Sufficient provision for heating, evenly distributed, must be made. When a corridor or lobby is warmed, rooms are more evenly dealt with and less liable to cold draughts. If a school be wholly warmed by hot water, radiators are recommended. Fireplaces in addition are useful for extra warming, and the flues for ventilation. A stove with pipe through wall or roof can under no circumstances be permitted, and is only approved when provided with proper chimney, or of such pattern that it cannot become red hot or otherwise contaminate the air. It must be supplied with fresh air direct, by a flue not less than 72 inches super., and not of a size or shape to interfere with the necessary floor space for teaching. Fireplaces, where used, are best in corners, to leave space for a teacher's desk, blackboard, etc.