The Photographic History of The Civil War: in ten volumes, Thousands of Scenes Photographed 1861-65, with Text by many Special Authorities, Volume 5: Forts and Artillery.
Francis Trevelyan Miller, Ed.

Until the middle of the nineteenth century there was but little improvement in cannon or gunpowder. One reason for this was that bronze and iron were used for making guns, and these metals could not withstand the exceedingly great pressures of heavy charges of powder unless the cannon were cast so large as to be unmanageable. No scientific treatment of the subject of gun-strains had been attempted previous to this time, because it was assumed that all the powder in a charge was converted instantaneously into gas.

Powder and ball for small arms were originally carried loose and separately. Gustavus Adolphus, King of Sweden, first made an improvement by providing separate receptacles for each powder charge; these were called cartridges (Latin carta, or charta) from their paper envelopes. He subsequently combined the projectile with the powder in the paper wrapper, and this, until about 1865, formed the principal small-arms ammunition.

However, not all of the ammunition used in the Civil War was prepared in this form, and from the fact that powder and ball were carried separately arose the danger of inadvertently loading the piece with more than one charge at a time. Even in the use of the two in one package, inasmuch as there was usually nothing to prevent the reloading of the gun before the previous cartridge had been fired, there still remained this danger. As a consequence, it was reported that nearly half of the muskets abandoned on the field of Gettysburg were found to contain more than one load, and some of