Although Friendship has been a theme of the ages, its nature and history have not been treated with any degree of fullness by any writer of the ages. Poets and philosophers and essayists have recognized the force and beauty of friendship as a human sentiment, from the days of Homer and Plato and Cicero to those of Bacon and Montaigne and Tennyson; but no one of them has attempted a careful analysis of its elements or a comprehensive record of its more important historic illustrations. Therefore it is that this volume is presented as a unique study of a subject that deserves greater prominence than has hitherto been accorded to it.