1.The "dead-stop" method of Foulk and Bawden has been found very convenient for the determination of the end-point in the precipitation ti七rations with ferrocyanide, if an applied voltage of about 50 millivolts is used.In 1M hydrochloric acid solution, zinc can be precipitated quantitatively by ferrocyanide as Zn₃K₂[Fe(CN)₆]₂, while cadmium remains in solution.After adding solid ammonium sulfate(about 9 grams in 60 ml.of solution)cadmium can be quantitatively precipitated as Cd₅(NH₄)₆[Fe(CN)₆]₄.