And, in later years, I have had colleagues with whom it was positively painful to walk down a crowded street, from the gruesome habit that they had of picking out, and condemning to lingering deaths, the cases of cancer, of Bright's disease, or of locomotor ataxia, that we happened to meet. Of course, they would be the first to admit that this was only what they would term a "long shot," a guess; but it was a guess based upon significant changes in the patient's countenance or gait, which their trained eye picked out at once, and it was surprising how often this snapshot diagnosis turned out to be correct.

The first thing that a medical student has to learn is that appearances are not deceptive—except to fools. Every line of the human figure, every proportion of a limb, every detail of size, shape, or relation in an organ, means something. Not a line upon any bone in the skeleton which was not made by the hand-grip or thumbprint of some muscle, tendon, or ligament; no bump or knuckle which is not a lever or hand-hold for the grip of some muscle; not a line or a curve or an opening in that Chinese puzzle, the skull, which was not made to protect the brain, to accommodate an eye, to transmit a blood-vessel, or to allow the escape of a nerve. Every minutest detail of structure means something to the man who will take the pains to puzzle it out. And if this is true of the foundation structure of the body, is it to be expected that the law ceases to run upon the surface?

Not a line, not a tint, not a hollow of that living picture, the face, but means something, if we will take the time and labor to interpret it. Even coming events cast their shadows before upon that most exquisitely responsive surface—half mirror, half sensitive plate—the human countenance. The place where the moving finger of disease writes its clearest and most unmistakable message is the one to which we must naturally turn, the face; not merely for the infantile tenth part of a reason which we often hear alleged, that it is the only part of the body, except the hand, which is habitually exposed, and hence open to observation, but because here are grouped the indicators and registers of almost every important organ and system in the body.

What, of course, originally made the face the face, and, for the matter of that, the head the head, was the intake opening of the food-canal, the mouth. Around this necessarily grouped themselves the outlook departments, the special senses, the nose, the eyes, and ears; while later, by an exceedingly clumsy device of nature, part of the mouth was split off for the intake of a new ventilating system. So that when we glance at the face we are looking first at the automatically controlled intake openings of the two most important systems in the body, the alimentary and the respiratory, whose muscles contract and relax, ripple in comfort or knot in agony, in response to every important change that takes place throughout the entire extent of both.

Second, at the apertures of the two most important members of the outlook corps, the senses of sight and of smell. These are not only sharply alert to every external indication of danger, but by a curious reversal, which we will consider more carefully later, reflect signals of distress or discomfort from within. Last, but not least, the translucent tissues, the semi-transparent skin, barely veiling the pulsating mesh of myriad blood-vessels, is a superb color index, painting in vivid tints—"yellow, and ashy pale, and hectic red"—the living, ever changing, moving picture of the vigor of the life-centre, the blood-pump, and the richness of its crimson stream. Small wonder that the shrewd advice of a veteran physician to the medical student should be: "The first step in the examination is to look at your patient; the second is to look again, and the third to take another look at him; and keep on looking all through the examination."

It is no uncommon thing for an expert diagnostician deliberately to lead the patient into conversation upon some utterly irrelevant subjects, like the weather, the crops, or the incidents of his journey to the city, simply for the purpose of taking his mind off himself, putting him at his ease, and meanwhile quietly deciphering the unmistakable cuneiform inscription, often twice palimpsest, written by the finger of disease upon his face. It takes time and infinite pains. In no other realm does genius come nearer to Buffon's famous description, "the capacity for taking pains," but it is well worth the while. And with all our boasted and really marvelous progress in precise knowledge of disease, accomplished through the microscope in the laboratory, it remains a fact of experience that so careful and so trustworthy is this face-picture when analyzed, that our best and most depended upon impressions as to the actual condition of patients, are still obtained from this source. Many and many a time have I heard the expression from a grizzled consultant in a desperate case, "Well, the last blood-count was better," or, "The fever is lower," or, "There is less albumen,—but I don't like the look of him a bit"; and within twenty-four hours you might be called in haste to find your patient down with a hemorrhage, or in a fatal chill, or sinking into the last coma.

It would really be difficult to say just what that careful and loving student of the genus humanum known as a doctor looks at first in the face of a patient. Indeed, he could probably hardly tell you himself, and after he has spent fifteen or twenty years at it, it has become such a second nature, such a matter of instinct with him, that he will often put together all the signs at once, note their relations, and come to a conclusion almost in the "stroke of an eye," as if by instinct, just as a weather-wise old salt will tell you by a single glance at the sky when and from what quarter a storm is coming.

I shall never forget the remark of my greatest and most revered teacher, when he called me into his consultation-room to show me a case of typical locomotor ataxia, gave me a brief but significant history, put the patient through his paces, and asked for a diagnosis. I hesitated, blundered through a number of further unnecessary questions, and finally stumbled upon it. After the patient had left the room, I, feeling rather proud of myself, expected his commendation, but I didn't get it. "My boy," he said, "you are not up to the mark yet. You should be able to recognize a disease like that just as you know the face of an acquaintance on the street." A positive and full-blown diagnosis of this sort can, of course, only be made in two or three cases out of ten. But the method is both logical and scientific, and will give information of priceless value in ninety-nine cases out of a hundred.

Probably the first, if not the most important, character that catches the physician's eye when it first falls upon a patient is his expression. This, of course, is a complex of a number of different markings, but chiefly determined by certain lines and alterations of position of the skin of the face, which give to it, as we frequently hear it expressed, an air of cheerfulness or depression, comfort or discomfort, hope or despair. These lines, whether temporary or permanent, are made by the contractions of certain muscles passing from one part of the skin to another or from the underlying bones to the skin. These are known in our anatomical textbooks by the natural but absurd name of "muscles of expression."

Their play, it is true, does make up about two-thirds of the wonderful shifting of relations, which makes the human countenance the most expressive thing in the world; but their original business is something totally different. Primarily considered, they are solely for the purpose of opening or closing, contracting or expanding, the different orifices which, as we have seen, appear upon the surface of the face. This naturally throws them into three great groups: those about and controlling the orifice of the alimentary canal, the mouth; those surrounding the joint openings of the air-tube and organ of smell, and those surrounding the eyes.