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A Human Experiment in Nerve Division
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the place he supposed had been touched. Lastly, R. touched the affected area at a spot he had marked on a life-sized photograph of the left hand, whilst H. attempted to mark the spot on a similar photograph. This is the method of Victor Henri [19], and in this case it gave surprisingly good results.

A fortnight after the operation, on May 9, it was found that of twenty-nine touches within the affected area, seventeen were quickly appreciated and accurately localized, six were not localized correctly, and six were not appreciated at all. It must be remembered, that at this stage the skin over the affected area was swollen, which somewhat hindered these experiments. The passing away of the swelling rendered the later experiments even more striking.

On May 17 a series of twenty-four observations was recorded by Henri's method on life-sized photographs. The results were remarkable, and it could not be said that there was any difference between the two hands in the quickness and accuracy with which pressure, touches were localized.

R. chose nine spots in various parts of the affected area unknown to H.; these are marked in black on the annexed figures (figs. 15 and 16). The following table gives the places stimulated in order and the position of the spots marked by H. on his photograph:—

(2) Localized exactly.

(3) Localized 1·3 cm. from the spot touched.

(4) Localized exactly.

(8) Lay over the interphalangeal joint of the thumb, and was localized near the metacarpo-phalangeal joint at a distance of 2·5 cm.

(1) Localized exactly.

(9) Over metacarpal of thumb—localized at a spot 2·5 cm. distant in interosseous space.

(6) Localized 0·5 cm. from spot touched.

(5) Localized 0·75 cm. from the spot touched.

(7) Localized 1·0 cm. on the proximal side of the point touched.

(2) Localized exactly.

(4) Localized exactly, so much so that the mark of the previous record was identical with that of this stimulation.

(7) Localized 1·0 cm. from point touched over the same spot as before.

(6) Localized exactly.

(8) Localized exactly.

(9) Localized 3 cm. distal to the spot stimulated.