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Through suitable combination of a number of favorable factors it was possible to unify, standardize, and improve the prevalent micro-Carius methods for halogen and sulfur to such an extent that one apparatus and one method of digestion, as well as an identical filtration procedure, can now be applied to the determination of both types of elements. Some of the difficulties inherent in the micro-Carius method have been partially or totally remedied. THE micro-Carius determination of halogen and sulfur possesses numerous advantages, not only as a method to be taught to students, but also as a generally useful analytical procedure. Despite its simplicity, it is most reliable and can be applied to liquids and volatile substances as well as to solids. Furthermore, it offers a high degree of precision because it has no blank and because it involves simple stoichiometric reactions.Prevailing objections to the Carius determination are: the danger of explosions, the long heating period, and the possibility of contaminating the reaction product with glass splinters.An investigation is here described which was undertaken to minimize the above-mentioned difficulties and to unify as well as standardize the apparatus and the procedures. It was found that a combination of the early micro-Carius method of Emich (1) with the conventional micro-Carius method of Pregl (7) aids in overcoming the first two objections while application of the method of differential weighing of the silver halide precipitate in the case of halogen determination, and application of the benzidine method of Guillemet (3) and Weygand and Hennig (9) in the case of the sulfur determination, serve to eliminate the last objection.The apparatus and procedure employed in this work were those described by Niederl and Niederl (6), except where modifications are specifically mentioned. ApparatusBomb Furnace (6, p. 122). Any metal block or cylinder with suitable borings for the pressure tubes can be used. The heating may be done by gas or electrically (4).Pressure Tubes (6, p. 122). The pressure tubes are of straight-walled Pyrex glass without a constricted end. They are 20 cm. long, 9 to 10 mm. in inside diameter, and should have a

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