Numerous other investigators have reported figures of this character. Thus, Nichols and Bailey give the following as averages of the lower thresholds in the case of measurements on forty-six women: Sugar 1 part to 204 parts water Salt 1 part to 2,000 parts water Acid 1 part to 3,300 parts water Bitter 1 part to 456,000 parts water It is neither profitable nor interesting to draw close comparisons between the various sets of measures, since they vary considerably with the substance used, and since, after all, as one writer remarks, “the experiments are chiefly valuable as gratifying our curiosity.” Various students of individual differences have sought to determine the presence of sex differences, age differences, race and group differences, in these minimal taste stimuli. But the incidental factors are so numerous and so beyond experimental control that, if such differences exist, it has never been possible consistently to demonstrate their nature or amount. _Relative Sensitivity of Taste and Smell_ A recent investigation by Parker and Stabler was directed toward a question which possesses a certain interest. Reasoning that, since taste and smell are both “chemical” senses, it might be possible to compare their respective sensitivities in terms of the strength of solution required to affect them both, they attempted to make such comparison in the case of one substance. Pure ethyl alcohol is a substance which has both a distinctive taste and a distinctive odor. These investigators found that the minimum amount of this substance that could be sensed by taste was 24,000 times as great as the least amount that could be detected by odor. _The Discrimination of Tastes_