Abstracts -
APPARATUS, LABORATORY PRACTICE, AND DEMONSTRATIONS Apparatus for the Determination of Residues from Extractions, Chon.-Zlg.,54, 881 (November 12, 19311). -The extraction apparatus shown in the figure consists of a round-bottomed flask e, a connection tube b , with the removable extraction vrssel d, and the condenser c. The extraction vessel has the shape of a round-bottomed weighingbottle. Itisfittedwithasiphon andis supported by three legs made from glass. To determine the residue left after an extraction, placeanextraction thimblein the extraction vessel and dry both to constant weight. Weigh 1-2 grams of the substance to be extracted into the vessel and set up the apparatus in the usual manner. I t is advisable to keep the thimble twothirds filled with the solvent during the extraction. Aftenvard dry the vessel and determine the residue by weighing. The apparatus is manufactured by Rrchard
FORNAMEX.Chem.-Zlg., 54, 908 n and b and a stopcock b a t its The upper part is enlarged t o a cylinder c
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.L.. furic acid of definite specific gravity (2O0C.) by means of a long funnel the tip of which reaches to that mark o. The bulb b is filled with 25 cc. of benzine t o the zcro mark by means of a shorter funnel. The sulfonation is hastened by shaking. The excessinternal pressure caused by the heat produced during the reaction can be taken care of by manipulating the stopper. At the end of the sulfonation the buret is alloaed t o cool to 20°C. The sulfuric a d d is drawn offdown to the proper mark and the amount of residual benzine is read offon the buret. This buret is patented and manufactured by L. S. Aloij Krcidi. Prag. I, Husova 7. A New Pipet Viscometer. J. RoMNEY. Chem. b ind., 49, 986-8 (Nov. 21, I930).-This new instrument is designed for the rapid determination of the viscosity of E. R. W. lubricating oils. The Carbazole Reaction for Carbohydrates and Related Compounds. See this title, p. 575. A Note on the Purification of Mercury. A. 0. JONES. Chem. & I d . , 49, 437T4381. (Nov. 7, 1930).-Descriptions and illustrations of two forms of apparatus deE. R. W. signed to purify mercury by aerial oxidation and acid treatment. The Technic of Extracting Liquids Which Form Emulsions. W. WEINBERGER. Am. J. Pharm., 102, 5 9 6 5 (October, 1930).-Sometimes on extracting material wjth immiscible solvents (e. g., extracting organic matter out of any aqueous layer w t h ether) the liquid emulsifies when shaken and does not separate again mto two layers. This article tells how t o deal with such emulsions. Briefly summarized, they are: (1) Addition of an excess of the dispersed phare. (2) Addition of a solvent common to both phases. (3) Destruction of the emulsifying agent. (If soap, add acid; if albumen, formaldehyde). (4) Salting out. (5) Filtration. (6) Heating, freezing. and electrolyzing. (7) Centrifuging. G. 0.
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The Detection of Cobalt a s Cesium Cobaltiitrites. 11 Y n w n AS" ~ 11. hl PARTI . . I n > (,'lwni. .i,~., 52, 4857-8 10.
