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 of the first metacarpal had become sensitive to prick. The analgesic area on the back of the hand was diminishing from its radial aspect. In spite of these changes, the borders for the loss of sensation to cotton wool remained exactly as before.

On the forearm, ice was not appreciated with certainty, until the original border of cutaneous analgesia was passed. Water above 50° C. produced pain within the parts now sensitive to a prick, but it was impossible to say whether the pain was accompanied by any thermal quality.

The terminal phalanx of the thumb was certainly sensitive to cold below 17° C. and more doubtfully to heat above 45° C. Within the area of dissociated sensibility in the first interosseous space, and over the ball of the thumb, it was difficult to be sure that any sensation of temperature was produced by ice-cold and hot water; but the border of the thermo-ansesthesia probably lay slightly within that for sensibility to cotton wool.

At this time, some of the hairs on the forearm within the affected area became sensitive to pulling. The sensation produced was slowly developed and excessively unpleasant. It died away, and recurred again, without further stimulation. Those hairs lay entirely within the upper antesthetic patch.

On August 10 (107 days after the operation), the sensibility to prick had further improved, although the extent of the anaesthesia to cotton wool remained entirely unaltered. On August 15, for the first time since the recovery of sensation began, it could be said that parts which were at first insensitive to heat and cold now responded definitely and constantly to these stimuli. Over the upper patch on the forearm, ice uniformly produced a sensation of cold. Temperatures above 50° C. caused a stinging sensation, usually called " burning," but it is doubtful to what extent this contained more than the painful element of heat.

The terminal phalanx of the thumb undoubtedly responded to temperatures above 45° C, and the sensation produced by temperatures above 50° C. contained a thermal element in addition to the stinging pain. Even the proximal phalanx of the thumb had become sensitive to ice, although still anassthetic to heat.

On August 15 and 16, these observations on the upper patch of the forearm and the terminal phalanx were confirmed, and within these areas we were able to mark out definite cold-spots for the first time since the operation. Four of these lay in the upper patch, and four over the terminal phalanx of the thumb.