of the mind, as of hope or despondency. Or, more in detail, medical men have observed that certain mental states affect certain functions in certain definite ways. As, for instance, sudden anxiety, as of the non-arrival of a friend when expected, may cause an increase of the peristaltic action, while prolonged anxiety is apt to cause the contrary effect. Joy over good news or at the return of long-absent friends diminishes gastric secretion and causes loss of appetite. The feeble hold on life of the suicidal, and the surprising recoveries from serious diseases and after apparently fatal injuries, in persons whose mental characteristics are hopefulness and determination, are often-recurring facts, familiar to all.
The nature of what we call mind and its relation to the functions of the body is a very wide field of inquiry—too wide, indeed, for our present consideration. But having had unusually favorable opportunities for observing certain phases of psycho-biological relations, I ask your attention while I present some studies which may help us, possibly, to arrive at more practical results, through more satisfactory explanations of certain phenomena, than we have hitherto possessed. So, without further preface, I will introduce my subject by giving a striking example of the influence of a simple mental impression as distinguished from and as independent of thought, will, or consciousness in controlling the manifestation of function.
In September, 1876, I received a letter from a prominent physician living in a Western city, saying that he, in connection with two other medical men, had been treating, unsuccessfully, a case of ununited fracture of the left thigh-bone; and he inquired if I thought I could do or suggest anything which would lead to its union. The result of some correspondence was that, a few weeks afterward, in October, the patient presented himself with his father at my office.
The case was briefly as follows:
Two years before the young man had met with an accident, and had broken his thigh-bone just above the middle. The family doctor proceeded to set it and apply the proper dressings. In due course of time the fracture united, and the patient got about with some shortening of the limb, and walked with perfect facility for one year, when, in crossing the street, he fell and broke the same bone again about four inches, so they told me, below the seat of the former fracture. Neither of the physicians who had attended him on the previous occasion being in the city, a third medical man, a surgeon of national reputation, was called, who proceeded to apply the proper bandages for fracture. After that the three attended the case conjointly, but no union of the fracture could be obtained, they said, though every usual means had been exhausted to secure it. Such, in brief, was the case as it was presented to me. A careful examination revealed two facts. The first was that there was no ununited fracture, and the second was that the bone had not been broken at the second accident. He was a well-grown, finely formed,