Automatic combustion methods for the determination of sulfur, chlorine, bromine, and iodine are described. By the use of a modified Grote combustion tube in combination with volumetric procedures, satisfactory micromethods have been developed. The indicators used are dipotassium rhodizonate lor sulfur, dichlorofluorescein for chlorine and bromine, and starch solution for iodine. The largest standard deviation for these methods was found to be ±0.14% for sulfur, ±0,10% for chlorine, ±0.17% for bromine, and ±0.15% for iodine in the group of compounds analyzed.Methods are also described for the acid-base titration of sulfur (in the absence of acid-forming elements other than carbon) and for the determination of traces of chlorine employing a turbidimetric estimation of the chloride ion.

The precision of the method was at first astonishing, in view of the inability of Breh and Gaebler (1) to titrate a similar precipitate with permanganate because of the silver present. Runs on known amounts of potassium were reproduced within an average deviation of 0.02 ml. Table I. Recovery of Potassium from Potassium Sulfate Solutions(Standard K2SO4 solutions: Stock, containing 1.0 mg. K per ml., prepared by dissolving 0.2227 gram of pure dry K2SO4 in 100 ml. of distilled water.Working (1) containing 0.10 mg. K per 5.0 ml., (2) containing 0.20 mg. K per 5.0 ml.) Potassium Added0 Potassium Recovered Mg.Mg.

THE use of microscopy in the textile field is not new, since it is well known to the textile technologist. It has been used extensively for the study of the structure of fibers and fabrics and to some extent in a study of dyeing, printing, and finishing. It is possible to identify the fibers to be colored, examine the damaging effect of treatments, study the penetration of dyes, investigate causes of color defects, study methods for improved color application, observe the effects of fiber finishes, etc. In these studies, the microscope, if operated by qualified personnel, can be a useful tool in the evaluation of quality of the textile and thus make it possible to produce a satisfactory product at the lowest possible cost. Fiber MorphologyIn modern dyeing the colorist is confronted with the application of color to fabrics containing many different fibers. Since no class of dyes has been discovered which is applicable to all fibers, it is necessary to know the fiber or fibers which make up the material to be dyed so that the dyes having the most satisfactory properties can be chosen. Dye identification stains, and such tests as burning to detect characteristic odor, are often useful. However, in many cases use of the microscope is desirable for definite confirmation and quantitative estimation of fibers in mixtures. In addition to identification, microscopical examination can be employed to determine the fiber size, fineness, or denier, and the quality of the fibers under inspection. For example, the amount of mature and immature cotton can be determined by viewing in polarized light [41 ] , the presence or absence of a skin on rayon may be ascertained [21 ] , and the presence of pulled and mechanically damaged wools can be detected [47].

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