On investigating those cases reported by English, in which the patient was compelled to take on lighter work or change his vocation, one at once encounters a diversity of symptoms, some so indefinite as to be included under the term traumatic neurasthenia, others so distinct as to fall naturally under certain well-recognized groups, such as traumatic cephalalgia, epilepsy, &c. =Traumatic neurasthenia.= All those cases characterized by the indefinite nature of their complaint require the most careful sifting--to separate the wheat from the chaff--for there is always a certain proportion of malingerers, such as realize the pecuniary advantages of their position. When these are excluded, a large class remains in whom the injury must undoubtedly be regarded as the _fons et origo mali_. A curious and interesting train of symptoms supervene after the accident, indefinite from a localizing point of view, but quite definite from the standpoint of the patient himself. Mental irritability, with a ready tendency to fly into a passion--Kaplan’s explosive diathesis--may be regarded as an almost constant symptom. The patient is changed in his manner towards those near and dear to him, restless, irritable, and intolerant of noises, morose, and incapable of managing his financial affairs. The change may be insidious in origin, but, in the absence of appropriate treatment, steadily progressive. The mental changes, unless checked in time, tend to merge into definite insanity, not infrequently of a homicidal or suicidal character. Insomnia, with terrifying dreams, loss of appetite, emaciation, headache, vertigo, nervousness, amnesia, lack of power of mental concentration, and mental depression are all noticeable features. All such symptoms are aggravated by indulgence in alcohol, exposure to the sun, &c. From a localizing point of view the symptoms are obscure, but they are probably none the less dependent on pathological changes--thickening of the meninges, effusion into the subdural and subarachnoid spaces, œdema of the cortex, &c. Furthermore, it will usually be found that, during the height of the attacks, the pulse-rate is slowed, the temperature raised, and the respiration embarrassed--symptoms suggestive of cerebritis and alterations in the intracranial pressure.