Mania is sometimes said to break out suddenly. As a matter of fact there are always preliminary symptoms; though these are of such a general nature that they may have escaped observation. The patient's history generally shows that there has been loss of appetite and consequent loss in weight, commonly accompanied by constipation and headache with increasing inability to sleep. Usually these symptoms have been present at least for some weeks or a month or more. Then the patient brightens up. Instead of the brooding so common before, there is a tendency to talkativeness; the eye is bright; the expression lively; in the midst of his loquacity the patient becomes facetious and jocular. The backward before become enterprising. Undertakings are attempted that are evidently far beyond the power, pecuniary or mental, of the individual. Active employment is sought, and, where this fails, restless to and fro movement becomes the habit. Friends notice this change in disposition, and also note a certain lack of connection in the ideas. There is apt to be a distinct change of disposition. A man who has been very loath to make friends before, now becomes easy in his manner toward strangers and takes many people into his confidence. In the severer forms motion becomes constant; the arms are thrown around; to and fro movement at least is kept up; the voice becomes loud and is constantly used. Patients can not be kept quiet, and, as a consequence of their constant movement, their temperature rises and loss of sleep makes them weaker and weaker until perhaps physical exhaustion ensues. {224} The causes of mania are not always so distinctly traceable as those of melancholia. Heredity is an important factor. This is, however, not so much a question of actual direct inheritance of mental disturbance from the preceding generation, as a family trait of mental weakness that can be traced through many generations. Direct inheritance of acquired peculiarities no scientific thinker now admits. Family peculiarities, however, are traceable through many generations. So striking a peculiarity as the possession of six fingers or six toes has been traced through a majority of the members of as many as five generations in a single family. And as has been said other family traits can be traced back in the same way. It would not be entirely surprising, then, if mental peculiarities and a predisposition to mental disturbance should be also a matter of inheritance. It is well known now that the physical condition of the brain substance may have much to do with the intellectual functions. Injuries to certain parts of the brain may cause special changes even of personal disposition. In the famous crowbar case, in which an iron drill over four feet in length was driven through one side of the head, it was noted that the man, who had been somewhat morose before, was inclined to be more amiable afterwards, but also had a tendency to be bibulous in his habits.