Classification and uses of finger prints / by Sir E.R. Henry.

  • Edward Henry
Date:
1913
Catalogue details

Licence: In copyright

Credit: Classification and uses of finger prints / by Sir E.R. Henry. Source: Wellcome Collection.

    59/168 page 49
    Accidentals (Figs. 33, 34, 35, 36 and Illustrations 125 to 132 inclusive). Fig. 33 might be described as an Arch with pocket. Fig. 34 at first sight, appears to be a Whorl surrounded by a Loop ; Illustration 127 to be a Whorl resting on a Loop ; 130 a Loop resting on a Whorl ; but more strict examination shows that such descriptions lack accuracy, and it is better therefore to group these varieties into subclass Accidentals of class Composites. Ridge Counting.—As about two impressions out of every three are Loops, the subdivision into ulnar and radial fails to split them up into groups sufficiently small, and it is necessary there- fore to still further differentiate them by other methods. Fig. 37 represents the ridges of an ordinary Loop. The line S B joins the two terminal points, “ inner ” and “ outer terminus.” If the ridges which cut the line S B are counted they will be found to number 17, so this Loop is specialised as a Loop with 17 ridges or counts, and if it is the impression of a right hand digit it would be further specialised as an idnar ; if of a left hand digit as a radial Loop. In ridge counting it must be remembered that the two terminal points are excluded from count, that ridges like G, which run close up to without meeting the line S B are also excluded, and that when two ridges result from a bifurcation as at D, close to the line S B, both are counted. A little practice will enable anyone with the help of a read-
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