An interesting mental feature of many insane patients is the imperative conception, or imperative impulse. This is a strong urging felt by the patient to commit a certain act. He may know the act is wrong and dread the punishment which he expects will follow its commission. But so constantly and strongly is he impelled that he finally yields and commits the act. Crimes are thus perpetrated by the insane, with a full knowledge of their enormity. The fact that such impulses undoubtedly exist should modify the common test, as to an insane person's responsibility before the law. The statute in many countries regards an insane criminal as responsible for his act, if he knows the difference between right and wrong. This decision is unjust and the basis is wrong; for an impulse may be overwhelming, and the patient utterly helpless during its continuance. However, a patient who has committed a crime under stress of such an irresistible impulse should be put under permanent custodial care. _Physical Signs of Insanity_ The physician who is skilled in psychiatry finds in very many insane patients marked physical signs. There are pains, insensitive areas, hypersensitive areas, changes in the pupils of the eyes, unrestrained reflex action, and partial loss of muscular control, as shown in talking, walking, and writing. Constipation and insomnia are very early symptoms of disease in a very large proportion of the insane. It is productive of no good result for a layman to try to classify the insane. The matter of classification will be for several years in a condition of developmental change. It is enough to speak of the patient as depressed or excited, agitated or stupid, talkative or mute, homicidal, suicidal, neglectful, uncleanly in personal habits, etc. _Illustrations of Various Types_ There are very interesting features connected with typical instances of several varieties of insanity, as they were noted in certain cases under the writer's care. A depressed patient with suicidal tendencies cherished the delusion that war with Great Britain was imminent, and that in such an event British troops would be landed on Long Island between New York City and the spot where he conceived the cattle to be kept. This, he argued, would cut off the beef and milk supply from the city. He therefore decided to do his part toward husbanding the present supply of food by refusing to eat; an act which necessitated feeding him through a rubber tube for many weeks. He also attempted suicide by drowning, throwing himself face downward in a shallow swamp, whence he was rescued. This young man was an expert chess player even during his attack.