rt, but it is equally a fact that
the fancied resemblance becomes less apparent as soon as the writing is
examined by a capable and painstaking expert. It should not be forgotten
that it is not every person who undertakes the comparison of
handwritings who is qualified for the task, any more than every doctor
who diagnoses a case can be depended upon to arrive at an accurate
conclusion. But if the tried and accepted principles of the art be acted
upon, there should be no possibility of error, always assuming that the
person undertaking the examination has a sufficiency of material for
comparison. An expert who valued his reputation would, for example, be
very cautious about giving an emphatic opinion if the only material at
his disposal were two or three words or letters. It is quite possible
that a clever mimic might reproduce the voice of another person so
accurately as to deceive those who knew the subject of the imitation;
but let him carry on a conversation in the assumed voice for a few
minutes, and detection is certain. In like manner, while a few
characters and tricks of style in writing may be fairly well imitated,
it is impossible to carry the deception over a number of words. Sooner
or later the forger lapses into some trick of his own, and it is here
the trained observer catches him. The expert, like the caricaturist,
lays himself out to note the peculiarities of his subject, knowing that
these are practically beyond the control of the writer, and that the
probabilities are that he is not even aware of them. Peculiarities in
handwriting, like unchecked habits in children, become, in time,
crystallised into a mannerism so fixed as to be part of the nature, and
consequently are difficult of eradication. As a matter of fact a
peculiarity in handwriting is more often cultivated than controlled,
many writers regarding a departure from orthodox copybook form as an
evidence of an "educated hand."

_The Law of Probabilities._--In examining a writing for comparison with
another the expert notes all peculiarities, which he labels, for
distinctive reference, "tricks." When he has recorded as many as
possible he looks for them in the writing which he has to compare.
Suppose that he has taken note of a dozen tricks, and finds them all
repeated in the suspected writing. The law of probabilities points to a
common authorship for both writings, for it is asking too much to expect
one to believe that there should exist two d