FIELD DAY, a name given in the United States to a group picnic organized by large institutions. City schools, trade organ izations, corporations employing a large number of workers and city departments such as the police, make a practice of devoting a part or the whole of a day in spring to the field day. It is usually held in an outlying city park, or, in some cases, in State or private amusement centres lying at some distance from the city. The main attraction on field day is a series of athletic con tests, such as races, jumping contests and baseball games between individual groups within the organization. Medals, trophies and banners are given to the winners. In the case of corporations, the officers give awards to the winning employees. Police field days have some of the characteristics of military manoeuvres and sham battles, and serve to demonstrate to the public the high degree of training and discipline to which the police of large cities are subject.