“We have arrived at the point at which it will be plain that the condition produced in these cases, and known under a varied jargon invented either to conceal ignorance, to express hypotheses, or to mask the design of impressing the imagination and possibly prey upon the pockets of a credulous and wonder-loving public—such names as mesmeric condition, magnetic sleep, clairvoyance, electro-biology, animal magnetism, faith trance, and many other aliases—such a condition, I say, is always subjective. It is independent of passes or gestures; it has no relation to any fluid emanating from the operator; it has no relation to his will, or to any influence which he exercises upon inanimate objects; distance does not affect it, nor proximity, nor the intervention of any conductors or non-conductors, whether silk or glass or stone, or even a brick wall. We can transmit the order to sleep by telephone or by telegraph. We can practically get the same results while eliminating even the operator, if we can contrive to influence the imagination or to affect the physical condition of the subject by any one of a great number of contrivances. “What does all this mean? I will refer to one or two facts in relation to the structure and function of the brain, and show one or two simple experiments of very ancient parentage and date, which will, I think, help to an explanation. First, let us recall something of what we know of the anatomy and localization of function in the brain, and of the nature of ordinary sleep. The brain, as you know, is a complicated organ, made up internally of nerve masses, or ganglia, of which the central and underlying masses are connected with the automatic functions and involuntary actions of the body (such as the action of the heart, lungs, stomach, bowels, etc.), while the investing surface shows a system of complicated convolutions rich in gray matter, thickly sown with microscopic cells, in which the nerve ends terminate. At the base of the brain is a complete circle of arteries, from which spring great numbers of small arterial vessels, carrying a profuse blood supply throughout the whole mass, and capable of contraction in small tracts, so that small areas of the brain may, at any given moment, become bloodless, while other parts of the brain may simultaneously become highly congested. Now, if the brain or any part of it be deprived of the circulation of blood through it, or be rendered partially bloodless, or if it be excessively congested and overloaded with blood, or if it be subjected to local pressure, the part of the brain so acted upon ceases to be capable of exercising its functions. The regularity of the action of the brain and the sanity and completeness of the thought which is one of the functions of its activity depend upon the healthy regularity of the quantity of blood passing through all its parts, and upon the healthy quality of the blood so circulating. If we press upon the carotid arteries which pass