December, 1954 ] G. S. MAHAL AND S. JAYARAMAN 265
core is then drawn. To extract cores at these locations the coring tube is held
at an angle of from 35 to 40 degrees from the surface of the bag and the tube is
always pointed along the location line. The arrows on the diagram point in the
directions in which the three location lines are to be drawn, and also indicate the
direction in which the coring tube should be thrust in obtaining the cores along the
given line. This direction of the thrust of the coring tube is always down the centre
line from the mouth, then clockwise, along the side line on the left of the foot of the
bag, and then down the side line on the left of the mouth of the bag. The bag is
to be cored in the specified directions as the clockwise rotation of the coring tube
has a tendency to pull it in towards the main mass of wool, thus counteracting the
tendency of the rotating tube to pull towards the outside of the bag. The authors
report that when the coring tube is held at the 35 or 40 degree angle, at least two
layers of fleeces in each bag can be pierced by each core and wool obtained from
them, and thus it is probable that at least three, more often four, and sometimes
even five fleeces will be sampled with a single thrust of a 24-inch coring tube. They
further observed that for bags shorter or longer than the standard six foot bag used
in the illustration the distance between the coring locations may be altered so that
the pattern of 10 cores per bag can be applied.
The samples that have been thus drawn are placed in a moisture-proof container
in order to eliminate the possibility of changes in moisture content during transit.
The containers then are carefully closed so that no wool will be lost in transit to the
laboratory.
TESTING OF SAMPLES IN THE WOOL LABORATORY
After the core sample has been received in the laboratory, it is accurately weighed
with the help of a sensitive balance. In case the size of the sample being too large,
a subsample may be made for testing in the laboratory. The weighed samples then
go in for sorting. All tags and gross impurities such as pieces of paper twine, heavy
dung locks containing no wool, or heavy patches of paint are removed. The impurities
discarded represent a loss in the original weight and are thus to be taken into
account. The main sort, i.e. the tag-free wool, is then rendered homogeneous by
two or more passages through a wool duster which blends the sample and makes
it uniform. Further it also opens out the sample of wool for a better action by the
scouring liquor. It has been found that it is not necessary to analyse the entire
sample for obtaining accurate results. Enough subsamples of the main sort are
taken and to these are added proportionate representations of the tag sort. These
subsamples of the blended main sort and the tag sort now are ready for scouring
and analysis.
Scouring. Scouring of the sample is carried out on similar lines as in the com-
mercial mill practice. The wool scouring machinery generally consists of a series
of vats or tanks called ' bowls '. The common practice is to use the bowls in sets
of four to three scouring bowls and one rinsing bowl. The wool is run through a
wool opener, then into an automatic feed that delivers the dusted wool into the
first bowl of a four-bowl commercial scouring train. This train is equipped with the
usual heavy squeeze rolls. The first three bowls contain scouring fluid of standard
strength while the fourth bowl contains soft rinse water. Only good textile neutral
soap is used and the water must be soft. The wool is agitated in each bowl. The