ANALYTICAL CHEMISTRY
1862 modifications the apparatus could he aealed up or dorm to collect any desired fraction weight between 0.05 and 10 grams with an accuracy approximately the same 8s that described above. In its present form i t cau he adjusted to deliver fractions anywhere in the range 0.5 to 2.0 grams simply by adjusting the distance between the magnet and the polepiece. Once set, the balanoe using the capacitance proximity paitch should not require readjustment far several months, provided that the polythene surfaces are kept clean. Two of these balances have been used almost continuously for ahout a year without f d u r e . ACKNOWLEDGMENT
The authors would like to acknowledge the kindness of R. A. Weller and V. A. Stephen, Division of Biochemistry and General Nutrition, Adelaide, in suggesting the oil dashpot damping d e vice, and the assistance of W. B. Hall in the statistical determination of the accuracy of the balance. LITERATURE CITED
(1) Boelhommer, C., Riemsdijk. A. J. van, Steenis. J. van, and Waterman, H.J.. Anal. Chim. Acta, 6, 476 (1952). (2) Brimley, R. C., and Snow, A,, J . Sci. Insf?.,26, 73 (1949). (3) Carlander. A. T.,and Gardell, 5..A&o I
