FEBRUARY 15, 1937
ANALYTICAL EDITION
Assoc. Official Agr. Chem., Official and Tentative Methods of Analysis, 3rd ed., 145 (1930). Reckmann, 2. Untersuch.Nahr. u. Genussm., 2, 709 (1899). Bedford, C. H., and Jenks, R. L., J . SOC.Chem. Ind., 26, 123
(1907). Bleyer, B.,Diemair, W., and Frank, E., 2. Untersuch. Lebensm., 66, 389 (1933). Dudley, W. L., J.Am. Chem. SOC., 30,1271(1908). Fellenberg, Th. von, Chem.-Ztg., 34, 791 (1910). Fellenberg, Th. von, Mirt. Lebensm. Hyg., 1, 311 (1910). Fellenberg, Th. von, and Schuppli, O., Ibid., 9, 141 (1918). Komarowsky, Chem.-Ztg., 27, 807,1086 (1903). Korenmann, J., 2. anal. Chem., 88, 249 (1932). Lunge, G.,“Technical Methods of Chemical Analysis,” pp. 726 ff., New York, D. Van Nostrand Go., 1914. Mann, E. A., and Stacey, C. E., J. SOC.Chem. Ind., 15, 1125
(1906). Marquardt, L., Be?., 15, 1370 (1882).
95
(16) Mitchell, A. S., and Smith, C. R., U. S. Dept. Agr., Bur. Chem. Bull. 122, 25 (1909). (17) Muller, C., ”Determination of Fusel Oil in Alcoholic Liquors,” dissertation, Leipzig, 1911. (18) Rose, Stutzer, and Windisch, Arb. kaiserl. Gesundh., 5, 391 (1889). (19) Ruppin, E.,2. Untersuch. Lebensm., 66, 389 (1933). (20) Savelle, Mohler, and Saglier, Fremy’s Encyclopedie Chimique, P. 285 (1890-91). (21) Schidrowitz, P.,J . Am. Chem. Soc., 29,561 (1907). (22) Schidrowitz, P.,and Kaye, F., Analyst, 30, 190 (1905). (23) Tolman, L. M.,U. 8. Dept. A g r , Bur. Chem. Bull. 122, 25 (1909). RECEIVED October 5, 1936. Presented before the Division of Agrioultural and Food Chemistry at the 92nd Meeting of the American Chemical Society, Pittsburgh, Pa., September 7 to 11, 1936. This paper is part of an investigation carried on by the Research Department of the Consolidated Gas, Electric Light and Power Company of Baltimore and Penniman & Brownc.
Support for Perforated Platinum Crucibles WILLIAM M. THORNTON, JR., Loyola College,
AND
T
JOSEPH G. SMITH, Johns Hopkins University, Baltimore, Md.
HE need has long been felt for a holder that would sup-
port both the cap and the receptacle proper of the Gooch filtering crucible (1) during a high-temperature ignition. If a triangle be selected to accommodate the cap, the small system is somewhat lacking in stability; whereas, if a larger triangle be chosen, the hot cap (especially during the early stages of the heating) may fall to the work table. Using two rings, placed one above the other, becomes impracticable for small crucibles, since with ordinary rings the upper and lower triangles are located too far apart. The contrivance here depicted, after a design by one of the authors (J. G . S.), has been found to serve admirably and permits the treatment of perforated crucibles differing considerably in size.
Construction An 8.3-cm. (3.25-inch) cast-iron ring, R, is notched at three places equidistant from one another, preferably at the points where the little projections extend inward, so as t o produce six level spaces about 5 by 10 mm. each-three above and three below. At the approximate center of each of these rudely rectangular areas a hole is drilled and subsequently threaded, and into this opening sleeve SI, the up er and slightly larger third of which (exclusive of the cylin&ical head) is reciprocally threaded, is fitted by turning downward until the head rests snugly upon the flattened part of the ring, where it is firmly held by tightening nut N . The slender rod, P, with grooved head rests loosely in the sleeve and naturally falls to the lowest level permitted by screw Sc. This long thin screw is without taper, terminates in a rounded and grooved head, is threaded throughout its length, and a knurled nut is attached t o it by virtue of its own threads. Sleeve 81, starting at its lower end, is threaded for a short distance, where its internal diameter is a little less than that of the remaining portion. these threads control the up-and-down move. ments of screw Bc. The rod, sleeve, and screw were machined from mild steel.
Manipulation The smaller triangle, Tz, lies on ring R and the twisted ends of the larger triangle, TI,rest in the grooves of the three rod8, P . By turning the screws, Sc, triangle TI can be brought into a horizontal plane parallel to the one defined by ring R, and can be raised or lowered to any desired level. It is thus easy to set triangles Tz and Ti just tangent at three points t o cap C and crucible G, respeotively, rendering the entire apparatus stable.
FIGURE 1. DIAGRAM OF APPARATUS P total len th 37 mm.; diameter 3.5 mm * beight of head 7 mm.; 3iaAeter of head 9 mm:; diamete; of groove, 3.5 Am * depth of groove, 2.5 ’mm. 81, tdth length, 35 mm.; external diameter, 6 mm.; internal diameter (exclusive of threaded portion) 3.75 mm.; height of head, 4 mm.; diameter of head, 9 dm.; height of auvporting nut N 5 mm.; diameter of nut, 9 mm. Sc, total length, 40’mm.; diameter (exclusive of grooved head), 3 mm.; height of knurled nut, 7 mm.; external diameter of nut, 9,mm.; internal diameter of nut, 7 mm.; depth of cylindrical cup In nut, 3 mm.
Triangles made of nichrome wire covered with fused-silica (“vitreosil”) tubes, the one measuring 3.8 cm. (1.5 inches) and the other 5.1 om. (2 inches) on a side, are well suited to a 20-ml. perforated platinum crucible of the usual form, and when properly adjusted stand about 15 mm. apart. The steel parts of the outfit have not as yet been observed to burn, even when the full power of the Tirrill burner, B, was being utilized. Rusting may be prevented by coating them with light machine oil when not in use.
Literature Cited (1) Gooch, F. A.,Proc. Am. Acad. Arts Sci., 13, 342 (1878); A m . Chem. J.,2, 250 (1880). RECEIVH~D November 10, 1936.
