Book excerpt: Fifty years of service at the White House in various capacities, including bodyguard to Abraham Lincoln, William H. Crook's memoir brings an astonishing array of personal details of life in the executive mansion. His sensitive observations of Lincoln are especially moving. A well-known figure in Washington, Crook knew every president from Lincoln until Crook's death in 1915. He was a keen observer and his stories will entertain and sometimes surprise you. Here are also stories of presidents Andrew Johnson, Rutherford B. Hayes, and James Garfield. A friend of Ulysses S. Grant, a guest at the White House wedding of Grant's daughter, Nellie, he also tells stories of racing with Grant in buggies.