MATERIALS AND HOW TO TEST THEM
alkali while artificial silk, a vegetable product will not.
To Distinguish Linen from Cotton: Cotton fabrics are now so cleverly finished to look like linen that even experts are often deceived. If a fabric is all linen or all cotton or is woven with a cotton warp and a linen filling as many of them are, it ts possible to detect the difference between the cotton and linen in the following ways:
(1) By Appearance: Boil a sample of the cloth for fifteen minutes in a soap solution, rinse thoroughly, and dry. This will remove any starch or dressing. Now the linen threads will still present a smooth, lustrous appearance while the cotton will be less smooth and dull.
(2) By Tearing: Linen is stronger than cotton and tears with greater difficulty. The ends of torn linen yarns show very uneven but parallel, glossy fibers, while the ends of torn cotton yarns show rather even, curly, dull-looking fibers.
(3) By Burning: The burning test may be applied for the purpose of observing burned ends of the yarn as previously explained.
Since linen and cotton are both cellulose there is no satisfactory chemical test for distinguishing one from the other. This
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