NEW YORK. May 24. — Mrs. Margaret Weaver Horton, the young woman with whom Dr. Arthur Warren Waite, confessed poisoner of his wife's parents, studied languages and music and shared a studio in a fashionable New York hotel, described late today at Wall's trial for murder what she considered the dual character of the prisoner. This alleged lack of nature of Walter, the evil side of which he has asserted manifested itself in the form of a little man from Egypt, gave the first inkling of the theory upon which Walter lawyers will proceed in their efforts to prove he was insane at the time he killed John E. Peck, and thereby save him from the electric chair.
Mrs. Horton, who cast sorrow in glances at Walter as he sat pale and outwardly in the case, told her story slowly and directly, and gave the impression that she cared little for the ordeal to which she herself was subjected. It appeared to those who watched her closely that she was trying to convey to the prisoner something of the sympathy she felt for him.
Although called as a witness for the State, Mrs. Horton seemed to be much relieved when Walter R. Deul, counsel for Walter, began to cross-examine her. Walter, who had sat almost motionless throughout the long, direct examination by Assistant District Attorney George N. Brothers, dropped his hand.  From his chin and raised his eyes towards the witness. The wife of the prisoner, dressed in deep mourning, and sobbing quietly at intervals, sat directly behind the Jury box. 