After the fall of Fort Sumter to Confederate forces in April 1861, Dr. Norman Smith predicted ''that means war and I will go tomorrow morning if called upon.'' And so he did, two days later, as surgeon of the Massachusetts ''Old Sixth'' Regiment when it answered Lincoln's first call for troops. Best known for its fight through Baltimore, when it was attacked by a secessionist mob and met with the first deaths of the Civil War, this historic regiment...