BUREAU OF PLANT INDUSTRY. 283 



of the growers' product through improvement in ginning is un- 

 doubtedly opened up. It has been determined to mstitute speed 

 tests on saw gins, the idea being that as saw gins are used to gin the 

 bulk of the cotton crop it is of fundamental importance to know 

 exactly the effect of different speeds, etc., on the length of the staple. 

 These speed tests will be followed by others relating to the form of 

 the teeth and other details of the machine. 



Preparatory to undertaking the ginning tests a lot of 1,000 pounds 

 of specially picked long-staple cotton and a similar lot of Upland 

 cotton were obtained. A 60-saw standard-driven gin was purchased 

 and installed in the building formerly used as a denatured-alcohol 

 plant. The gin was selected as representing a type widely used and 

 best calculated to give results which will be intelligible to the greatest 

 number of cotton growers. With the aid of the devices for accurate 

 measurement of length of cotton staple a detailed study is being 

 made of the effect upon the fiber of running the gin at various 

 speeds. Other factors which influence the action of the gin on the 

 cotton will be taken up for investigation as opportunity is presented. 



An effort is being made to standardize and record the color of 

 cotton samples by means of several known colorimeters, by the use of 

 combinations of dry colors, mineral fibers, tinted tile, and other de- 

 vices. Within the past year much correspondence and investiga- 

 tional work has been carried on in connection with this effort. 



Paper-plant investigations. — The most important work of the 

 year in connection with the investigations of crop plants which may 

 be used for paper making has been in the practical testing of the value 

 of a food extract which is obtained from cornstalks as a preliminary 

 to their conversion into paper pulp. Preliminary experiments have 

 shown that corn, broom corn, and rice straw yield under hot-water 

 extraction almost the entire nutritive value of the dry material. 

 Feeding tests conducted by the Bureau of Animal Industry with two 

 animals early in the year indicated that the food extract thus ob- 

 tained contained no poisonous substance and produced no injurious 

 effects. As the practicability of utilizing cornstalks for paper mak- 

 ing is closely connected with the value of the by-products which are 

 obtained, arrangements were made to produce the food extract in 

 sufficient quantity to conduct a more conclusive test as to its value for 

 use with different classes of animals. Funds for this work were not 

 available until late in the winter, but Mr. C. J. Brand, of this office, 

 succeeded in installing a plant in Chicago, 111., when enough extract 

 was produced to conduct a feeding test of one month with a herd of 

 20 dairy cattle. This test was conducted by officers of the Bureau of 

 Animal Industry. The report of the Dairy Division of that bureau 

 shows that the extract had a considerable feeding value, but as the 

 test was made at the very end of the stall-feeding period and the 

 animals were kept from pasture two or three weeks beyond the usual 

 time in order that the test might be completed, it is believed that the 

 results are less favorable than they would have been if the test had 

 been made earlier in the winter. The work was also handicapped l)v 

 the quality and quantity of material for extraction which was avail- 

 able at that season of the year. The extract actually used in this 

 feeding test was inferior in quality to that which has been produced 

 in earlier and in succeeding experiments. 



