They Ate at Longwood Yesterday, Anyway, even though the rain postponed all competition in the national doubles championships. In a clockwise direction, starting at lower left - Dr. Herbert Fischer of Wayne, Pa., a veterans' doubles survivor; Jack Van Den Eynde of Belgium, who scared the defending champions on Thursday; Alejo Russel of Argentina, who has reached the quarter-final round; William Nassau of Paoli, Pa., second-seeded in the veterans' with Dr. Fischer as his partner, and Andre Hammersley of Chile, who bowed out earlier in the week.