Abraham Lincoln wrote to his law partner, William Henry Herndon, that ?the physical side of Niagara Falls is really a very small part of that world?s wonder. Its power to excite reflection and emotion is its great charm.? That statement might fittingly be applied to Lincoln himself. One who lived in his time, and who has read the thousand books they say have been written about him in the half century since his death, may still be dissatisfied with every description of his personality and with...