I have said that the knowledge of the ‘natural’ bone-setter must be both limited and inaccurate. Hence, though in those cases, in which the dislocation or fracture is so plain as to be readily seen, he may perhaps get along without any serious difficulty, he is exceedingly liable to make mistakes in cases which require nice discrimination. His mistakes may be arranged chiefly under four classes, which I will notice separately. First. A common error is supposing a fracture to be a dislocation. Generally there is no difficulty in deciding which of these accidents has taken place. In cases of fracture a crepitus (or grating of the broken ends of the bone upon each other) can be perceived on moving the limb in different directions. But sometimes it is difficult to perceive this, and it can only be done by executing some particular motions. In such cases the uneducated bone-setter is very liable to make a mistake and often does. I will relate but three out of many examples of this error which I have in my possession. The first case I take from Ticknor’s Medical Philosophy. A young lad in the city of New York received an injury of the elbow joint, which, under the most judicious surgical treatment, terminated in permanent stiffness. The parents of the lad took him soon after to a bone-setter who had acquired considerable celebrity. He at once pronounced the elbow to be out of joint, and attempted to set it. After repeated attempts, he at length by an extreme degree of violence, which was attended with excruciating pain, succeeded in straightening the limb. The bone-setter triumphed in the achievement, and the parents were delighted with the result. But the force employed to reduce the pretended dislocation did such violence to tendons, ligaments, and nerves, that the child’s life was in jeopardy, and was saved only by the timely amputation of the arm.