SPEECH in disseminated sclerosis has been described in so many conflicting and indefinite ways that an attempt at accurate fixation by graphic records and analyses of the curves seems desirable. The speech is recorded by the phonautograph method. The patient speaks into the mouthpiece of a wide rubber tube ( fig. 1 ). This leads to a metal tube covered by a flexible membrane ( fig. 2 ). The movements of the membrane are recorded by a lever writing on a moving blackened cylinder. A record of

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... sung by a normal voice is reproduced in fig. 3 . The waves begin faintly; they rise quickly to full intensity. They are quite regular. In the record of a vowel each wave represents one vibration of the glottis. The length of a wave records the duration of a vibration. Slow vibrations, which produce low tones, are recorded as long waves; fast vibrations, or high tones, as short waves. Since the speed of the recording drum is known, a measurement of the length of a wave will give the duration of the vibration and the pitch of the tone. For example, with a surface speed of 1 mm. equal to 0'0085 sec, a wave of 0'9 mm. is the record of a vibration whose duration was 00085 x 09 = 000765 sec. If one vibration occupied this time, then the frequency, or the number of vibrations per second, would be 1 + 0-00765 = 131.