ADULTERANTS IN FABRICS 135 



is as beautiful as silk and wears far better ; farmer's satin has a 

 pleasing luster, and makes a more durable, cheaper lining than 

 either the pure satin or silk which it imitates. 



In the early fall, wool is too warm and cotton is too cool and 

 a " half wool and cotton " material such as flannelette is com- 

 fortable and serviceable; in many climates " half-wool " under- 

 wear is warm enough for all winter. 



Frauds and adulterants in fabrics. Cotton is cheaper than 

 wool or linen, and part-cotton underwear should not be sold 

 at all-wool prices; nor should part-cotton handkerchiefs and 

 tablecloths be sold at all-linen prices. Underwear marked " all- 

 wool " is often 10 to 50 per cent cotton, and sometimes is even 

 90 per cent cotton; collars advertised as all linen are rarely 

 unmixed with cotton. The large dealers easily detect frauds 

 and adulterants in fabrics, but the retail purchaser is rarely 

 conscious of them and often pays double prices. There are 

 several ways to detect frauds in fabrics : one by microscopic ex- 

 amination and another by chemical means. The different fibers 

 have characteristic shapes and lengths and can be recognized 

 by their appearance under the microscope; all-wool material, 

 for example, when examined under the microscope shows none 

 of the flattened twisted fibers which are characteristic of cotton. 



The different fibers differ in composition and react differently 

 to chemicals, and it is possible to test fabrics for purity by 

 chemical means. Cotton, for example, is not affected by caustic 

 soda, whereas wool is dissolved by it. We can tell whether a 

 material is all wool or not by boiling a piece of it for five 

 minutes in a solution of caustic soda. If the material dissolves 

 away completely, it is all wool ; if it dissolves only partly, the 

 portion remaining is the cotton. Silk is dissolved by hydro- 

 chloric acid, but wool and cotton are not. 



A simple test can be made to determine the purity of linen. 

 Cotton retains its original appearance when soaked in olive 



