battlefields was laid to the breaking of gun-carriages.
The Ordnance Department, however, was able to supply the deficiencies as soon as its own plants were running, and artillery officers thereupon expressed their complete satisfaction.
The field-guns were of two kinds — the 3-inch wrought-iron (10-pounder) rifle and the smooth-bore Napoleon
The first was made by wrapping boiler-plate around an iron bar to form a rough cylinder, welding it together, and then boring it out and shaping it up. The second was generally made of bronze, cast solid, then bored and prepared.
For short ranges in rough country, the Napoleon
gun was preferred to the rifle, as it carried heavier charges and the use of canister in it was more effective.
The siege-guns, in which mobility was less important, were of cast iron.
Owing to the length of bore and the relatively small diameter, these guns were also usually cast solid.
One of these pieces, the Parrott, was strengthened by a wrought-iron cylinder shrunk over the breech.
Sea-coast guns were generally of cast iron, and the best types were cast hollow and cooled by the Rodman process of playing a stream of water on the interior of the tube while the exterior was kept hot, thus regulating the crystallization of the iron and increasing its durability.
To some of the sea-coast guns the Parrott principle of construction was applied.
The imperfectly equipped batteries which were left to the Army of the Potomac after the First Bull Run
consisted, as has been noted, of only thirty guns.
These had six hundred and fifty men and four hundred horses.
When the army took the field, in March, 1862, the light artillery consisted of ninety-two batteries of five hundred and twenty guns, twelve thousand five hundred men, and eleven thousand horses, all fully equipped and in readiness for fieldservice.
Of this force, thirty batteries were regular and sixty-two volunteer.
During the short period of seven months, all the immense amount of necessary materiel had been issued and