One of the Associated Factory Mutual Fire Insurance Companies, Often Called the "New England Mutuals" Or the "Factory Mutuals": an Association of Manufacturers for the Prevention of Fire Loss. One of the Oldest and Most Successful Organizations for the Conservation of Resources: The Development of the Prevention Idea from Its Beginning to the Present Time is Told Herein, that Its Story and Lessons May be More Widely Known: An Ounce of Prevention is Worth a Pound of Cure