One of the most interesting and significant sources, which in the search for material on the history of business is generally tapped in vain, is the diary or autobiography of the American business man. All too often he leaves behind him copious accounts of his travels, his philanthropies, his religious, political and cultural interests, but fails to bequeath to posterity other than fragmentary records of that which is most important of all from the social point of view, his business activities. The successful business man works not only in order to secure a competency which will enable him later to devote himself to his real interests in life, such as art and politics; whether he knows it or not, business is in most cases his real interest and his real talent. How worthwhile it would be, therefore, to read his own accounts of that activity, of his true vocation, which he understands and can interpret for those of later generations as no one else can do.