This report describes an investigation of vitamin C in various varieties of apples and the effects of maturity, soil, age of tree, storage and temperature on the vitamin content. The results are reported of experiments for the detection of any possible correlation between the antiscorbutic potency and the physiologic condition of the plant, maturity of the fruit, soil, age, storage and effect of heat. The experiments are based on the assumption that the vitamin C content of fruit is determined by a number of physiologic factors the revealing of which may disclose information on the nature and identity of the vitamin. Previous investigations have shown that the apple is a poor source of vitamin C. The process of canning or desiccation largely inactivates the vitamin. Apples gradually lose their potency during storage. Apples immersed in 2 per cent salt solution for eighteen hours before processing, however, retain their natural potency.