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630, which is always stimulated painfully under the methods adopted by the experimenters.

6. Finally we have the argument from the important experiments made by Goldscheider, in which it is claimed that he has isolated pain nerves and terminals. This argument rests thus far upon the observation of one man; and in no field of science is it more likely than in that of neural anatomy that subsequent observers will find ground for modification of a first investigator's results. Goldscheider's early experiments led him to the important discovery of pressure spots, cold spots, heat spots, in the skin surfaces, but did not lead him to believe that his observations told of pain spots; later, led doubtless by his interest in the theory of specific energies, he came to the conclusion that the evidence did speak in favor of pain spots also. The article declaring for this latter position was published in 1885. Since then he has made many investigations, but principally in relation to the pressure, heat, and cold spots. His words have often implicitly denied the theory of specific pain nerves; but this may be passed over. In the same year, 1885, Blix published in the Zeitschrift für Biologie a series of observations and a discussion covering the same general ground, and his conclusion is that "there are three specific kinds of nerve apparatus in the skin, one for heat, one for cold, and one for pressure. For the sense of pain there are no specific organs proven in the skin" (Vol. XXI. p. 160). It appears to me that there is little ground to hold that Goldscheider's results are to be taken as conclusive. Wundt, in rewriting his Physiologische Psychologie for the third edition, has recognized Goldscheider's discoveries in relation to the heat, cold, and pressure spots, but he does not agree that he has proven his case with reference to pain. Professor Ladd, in his late Elements of Physiological