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operation, was not the equivalent of the normal sensation of light touch over hairless parts, but was a peculiar form of hair-sensibility. For the areas endowed with it remained anaesthetic to the painless interrupted current and to No. 5 of von Frey's hairs; moreover, the sensation produced was widely diffused and was referred to remote parts, exactly like the sensation of prick and ice-cold over the same regions. This hypothesis was found at a later date to be correct. For on shaving the areas endowed with this form of sensibility, they became entirely insensitive to cotton wool.

Fig. 13: November 12, 1904 (567 days after the operation). To show the manner in which sensibility returned to cutaneous tactile stimuli. The dotted area corresponds to the parts sensitive after shaving to cotton wool and to von Frey's tactile hairs (No. 5). These parts were also sensitive to temperatures of about 36° C.

We could not be certain that the forearm was sensitive to cotton wool when carefully shaved, until April 24, 1904, exactly a year after the operation.

On June 5, 1904 (407 days after the operation), the affected area on the forearm responded to temperatures of 37° C. This sensibility to warmth rapidly increased, and on June 26 was obtained, even with 34° C. Moreover, the sensation produced was one of warmth localized in the part touched. Except that it was not quite so acute, it exactly