=Mania with Lucid Intervals.=--In many cases mania is intermittent or recurrent in its nature, the patient in the interval being in his right mind. The question of the presence or absence of a lucid interval frequently occurs where attempts are made to set aside wills made by persons having property. In these cases the law, from the reasonableness of the provisions of the will, may assume the existence of the lucid interval. A will made during a lucid interval is valid. When an attempt is made to set aside the provisions of a will on the ground of insanity in a person not previously judged insane, the plaintiff must show that the testator was mad; when the provisions of the will of a lunatic are attempted to be upheld, the plaintiff must show that the will was made during a lucid interval. A testator is capable of making a valid will when he has (1) a knowledge of his property and of his kindred; (2) memory sufficient to recognize his proper relations to those about him; (3) freedom from delusions affecting his property and his friends; and (4) sufficient physical and mental power to resist undue influence. The fact of a man being subject to delusions may not affect his testamentary capacity. He may believe himself to be a tea-kettle, and yet be sufficiently sound mentally to make a valid will. =Undue Influence.=--Persons of weak mind or those suffering from senile dementia are often said to have been unduly influenced in making their wills, and subsequently their dispositions are disputed in court. Before witnessing the will made by such a person, the medical man should satisfy himself that the testator is of a 'sound disposing mind.' This he will do by questioning, and his knowledge of the home-life of the patient will either confirm or set aside the idea of influence. A person who is aphasic may be competent to make a will. He may not be able to speak, but may understand what is said to him, and may be able to indicate his wishes by nods and shakes of the head. Ask him if he wishes to make a will, then inquire if he has L10,000 to leave, then if he has L100, and in this way arrive approximately at the sum. Then ask him if he wishes to leave it all to one person. If he nods assent, ask if it be to his wife or some other likely person. If he wishes to divide it, ascertain his intention by definite questions, and, having ascertained his views, commit them to writing, read the document over to him, and ask if it expresses his intentions. That being settled, a mark which he acknowledges in the presence of two witnesses, preferably men of standing, will constitute a valid document.