From "American Civil War artillery, 1861-1865: Heavy artillery" by Philip Katcher, Tony Bryan.
In 1866, the Army of Northern Virginia corps artillery chief, E. Porter Alexander, describes the variety of mortars Southern field armies used: "During the siege of Petersburg a number of iron twelve and twenty-four pounder Coehorn mortars were made and rendered excellent service. Wooden mortars were also made and tried for short ranges, but even when they did not split, the ranges were so irregular that they could not be made useful." Confederate artillerymen at Petersburg ran short of friction primers but continued firing their mortars by heating priming wires red hot and inserting them in the vents.
Mortars were useful in siege situations, but were not always available to field armies. Therefore, artillerymen often improvised by using tree trunks for their mortar tubes. According to a Union report of the siege of Knoxville: "The repeated assaults upon the fort, and the close proximity of the enemy's rifle pits, made it very desirable to mount two or three mortars for the purpose of shelling out the enemy's trenches. As none were on hand, a wooden mortar was constructed, capable of throwing a 24-pounder howitzer shell. It was made of live white oak, 2 1/2 feet in diameter, and when finished, the thickness of the wood was 1 foot and in the rear of the seat of the charge from 18 inches to 2 feet. It was hooped with three iron bands shrunk on and mounted on a bed of oak. It was fired with a 24-pounder howitzer shell and 7 ounces of powder, and withstood the test admirably; but subsequently, being fired with the same projectile and 16 ounces of good powder, it burst in two."
I doubt that many of the artillerymen sought the honor of being the one chosen to pull the lanyard attached to the friction primer inserted in one of these wooden mortars.
