others similar in character will have entered the school, so that the
teacher can never expect perfection in the operation of any of his
plans.

I found so much relief from the change which this plan introduced, that
I soon took measures for rendering it permanent; and though I am not
much in favor of efforts to bring all teachers and all schools to the
same plans, this principle of _whispering at limited and prescribed
times alone_ seems to me well suited to universal adoption.

The following simple apparatus has been used in several schools where
this principle has been adopted. A drawing and description of it is
inserted here, as by this means some teachers, who may like to try the
course here recommended, may be saved the time and trouble of contriving
something of the kind themselves.

The figure _a a a a_ on the next page is a board about 18 inches by 12,
to which the other parts of the apparatus are to be attached, and which
is to be secured to the wall at the height of about 8 feet, and _b c d
c_ is a plate of tin or brass, 8 inches by 12, of the form represented
in the drawing. At _c c_, the lower extremities of the parts at the
sides, the metal is bent round, so as to clasp a wire which runs from
_c_ to _c_, the ends of which wire are bent at right angles, and run
into the board. The plate will consequently turn on this axis as on a
hinge. At the top of the plate, _d_, a small projection of the tin turns
inward, and to this one end of the cord, _m m_, is attached. This cord
passes back from _d_ to a small pulley at the upper part of the board,
and at the lower end of it a tassel, loaded so as to be an exact
counterpoise to the card, is attached. By raising the tassel, the plate
will of course fall over forward till it is stopped by the part _b_