In treating this most important class of affections, we must dismiss from our minds all those pre-conceived notions which we have been led to form of what constitutes mental derangement. We must view the subject as medical philosophers in the most liberal acceptation of the term, and not as _nisi prius_ barristers; we must consider ourselves at the bed-side of a suffering patient, demanding from our skill that relief which he is led to believe we have in our power to afford, and not as in a court of justice, undergoing an examination at the hands of a lawyer anxious to establish his case; and, above all, we must apply to the disease of the brain and its disordered manifestations those pathological principles which guide us in the elucidation of the affections of other organs. If we consider insanity not as a specific disease invariably exhibiting the same phenomena, but as it really is, the effect of a disordered condition of the sentient organ, having an incipient, as well as an advanced stage, we may, by a judicious application of the principles of therapeutics, succeed in many cases in crushing the disposition to suicide before it has taken a formidable hold of the constitution. In the great majority of cases the premonitory indications are well marked and unequivocal. The experienced physician and accurate observer will be able to detect, before the mental alienation becomes apparent to others, the early dawnings of derangement. He knows that it is frequently manifested by some change in the person’s usual healthy habits of thinking and acting,—by the exhibition of odd fancies and whims. Although surrounded by everything calculated to contribute to his happiness, he is the most miserable of human beings. Trifles annoy and irritate him; he sees in his dearest friends his deadliest enemies; talks of conspiracies, of plots, and stratagems; becomes suspicious of everything and everybody; his former objects of pleasure afford him no delight; he avoids society, and is occasionally heard muttering strange things to himself. In the majority of cases these are the early dawnings of cerebral disease leading to unequivocal insanity, and yet so tied down are we to definitions, arbitrary standards and poetical tests, that we will not admit derangement of mind to be present until the symptoms are so self* evident and glaring that the condition of the mind becomes apparent to the most superficial observer. When this view of insanity is recognised as orthodox, and moral treatment adopted in the early stages of the disease, much good may be expected to result.