of the tongue, and all below it, are required. For one
sitting this single "pluck" will suffice, as it will serve for a
general examination. The lungs may be dilated by inserting a tube into
the windpipe, tying it in position, and blowing into it with greater
or less force. It should be especially observed how suddenly the lungs
collapse when the breath force is removed, as this illustrates well
their _elasticity_. By cutting through the windpipe lengthwise and
following it downward one learns how numerous are the branches of the
bronchial tree, etc.

For a second sitting one should secure at least two specimens of the
larynx of the pig or sheep, though the former is more like the human,
and so the better on the whole. A case of dissecting instruments is
not essential; a sharp pocket-knife will serve the purpose. In order
that the student may have a clear idea of the cartilages, all the soft
tissues must be cut or scraped away. It is necessary to exercise great
care, or the membranes connecting the cartilages together will be cut
through; and on the other hand, unless the work in the neighborhood of
the arytenoids be cautiously done, these cartilages may be injured,
and it is most important that their swivel-like action and their
relations to the true vocal bands be observed. The glottic chink can
be seen from above or below, and should be observed from both
view-points. Its margins are formed by the true vocal bands.

Then, with the figures before him, the student should endeavor to
isolate each of the muscles described. The muscles can always be
recognized by their red color, but it is to be remembered that those
on the inner surface of the larynx, such as the crico-arytenoid, are
covered with mucous membrane, which after death is very pale. This can
by careful dissection be removed, and if in doing this a small pair of
forceps be employed, the work will be greatly facilitated. One must be
very skilful indeed if he would get all the muscles "out," or well
exposed to view as individuals, on a single specimen. Likely several
will be required before entirely satisfactory results are reached, but
these are well worth all the time and labor required. The action of
the muscles can in some measure be demonstrated by pulling on them in
the direction of their loosest attachment, though it must be confessed
this is much more difficult in the case of most of the muscles of the
larynx than in those of other parts of the body.