, not more on one side of the mouth than on
the other. Even a very narrow porte, not a quarter the width of the
tongue, will suffice, when pressure is used, to defeat this defence, and
completely to engage the tongue within the porte. But being then much
compressed, it will sustain a great part of the leverage, and the horse
will endeavour still more to make his tongue the fulcrum of the bit,
and to relieve his bars from that office, by protruding his tongue, and
thus forcing the thick part of it within the porte. If the porte is made
wide so as to allow space for the tongue, the corners formed by the
porte and the cannons (those parts between the porte and the branches)
are apt to work injuriously against the bars, and also to slip quite off
them, which makes the action of such bits uncertain, though they are
very effective and severe if the mouthpiece is no wider than the horse's
mouth. But the mouthpiece which gives complete room for the tongue, and
yet brings the cannons into perfect contact with the bars, is that of
which M. de Solleysell claims the invention, and which he describes as
"a pas d'asne, with the porte gained from the thickness of the heels."
Let the mouthpiece be in width four inches inside, this I believe, will
be sufficient for most horses, since the part of a horse's mouth where
the bit should work is narrowest, and the cheeks should consequently be
set outward. Let the entrance to the porte, between the heels be
three-fourths of an inch, and let the porte open laterally to two and a
half inches inside.

[Sidenote: Defence by the lip.]

But when the tongue is perfectly disengaged from the bars by the porte,
the horse will still defend them by drawing his lip in on one side,
interposing it between one bar and one cannon of the bit, and pulling on
one side of his mouth only. It is the common error to attribute this to
nature having formed one bar stronger than the other; but these and
other tricks are not to be looked on as the results of natural defects,
but as habitual defences against the pain caused by a hard, harsh
bearing on the horse's bars; with a smooth and gentle bearing he will
not take to them, or will discontinue them. For callous bars Xenophon
prescribes gentle friction with oil! and the practice of the Augustan
age of the manege, recommended by Berenger was to amputate that part of
the tongue which a horse protruded or lolled out!

[Sidenote: Defence by the teeth.]

One of the most