was present in the neighbourhood of the sore. From this time it healed with great rapidity, although no special care was taken to protect it. Once healed, it never broke down again after the return of sensibility to painful cutaneous stimuli.
About this time, part of the first interosseous space, which had become sensitive to prick, began to respond to ice; this return of sensation was found to be associated with a few definite cold-spots. But the affected area still remained insensitive to heat.
On October 3 (161 days after the operation), we noticed, for the first time, that cotton wool produced some sensation over the upper patch on the forearm. This change advanced with considerable rapidity, and on October 6 sensibility to cotton wool was present in a very defective form over both upper and lower forearm patches. The upper of these areas seemed to become sensitive by gradual encroachment from the edges, whilst the lower appeared to recover at the centre as quickly as at the periphery. Later we found that this response was due entirely to the return to the hairs of a peculiar form of sensibility.
About this time (October 8), the upper patch on the forearm became undoubtedly sensitive to temperatures of and above 45° C. An excellent heat-spot was found in the centre of the patch, to which this return was certainly due.
By October 15 (173 days after the operation), no part of the hand was entirely insensitive to prick, although sensation was defective over the parts dotted on fig. 12.
The greater part of the back of the hand now reacted to the more extreme degrees of cold, and the cold-spots had multiplied greatly. By November 1 (190 days after the operation), cold could be appreciated everywhere over the back of the hand, and twenty-four cold-spots were discovered within the affected area. At the same time, one heat-spot was found near the base of the first phalanx of the thumb. This was the only part of the affected area on the hand sensitive to heat.
From this time, the cold-spots and heat-spots rapidly increased in number over the back of the hand, the increase proceeding step by step with the recovery of sensibility to cold and to heat.
With the gradual return of sensibility to pain, cold, and heat, we noticed that the sensation tended to be widely diffused, and was not infrequently localized in some part remote from the point of stimulation (September, 1903). If, for instance, ice was applied to the proximal portion of the forearm, a sensation of coldness was produced in the thumb. The site of this referred sensation remained the same, whatever
