Page:Popular Science Monthly Volume 63.djvu/410

406 the arrangement of the formulæ, but simply completing the description.

Should a third classification be necessary, the presence, position or absence of the carpal triradius would furnish one, and for a fourth subdivision a counting of certain of the ridges, like those between the digital triradii as Galton does in his finger-tip system, might be suggested. In the last instance, where the decision of a definite case rests upon the identity of a certain individual, actual prints taken from his palms should be compared with the set in the collection which most closely corresponds in the formulæ to them, and the decision should be reached by the study of the minutæ, although there could hardly he a mathematical chance of a comparison going as far as that unless it was a case of actual identity.

 showing various relations of digital and main lines, (a) Lines A, B and C are open; line C is recurved and opens at 9; the third digital line is recurved around a pattern: the first and second digital areas are confluent; there is a single lower triradius [Collection No. 156]. (b) Lines A and B are open; line C is recurved; line D terminates in a lower triradius (the third?); the digital lines are all normal and the digital triradii are distinct; there are two lower triradii [Collection No. 86]. (c) Lines A, C and D are open; line B is recurved around a pattern and fuses with one of its own digital lines; the digital lines are in general much modified and the digital areas are all confluent; there is but one lower triradius, the first [Collection No. 59].

The previous pages have treated of the hands alone as though they were the only possibility of the system, but the soles of the feet exhibit fully as great a diversity in the course of their ridges, and their use in addition to that of the hands would furnish so complete a means of subdividing a collection of prints that the secondary classification, i. e., that which concerns the patterns and the carpal area, would hardly be necessary except to complete a description. The feet as well as the hands possess four main lines originating from the digital triradii, and as their formulæ are nearly as variant as are the others, the subdivisions rendered possible by the use of all four members are well-nigh infinite in number (see Figs. 5 and 6).