199 



SAW GINS VERSUS ROLLER GLNS FOR CARAVONICA 



COTTON. 



By C. K. McClelland. Federal Experiment Station, Honolnlu. 



There has been some uncertainty among the various pro- 

 ducers of Caravonica Cotton in Hawaii as to the advisability 

 of ginning- the cotton upon saw gins thinking that the fibre 

 might be injured by so doing. Roller gins of equal capacity 

 as small saw gins cost several times as much. At the Experi- 

 ment Station we have the smaller types of both the saw and 

 roller gins, and the saw gin, which cost less than half as much 

 as the roller gin, has a capacity of about five times as much 

 lint per hour, representing a saving in the cost of the machine, 

 of labor, of gasoline, and of wear and tear upon the engine and 

 gin. In order to find out if the claim "that long staple cottons 

 should be ginned upon roller gins" held true for Caravonica 

 cotton, we submitted samples to the Wonolancet Company of 

 Nashua, N. H., for test. They have reported as follows : 



Saw-ginned cotton. Roller-ginned cotton. 



Amount received 261.4 lbs. 414.12 lbs. 



Picker room returned. . . 248.6 394.12 



Loss 12.8 20. 



Loss in per cent 5.27 4.83 



Card room returned.... 236.5 384. 



Total loss 24.87 30.12 



Total loss in per cent. . 9.12 7.27 



The comparison was carried no further, as the company 

 claimed that practically all the broken fibres would be elimi- 

 nated in these two steps. 



-The company say that the roller ginned cotton with a loss 

 of 7.27 per cent, is about equal to Peruvian which loses 7.25 

 per cent. They also say that it is about equal to Peruvian in 

 roughness, and consequently is of equal money value. They 

 allowed us 18^ cents a pound for the roller-ginned cotton, that 

 being the current price of Peruvian at that time ; but on ac- 

 count of the greater loss in the saw-ginned cotton they al- 

 lowed us but 18^ cents for it. The transportation amounted 

 to about 1.45 cents per pound. 



This report shows but very little difference between the two 

 methods of ginning, but when the relative costs of ginning 

 are considered, the difference will be found to be somewhat in 

 favor of the saw-ginning. And, furthermore, the company 

 submitted samples to the U. S. Department of Agriculture at 

 W^ashington for strength tests, and after the final stage in the 

 preparation of the cotton for yarn the breaking strength of the 

 saw-ginned cotton was found to be 9.36 grammes as against 

 8.19 grrammes for the roller-o-inned. 



