v PATTERNS : THEIR OUTLINES AND CORES 7 5
(Plate 8, Fig. 14, 52), or they may run in broad curls of uniform width (Fig. 14, 51, 54). Perhaps the best general rule in selecting standard outlines, is to limit them to such as cannot be turned into any other by viewing them in an altered aspect, as upside down or from the back, or by magnifying or deforming them, whether it be through stretching, shrinking, or puckering any part of them. Subject to this general rule and to further and more particular descriptions, the sets (Plates 7 and 8, Figs. 11, 12, 13) will be found to give considerable help in naming the usual patterns.
It will be observed that they are grouped under the three principal heads of Arches, Loops, and Whorls, and that under each of these heads some analogous patterns as 4, 5,. 7, 8, etc., are introduced and underlined with the word " see " so and so, and thus noted as really belonging to one of the other heads. This is done to indicate the character of the transitional cases that unite respectively the Arches with the Loops, the Arches with the Whorls, and the Loops, with the Whorls. More will follow in respect to these. The " tented arch " (3) is extremely rare on the thumb ; I do not remember ever to have seen it there, consequently it did not appear in the plate of patterns in the Phil. Trans. which referred to thumbs. On the other hand, the " banded duplex spiral" (30) is common in the thumb, but rare elsewhere. There are some compound patterns, especially the " spiral in loop " (21) and the " circlet in loop" (22), which are as much loops as whorls ; but are reckoned as whorls.
