The ridges are studded with the openings of the sweat glands, the
elevated position of which is supposed to prevent them from being
clogged up; further, the moisture which they secrete perhaps adds to the
friction of the skin. Friction-skin patterns are inherited in some
degree. Photograph by John Howard Payne.]
[Illustration: THE LIMITS OF HEREDITARY CONTROL
FIG. 22.--Print of a finger-tip showing a loop-pattern,
enlarged about eight times. This is a common type of pattern, and at
first glance the reader may think it could be mistaken for one of his
own. There are, however, at least sixty-five "ridge characteristics" on
the above print, which an expert would recognize and would use for the
purpose of identification. If it were found that the first two or three
of them noted corresponded to similar characteristics on another print,
the expert would have no doubt that the two prints were made by the same
finger. In police bureaus, finger-prints are filed for reference with a
classification based on the type of pattern, number of ridges between
two given points, etc.; and a simple formula results which makes it easy
to find all prints which bear a general resemblance to each other. The
exact identity or lack of it is then determined by a comparison of such
_minutiae_ as the sixty-five above enumerated.
Pages:
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189