WE have read with much interest the communication from Dr. K. Kekcheev in NATURE of October 24. Just before the War, in an attempt to measure quantitatively the organoleptic properties of cheese, we were engaged in some experiments on the effect of olfactory stimuli on thresholds for monochromatic light for the dark-adapted eye. We appeared to get both increases and decreases in threshold with certain subjects and stimuli, and as soon as we became aware of Kravkov's work we planned to continue and extend our experiments. At our suggestion the late Mr. F. J. Dix constructed an apparatus in which the stimuli could be carefully controlled and, following the results of Schiller1 and Kravkov2, ensuring that the subject was isolated from noise. Mr. Dix began to accumulate data which substantiated our earlier findings as well as those of Kravkov for olfactory stimuli, but his untimely death, as well as the need for concentrating all our efforts on work which seemed to be of more immediate importance in our industry, has precluded the continuation of the investigation since then.