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T H E J O U R N A L OF I N D U S T R I A L A N D ENGTNEERING C H E M I S T R Y
The readings may be made by using light directly transmitted or the comparator may be tilted by placing books under the end toward the observer and light may be reflected from a white surface through the tubes. It is possible by using this improved comparator t o examine, in a given time, many times the number of samples which could be examined by the old method.
SUBSTITUTES FOR PLATINUM WIRE IN BEAD AND FLAME TESTS By C. C. Kiplinger MT. UNION COLLEGE, ALLIANCE,OHIO Received January 2, 1920
One very important source of waste in platinum arises from its extensive use in the qualitative laboratory. The wire alloys with many of the metals with which i t comes in contact in the several tests, becomes brittle, breaks, and soon disappears. Under these conditions, the platinum is a total loss. To avoid this waste i t has been found feasible t o use a lead pencil “lead” in place of the wire for making bead tests. A piece of the “lead” 5 t o 6 cm. in length is held by tongs in the Bunsen flame until the end is red-hot, then dipped in borax and returned t o the flame, holding i t a t such an angle t h a t the borax glass forms a hanging drop on the end of the “lead.” This drop constitutes the bead and the tests are made as usual. Each length of “lead” serves for two tests a t least, one on each end. Often the graphite can be scraped clean enough t o permit of several tests with one piece. If not too large, the bead adheres firmly t o the graphite, yet the cold borax glass may be readily removed with a:knife. The reducing action of the carbon does not seem t o interfere materially.
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GENERAL SESSION HENRYW. RIEL,Mayor of St. Louis. Address of Welcome. W. A. NOYES,President, American Chemical Society. Response. PAULW. BROWN,Editor, America at Work. The Physical Basis for the Economic Development of the Mississippi Valley. CHAS.H. HERTY,Editor, Journal of Industrial and Engineering Chemistry. Victory and Its Responsibilities. AMOSA. FRIES,Director, Chemical Warfare Service, Chemical Warfare. J. H. HILDEBRAND.The Prediction of Solubility. VICTORLENHER. Selenium Oxychloride, a Neglected Inorganic Solvent. E. T.WHERRY. Studying Plant Distribution with Hydrogen Ion Indicators. G. H. A. CLOWES. Adsorption of Alkaloids. 0. H . PIERCE. The Chemical Resources of the St. Louis District. AGRICULTURAL AND FOOD CHEMISTRY DIVISION
C. E. COATES,Chairman T. J. BRYAN,Secretavy 1. C. E. COATES. Louisiana Molasses and Sirup. 2. GEORGEDEFREN. The Use of Refined Edible Lactic Acid in Food Products. 3. H. S. GRINDLEY.Preliminary Feeding Experiments with Pigs to Determine the Nutritive Value of the Amino Acids of the Proteins of Feedingstuffs. (Lantern.) 4 C. T. DOWELI,. Proteins of Pecans. 5. FREDH. SMITH.Body Fat of Hogs Fed on Peanuts. 6. J. W. REED. An Accurate and Rapid Dry Combustion Method for the Simultaneous Determination of Soil Organic Matter and Organic Carbon.
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No. 5
I n a method described b y Ehringhaus,l a small strip of filter paper is wet with the solution t o t o be tested and held in the flame, or one end of the paper is placed in the solution and the other end in the flame. The writer has found the latter method very convenient if used in conjunction with the following device: A glass tube 1 5 cm. long and 6 mm. in internal diameter is bent a t a n angle of 45’ 2 cm. from one end, and t h e latter is held in the flame until the opening is reduced t o a diameter of 3 mm. t o 4 mm. A strip of filter paper 4 cm. long is rolled t o fit tightly the reduced opening and forced into the tube, leaving about 3 cm. projecting. The longer arm of the tube is filled with the solution t o be tested, or with dilute hydrochloric acid, if a powder is t o be tested on the paper, and the paper wick is inserted in the flame, holding the tube a t such an angle t h a t i t feeds properly. A flame of 3 or 4 min. duration can easily be obtained. The burning carbon tends, however, t o mask the color of the substances looked for. While this is of no consequence in spectroscopic tests, i t is of vital importance in direct vision work. It is possible t o eliminate the carbon flame partly by supporting a burner horizontally on a stand, and bringing the upper edge of t h e paper wick barely within t h e bottom portion of the flame. The salt solution is vaporized and colors the flame with a minimum consumption of paper. A clean iron nail not less t h a n 3 mm. in diameter will be found t o be of value in these tests. Owing t o the relatively large surface offered by the head of t h e nail, the latter seems peculiarly adapted for this purpose. The nail can be easily cleaned and burned free from sodium, and in general the spectra of the iron salts do not interfere. 1
Chem. Abs., 18 (1919), 3115.
SCIENTIFIC SOCIFTIES FIFTY-NINTH MEETING AMERICAN CHEMICAL SOCIETY, ST. LOUIS, MO., APRIL 1 2 TO 16, 1920 PROGRAM OF PAPERS
Vol.
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7. J. W. REEDAND R . H. RIDGELI,. The Actual Carbon Content of Soil Organic Matter and Its Relation to the Use of Conventional Factor. 8. W. D. RICHARDSON.Limitations of the White Rat as an Experimental Animal. 9. W. D. RICHARDSON. Mammalian os Avian Dietary Experiments. 10. HERBERTBAILEY AND W. D. BALDSIEFEN.The Ether Insoluble Hexabromides of Pure and Adulterated Linseed Oils. 11. J. S. HUGHESAND E. F FERRIN. The Relative Nutritive Value of Alfalfa as a Supplement to a Diet of Corn and Tankage and Ka6ir and Tankage. 12. JAY BARTON. Data on Bacterial Count of Beverages in Missouri. 13. C. 0. SWANSON. Hydrocyanic Acid Present in Sudan Grass. AND W. L. LATSNAW. Effect of Alfalfa on the Sulfur 14. C. 0. SWANSON of the Soil in Comparison with Grain Crops. 15. L H. ALMYAND E FIELD, The Preservation of Fish Frozen in Chilled Brine. I-The Penetration of Salt. BIOLOGICAL CEEMISTBY DIVIBION R A. GORTNER, Chairman A. W. Dox, Secretary 1. C. 0. JOHNSAND H. C. WATERMAN.Some Proteins from the Georgia
Velvet Bean, Stieolobium Deeringianum. (Lantern.) 2. C. 0. JOHNSAND A. J. FINKS. The Deficiency of Cystine in Proteins of the Genus Phaseolus. (Lantern.) 3. P. A. KOBER. Studies on Neoarsphenamines. AND GEORGE E. HOLM. O n the Colorimetric Estima4. R. A. GORTNER tion of Tyrosin by Folin’s Phenol Reagent. 5. GEORGEE. HOLMAND R A. GORTNER.O n the Origin of the Humin Formed by the Acid Hydrolysis of Protein. VI-The Effect of Acid Hydrolysis upon Tryptophane. 6. M. X. SULLIVAN AND R. E. STANTON. The Alkali Reserve in Pellagra. 7. S. I,. JODIDI,S. C MOULTON AND K.S. MARKLEY.The Mosaic Disease of Spinach as Characterized by its Nitrogen Constituents.
