Unfortunately, the Leica's take-up spool needs a long tapering tongue of film, which users must wedge under a spring clip on the spool's barrel before manually wrapping a few turns of film around it.

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It is available in capsules and tablets, as well as bedtime teas and a tincture, a liquid you can put under your tongue or mix with water.

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One is by contacting the body, like by a tip of an oral thermometer touching under the tongue.

FORBES: Body temperature.