94 ELEMENTS OF APPLIED MICROSCOPY. 
when produced by accidental breakage, are, of course, 
absent, since the whole cocoon containing perhaps 500 
meters of silk is often made up of a single piece. 
12. Analysis of Fabrics—In the examination of a 
fabric a sample should be taken 2-3 sq. cm. in size, or 
large enough to include all the different yarns employed 
in the pattern. The warp and filling threads are then 
separated into their constituents, and one of each kind 
taken for analysis; sometimes there may be a dozen 
different yarns to examine. Under a low power of the 
microscope (fifty diameters) the nature of the fibres is 
determined in the different yarns, taken in the proportion 
in which they occur in the fabric; a rough quantitative 
analysis may thus be made. 
REFERENCES. 
Borrter. Die animalischen Faserstoffe. Leipzig, 1902. 
BorrLer. Die vegetabilischen Faserstoffe. Leipzig, 1900. 
Bowman, F. H. The Structure of the Wool Fibre Manchester, 
1885. , 
Brooxs, C. P. Cotton. New York, 1898. 
Dopce. Descriptive Catalogue of the Useful Fibre Plants of the 
World. Report No. 9 of the U. S. Department of Agriculture 
1897. 
Hannan, W.T. The Textile Fibres of Commerce. London, 1902 
Hassack, C. Wodurch unterscheiden sich die Textilfasern? 
"Leipzig, 1899. 
MattHews, J. M. The Textile Fibres New York, 1904. 
VicNon, L. | La Soie. Paris, 1890. 
Witxwwson, F. The Study of the Cotton Plant. New York, 1899 
