per cent of colored seed. At the end of the 
first 10 minutes the sample showed 17.1 per cent of stained seed and after 15 minutes 
7.4 per cent, while at the end of 20 minutes 2.8 per cent of stained seed appeared 
Fig. 1. — Sample of cotton seed taken 5 minutes after the ginning of the second bale had begun, showing 52 
per cent of red seed from the stained roll of the first bale. 
in the sample. The sample taken at the end of 25 minutes showed 0.5 per cent of 
stained seed, and the one taken at the 30-minute period showed 0.1 per cent, or 1 
seed in a sample of 801 seeds. 
When the bale was ginned, the roll was carefully examined and 32 stained seeds 
were found. Not until 10 minutes after the second bale had been started did these 
Fig. 2. — Sample of cotton seed taken 10 minutes after the ginning of the second bale had begun, showing 
17.1 per cent of red seed from the stained roll of the first bale. 
pass out of the gin. No stained seeds were found in the roll box after the ginning 
of the second bale. 
These results indicate that the exchange of seeds in the roll takes 
place very rapidly, practically the entire roll being replaced during 
