2 BULLETIN" 1100, U. S. DEPARTMEXT OF AGRICULTURE. 
scouring of all the wool. Separate determinations of the grease and 
dirt content of each fleece furnish information of great usefulness for 
sheep-breeding studies in connection with their application to wool 
improvement, but the expense of separate determinations for so 
large a number of fleeces creates the necessity for working with 
samples instead of scouring entire fleeces. A sample weighing 
approximately 1 pound is therefore taken from the side of each 
fleece at the time the sheep are sheared. These samples are then 
sent direct to the Bureau of Animal Industry wool laboratory, near 
Beltsville, Md., and stored in a dry room until they are used in the 
Fig. 1.— Wool containers, balance, and record book. The closed container shows the can of raw wool 
ready for shipping and storing at the wool laboratory, Beltsville, Md. Upon preparing the wool for 
scouring, the container is opened and the wool is placed in the basket shown on the balance. A sample 
sheet of the data kept in the record book is shown in Table 7. 
scouring test. Most of the fleeces studied to date have been grown 
on the bureau's experimental range sheep at the United States sheep 
experiment station, near Dubois, Idaho, although fleeces grown at 
the bureau's farm sheep stations near Beltsville, Md., and Middle- 
bury, Vt., are also being sampled for use in this investigation. 
EXPERIMENTAL WORK. 
INDEX FIGURES FOR GREASE AND DIRT. 
Specially designed apparatus has been constructed to remove the 
grease by the use of gasoline, without loss of dirt, and later in another 
apparatus the wool is washed to remove all the dirt. 
Approximately 250 grams of each sample of wool as it comes 
from the storage room are used for the scouring test. The sam- 
