restraint, and fulfils the legal interpretation of insanity. The employment of terms in an ambiguous sense has ever been the bane of philosophy, and the obstacle to its advancement. Without the meaning of important words be accurately defined, no general reasoning can be established. On some occasions the term UNSOUND MIND has been introduced, and considerable emphasis has been laid on it by lawyers; as possessing an intrinsic meaning, and designating a peculiar state of morbid intellect, not _precisely similar_ to insanity, but of equivalent effect in depriving a person of the management of himself and affairs. It is of the utmost importance that the term _unsound mind_ should be fully and accurately considered. Had this term originated from medical persons, it is most probable they would, at least have endeavoured to explain it; but it is of higher descent, and adopted by those luminaries of the law to whom we look up with confidence and respect. The force and extent of the term unsound mind are described in the luminous judgment of the present Chancellor on a recent case. Of this learned exposition of the law, every medical practitioner should be informed, as it will serve to guide him, when he is called to give his deposition on the state of a patient’s intellect. In the judgment adverted to, his Lordship observes, “I have searched, and caused a most careful search to be made into all the records and procedures on lunacy which are extant. I believe, and I think I may venture to say, that originally commissions of this sort were of two kinds, a commission aiming at, and enquiring, whether the individual had been an ideot ex nativitate, or whether, on the other hand, he was a lunatic. The question whether he was a lunatic, being a question, admitting in the solution of it, of a decision that imputed to him at one time, an extremely sound mind, but at other times an occurrence of insanity, with reference to which, it was necessary to guard his person and his property by a commission issuing. It seems to have been a very long time before those who had the administration of justice in this department, thought themselves at liberty to issue a commission, when the person was represented as not being ideot ex nativitate, as not being lunatic, but as being of _unsound mind_, importing by those words, the notion, that the party was in _some such state_, as was to be contradistinguished from idiotcy, and as he was to be contradistinguished from lunacy, and yet _such_ as made him a proper object of a commission _in the nature_ of a commission to enquire of idiotcy, or a commission to enquire of lunacy. From the moment that that had been established, down to this moment, it appears to me however to have been at the same time established, that whatever may be the degree of weakness or imbecility of the party—whatever may be the degree of incapacity of the party to manage his own affairs, if the finding of the jury is only, that