Ager and Williams Guns (Civil War)
Check out the following page for some great historical information on various approaches to rapid fire weapons in the Civil War including carbines, revolving rifles, Union and Confederate volley guns, the Williams gun, and the Ager Gun.
The highlights of the page are step-by step description with photos from a gentleman who has built working replicas of the Ager and Williams Guns! http://www.floridareenactorsonline.com/Weapons.htm