1 The great advantage of the method is its extreme simplicity. From the beginning of an experiment until the end the contents of the crucible are not brought into contact with any foreign substance. By this means small errors resulting from incomplete precipitation, and filtration and all other errors incident to ordinary processes of analysis were avoided. 2 The nature of the metal and its oxide rendered them well adapted to weighing. The specific gravity of the metal and oxide approached so closely to that of the weights, that it was unnecessary to reduce the weighings to a vacuum standard. 3 The advantages derived from weighing by tares have been pointed out. 4 The closely agreeing results speak strongly in favor of the accuracy of the method. The Oxalate Method. The method consists in taking a weighed amount of cadmium oxalate, decomposing it by heat, when a mixture of oxide and metal are said to be formed, dissolving this mixture in nitric acid, converting the nitrate into oxide and weighing the oxide. Lenssen[8] obtained results by this method which agree very closely with those recorded in the earlier part of this dissertation. Working with the same method, Partridge[9] arrived at a value about one fourth of a unit lower than that of Lenssen. [8] Journ. f. prakt. Chem. 79, 281. [9] Amer. Journ. Science XL, 377. It appeared desirable that this method should be repeated with the greatest care to ascertain what result it would give under the most favorable conditions. Having a supply of pure cadmium it was necessary to prepare pure oxalic acid. Preparation of Pure Oxalic Acid. The commercial acid was crystallized three times from cold water to separate it from acid oxalates. It was then boiled for two days with a 15 per cent solution of hydrochloric acid, to remove any mineral matter present. The acid which crystallized from the hydrochloric acid solution was recrystallized twice from hot, redistilled alcohol and twice from pure ether. It was finally boiled with water to decompose any ethyl oxalate and twice crystallized from pure water. The acid was dried in the air at ordinary temperatures. This acid left no residue on ignition. Preparation of Cadmium Oxalate.