eneral appearance and pictorial effect of the writing
will suggest, as the measure of resemblances or differences
predominates, an impression upon the mind of the examiner as to the
genuine or forged character of the signature in question. When it is
understood that to make a forgery available for the purposes of its
production it must resemble in general appearance the writing of the
person whose signature it purports to represent, it follows as a
reasonable conclusion that resemblances in general appearances alone
must be secondary factors in establishing the genuineness of a
signature by comparison--and the fact that two signatures look alike
is not always evidence that they were written by the same person.

As an illustration of the uncertainty of an impression produced by the
general appearances and close resemblance of signatures, even to an
expert observer, is manifested when the fac-simile signatures of the
signers of the Declaration of American Independence, as executed by
different engravers, are examined. On comparing each individual
fac-simile made by one engraver, with the fac-simile of the same
signature made by another engraver, they will be found to exactly
coincide in general appearance as to form and pictorial effect, and so
much so, that the fac-similes of the same signature made by different
engravers cannot be told one from the other. On examining them by the
use of the microscope they may be easily determined as the work of
different persons. While this is likewise true of the resemblances in
general appearance which a disputed signature may have when compared
with a genuine signature of the same person, it is also true that the
measure of difference occurring in the general appearance of a
disputed signature, when compared with genuine ones of the same
person, are not always evidence of forgery.

There are many conditions affecting the production of signatures,
habitually and uniformly apart from the causes which prevent a person
from writing signatures twice precisely alike, under the influence of
normal conditions of execution. The effect of fatigue, excitement,
haste, or the use of a different pen from that with which the
standards were written, are well known conditions operating to
materially affect the general appearance of the writing, and may have
been, in one form or another, an attendant cause when the questioned
signature was produced, and thus have given to the latter some
variation