Other
Civil War Artillery Projectiles: Field Artillery Projectiles
A wealth of information about the projectiles used in artillery in both the North and the South. Included are pictures, cross-sections, and descriptions of the various types of projectiles.
World War 1
Worldwar1.com: Trenches on the Web: Big Guns of the Great War
This site from Trenches on the Web gives an overview of the different types of artillery used in World War I. Provides several thumbnail images of rail guns, howitzers and other forms of artillery, which can be enlarged by clicking on them.
Kidport
Kidport: Weapons of the Civil War
View images of individual guns and swords as well as artillery pieces used by Civil War soldiers.