In the physiological study of speech articulations our most objective information has come, until recently, from radiograms. Now we have, in addition, spectrograms, which, if we learn to interpret them, can also give us very objective information. For the typical phase (portion) of a speech sound, the interest of a spectrogram may be about equal to that of a radiogram; but for the transitional phases, the interest of a spectrogram will probably be much superior; and from the practical viewpoint of availability, the spectrogram will have a marked advantage for it can be had in a few minutes and at low cost. But to the linguist, the usefulness of a spectrogram depends on his ability to interpret it in articulatory terms. We need not stress, therefore, the importance of investigating the relation between formant positions and speech organ positions at this stage of the still young science of sound spectrography.