The American journal of the medical sciences (1827)
[Thorofare, N.J., etc.] Charles B. Slack [etc.] · leaf 118
ngue-depressor, which adapts it to different patients, and has two stout ratchets, kept in position either with a spiral spring or slightly curved piece of steel, which presses on the upper end of the ratchet. It is necessary to wrap a piece of yarn around the part of the wire which presses on the… … Geo T I EM AN N8\ Co of the firm of Tiemann & Co., rendered me valuable aid in making this improvement, which consists in having the tongue-depressor attached by a double hinge-joint, and provided with a strong and flat steel spring; which at one end has teeth that catch against corresponding teeth…
Medicine
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