curves and angles, proportion and relative position of the different
parts, and elaboration or extension of the extremities. In scarcely
one of these particulars can a man make two letters so much alike that
they cannot be distinguished by microscopical examination.

Although a great deal can be determined in a general way by close
observation with the naked eye, it is always best to employ some
magnifying power--usually an ordinary hand lens or pocket magnifier
will suffice--but the writer has found it better to use a microscope
objective of low power (four or five diameters), which is provided
with an easily slipping sleeve, terminating in a diaphragm which cuts
out the light entering the outside rim of the lens. This sleeve may be
pushed out for one or two centimeters, and the particular spot under
examination isolated from the adjacent parts without undue
magnification. It is one of the popular fallacies that a high
magnifying power is desirable in all cases of difficulty, but usually
the reverse is the case in questions of handwriting.

Experts have sometimes impressed the jury with the fact that they had
employed on some thick and opaque document, powers of several hundred
diameters without the lately applied illumination from the side,
reflected by a glass plate, introduced obliquely into the tube of
the microscope. Without such aid no microscopist need be told that
the light would be wanting to illuminate the field under these
circumstances. The best authorities prescribe a magnifying power of
not more than ten diameters for ordinary observation. For special
purposes higher powers are sometimes useful. An ocular examination of
the ink in the various parts of a written paper, document or
instrument of any kind will generally decide whether it is the same.