is master of this secret,
and has his clue to the labyrinth, he will never attain the end he
proposes; particularly in his first lessons, upon which the success of
the rest always depend. These principles being established we may reason
in consequence of them with clearness.

In horsemanship, the Body of man is divided into three parts; two of
which are moveable, the third immoveable.

The first of the two moveable parts is the Trunk or Body, down to the
Waist; the second is from the Knees to the Feet; so that the immoveable
part is between the waist and the knees. The parts then which ought to
be without motion are the Fork, or Twist of the horseman, and his
thighs; now that these parts should be kept without motion, they ought
to have a certain hold and center to rest upon, which no motion that the
horse can make can disturb or loosten; this point or center is the basis
of the hold which the horseman has upon his horse, and is what is called
the SEAT; now if the seat is nothing else but this point or center, it
must follow, that not only the true grace, but the symmetry and true
proportion of the whole attitude depend upon those parts of the body
that are immoveable.

Let the horseman then place himself at once, upon his Twist, sitting
exactly in the middle of the saddle; let him support this posture, in
which the Twist alone seems to sustain the weight of the whole body, by
moderately leaning upon his buttock.

Let the Thighs be turned inward, and rest flat upon the sides of the
saddle; and in order to this let the turn of the thighs proceed directly
from the hips, and let him employ no force or strength to keep himself
in the saddle, but trust entirely to the weight of his body and thighs;
this is the exact equilibrio: in this and this only consists the
firmness and support of the whole _building_; a firmness which young
beginners are never sensible of at first, but which is to be acquired,
and will always be attained by exercise and practise. I demand but a
moderate stress upon the buttocks, because a man that sits full upon
them can never turn his thighs flat to the saddle; the thighs should
always lay flat to the saddle, because, the fleshy part of them being
insensible, the horseman would not otherwise be able so nicely to feel
the motions of his horse: I insist that the turn of the Thigh must be
from the Hip, because it can never be natural, but as it proceeds from
the hollow of the hip bone.

I insist fa