s samples of silk and wool.

=Experiment 48--Test to Distinguish Cotton from Linen=

Apparatus: Fuchsine, ammonia.
Materials: Cotton and linen fabrics.
Reference: _Textiles_, page 240.

_Directions_

1. On account of the high price of linen various attempts are made to
pass cotton off for linen. While it is possible sometimes to detect
cotton by rolling the suspected fabric between the thumb and finger,
the better way is to stain the fabric with fuchsine. If the fibers of
the fabric turn red, and this coloration disappears upon the addition
of ammonia, they are cotton; if the red color remains, the fibers are
linen. The most reliable test is to examine the fiber under the
microscope and note the difference in structure.

2. Test a cheap _linen_ fabric for cotton.

3. When cotton yarn is used to adulterate linen it becomes fuzzy
through wear, and when used to adulterate other fabrics, it wears
shabby and loses its brightness. Linen is a heavier fabric, and
wrinkles much more readily than cotton. It wears better, and has an
exquisite freshness that is not found in cotton fabrics.

4. Describe a chemical test for linen.

5. What is the difference in appearance and wearing qualities of
cotton and linen?

=Experiment 49--Test of Fabric to Withstand Ironing and Pressing=

Apparatus: Hot iron.
Materials: Silk, cotton, and woolen fabrics.

_Directions_

Place the sample over an ironing board and iron it with hot iron
(about 200 deg. F.). Compare the sample immediately with one not
ironed. Remember that many colors, particularly colored silks,
change while they are hot. If the original shade returns when the
fabric has cooled, then the fabric is fast to ironing and pressing.

_Questions_

1. What is the object of ironing and pressing clothes?

2. Is it a good plan to press clothes often?

3. Is there any difference in the effect of the hot iron on the three
kinds of fabrics?

=Experiment 50--Test of Fabric to Withstand Perspiration=

Apparatus: Porcelain dish.
Materials: Silk, cotton, and woolen fabrics.
Reference: _Textiles_, page 243.

_Directions_

1. In addition to withstanding the action of coming in contact with
the human skin, fabrics like hosiery, etc., should withstand the
excretions of the body.

2. To test a fabric for resistance, place the sample in a bath of
dilute acid made by adding one teaspoonful of acetic acid to a quart
of water warme