of them have admitted, however, the nature of the leading principles'
which guide them. The philosophy of the matter rests mainly on the
fact that it is very rare for any two persons to write hands similar
enough to deceive a careful observer, unless one is imitating the
other. "Fists," like faces, have all some special idiosyncrasy, and
the imitator has not merely to copy that of some one else but to
disguise his own.

By careful and frequent practice he may succeed well enough to deceive
the ordinary man, but is rarely successful in baffling the expert.
Even the most skilful culprit cannot wholly hide his individuality, as
he is sure to relapse into his ordinary method occasionally. Then
again, great care has to be used, and this can be detected by the
traces of hesitancy, the substitution of curves for angles and _vice
versa_, which come out very plainly when the writing is examined under
the microscope, as it usually is by the expert.

A plan of detection which has been adopted with great success is to
cut out each letter in a doubtful piece of writing, and paste all the
A's, B's, etc., on separate sheets of paper. The process is also gone
through with a genuine bit of caligraphy of the imitator or the
imitated, as the case may be. Comparison almost invariably shows that
the letters are less uniform if imitation has been attempted, the
writer being occasionally betrayed into some approach to his ordinary
caligraphy, or into momentary forgetfulness of some special point in
the handwriting he is simulating.

No point is too small to escape an expert's attention. The dotting of
the "i's," the crossing of "t's," the curls and flourishes, the
intervals between the words, the thinness of the up-stroke and the