Book excerpt: A hearty eater, dapper dresser, bookseller to Loyalists and Patriots alike,and married into a staunch Loyalist family, Henry Knox may seem an unlikely hero.But his fascination with warfare and strategy and his support of the Patriot cause prepared him to do what no one else thought was possible: transport heavy artillery from Fort Ticonderoga, up and down snow-covered hills and across frozen lakes, to relieve the siege of Boston. The dramatic story of his achievements is all the more satisfying for being absolutely true, a little-known episode in the history of the American Revolution. Source notes, time line, bibliography, map.