122 FINGER PRINTS
CHAP.
Though the unanimity of the results is wonderful, they are fairly arrived at, and leave no doubt that the relationship of any one particular digit, whether thumb, fore, middle, ring or little finger, to any other particular digit, is the same, whether the two digits are on the same or on opposite hands. It would be a most interesting subject of statistical inquiry to ascertain whether the distribution of malformations, or of the various forms of skin disease among the digits, corroborates this unexpected and remarkable result. I am sorry to have no means of undertaking it, being assured on good authority that no adequate collection of the necessary data has yet been published.
It might be hastily inferred from the statistical identity of the connection between, say, the right thumb and each of the two fore-fingers, that the patterns on the two fore-fingers ought always to be alike, whether arch, loop, or whorl. If X, it may be said, is identical both with Y and with Z, then Y and Z must be identical with one another. But the statement of the problem is wrong ; X is not identical with Y and Z, but only bears an identical amount of statistical resemblance to each of them ; so this reasoning is inadmissible. The character of the pattern on any digit is determined by causes of whose precise nature we are ignorant ; but we may rest assured that they are numerous and variable, and that their variations are in large part independent of one another. We can in imagination divide there into groups, calling those that are common to the
