SOC., xxiv., 580.)-In the method depending on the oxidation by permanganate of cuprous thiocyanate (Jourlz. Amer. Chem. SOC., xxii., 685) the end-reaction is sometimes unsatisfactory. This can be obviated by the following modification : The washed precipitate of cuprous thiocyanate and the asbestos pulp are returned to the original beaker, 10 C.C. of a 10 per cent. potassium hydroxide solution and 10 C.C. of ammonia (specific gravity, 0.96) are added, and potassium permanganate solution is

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... iately added until, upon warming to 50°, a green colour remains. About one-third or one-fourth of the quantity of permanganate necessary for this is then run in, and the whole allowed to stand for five minutes, acidified with 25 C.C. of sulphuric acid (1 : 1 or Z), and the titration finished as usual. The results obtained with this method are very good. To calculate results, the iron value of the permanganate is multiplied by the factor 0.1602. A New Qualitative Teat for Cobalt. J. L. Daneiger. (Journ. Arner. Chem. SOL, xxiv., 578.)-About 5 C.C. of the solution to be tested is acidified with hydrochloric acid, solid ammonium thioacetate added, followed by a few drops of stannous chloride, and an equal volume of amyl alcohol; mixtures of acetone and ether, or alcohol and ether, may also be used, though less efficiently. The whole is well shaken and allowed to stand. If cobalt is present the upper layer will be coloured an intense blue from the formation of the double salt (CH&OS),Co, SCH,COSNH,. The test is as sensitive as Vogel's (ANALYST, xxvi., 218), and will serve THE ANALYST. cone with the deposit was then washed with water and with alcohol, and ignited in a muffle for a few minutes to convert the hydroxides into vanadic anhydride (V,O,), allowed to cool slowly in a dry atmosphere, and weighed. The results thus obtained were within 0.0005 gramme of the theoretical amounts.