Even though June 3, 1864 at Cold Harbor is best recalled as an infantryman’s fight, as mentioned yesterday, the Fifth Corps artillery launched over eighteen tons of ordnance towards the Confederate lines. While massed batteries, as done with great effect just miles to the south at Malvern Hill in 1862, was not an applicable tactical option, the artillery remained an important combat force on the battlefield. But field fortifications, even basic trenches, provided some mitigation against traditional field artillery. With earth and wood protecting the soldiers from direct fire, the infantry could better withstand any eighteen tons of shot and shell the enemy might care to throw over.
Increasingly, not just in the Civil War but across the scope of warfare, vertical fires became more important where fortifications came into use. In the Second Corps sector of the Federal lines, mid-day on June 3, Colonel John C. Tidball employed Coehorns in close proximity to the Confederate lines. Captain James H. Wood, 4th New York Heavy Artillery, commanded the six mortars assigned to the Second Corps. Wood wrote:
At 12 m. 3d of June one section (two pieces)was first placed in position at Cold Harbor, at a distance of about 800 yards from the rebel lines. The charge of powder used was 6 ounces and the length of fuse 15 seconds. The mortars were stationed in a hollow in rear of a belt of woods; 80 rounds were fired. It was reported by the front line of battle and the skirmishers of the Union forces that the shells made great havoc with the enemy, nearly every one exploding in their midst. At 7 p.m., by suggestion of General Barlow, the entire battery withdrew to the rear.
But the mortars would return. That night the Federals completed mortar positions just 150 yards from the Confederate lines. When the morning broke with heavy musketry, the mortars were ready:
At this place the charge of powder was 2 ½ ounces and the length of fuse 7 ½ and 8 seconds. The effect was excellent, and in about half an hour the rebels ceased to fire entirely. The position was such that the damage caused by the explosion of the shells was plainly discernible; and it was reported furthermore by our skirmishers that great execution ensued and the utmost consternation was visible among the enemy. The battery was highly complimented by Major-General Barlow and Brigadier-General Owen.
But their work soon attracted Confederate attention. Confederate field artillery fired in an attempt to damage or destroy the mortar battery. But being so low and behind works, this did little good. Confederate sharpshooters were more effective, preventing the gunners from standing up to aim or manage the mortars. As a counter, the mortars began firing on the sharpshooters:
It was determined to try the effect of the mortar shells upon them and the whole battery delivered its fire, with the same charge of powder and length of fuse as at first. The result was almost instantaneous. Their firing was suppressed and was not resumed for several hours. It is perhaps not improper to observe that, during this affair, 2 rebels were seen to be blown 10 feet into the air, with heads detached. Their companions wildly scattered in every direction, and our infantry (General Owen’s brigade) giving a cheer, delivered a volley with telling effect.
Afterward the Confederates treated the mortars with caution. Wood observed, “… that the enemy had fallen back in front of the mortars, leaving but a few skirmishers and sharpshooters in their front line of breast-works.” In effect, the mortars had created a zone in which the Confederates could not operate. While not a large zone, at least that offered some tactical advantage to the Federals. But the Federals would need many more Coehorns if this was to be a useful advantage.
On the other side of the lines, the Confederates likewise started looking to vertical fires. At that time, the Army of Northern Virginia lacked Coehorns. But, Brigadier-General William N. Pendleton noted in his report on the campaign one adaptation of field artillery to the need. “A 24-pounder howitzer of McIntosh’s battalion was adjusted a little in rear of the line and served as a mortar. It did good service in annoying the enemy’s working parties.”
Soon the howitzer and the Federal mortar began exchanging fires, as Wood recorded:
… the rebels fired at our forces with good range, using what was supposed to be a 24-pounder howitzer, trained as a mortar. The projectile thrown was spherical case-shot, by the explosion of one of which a man and a mortar were struck, but no serious damage was done to either. A new supply of ammunition having been received, it was decided to silence the rebel machine, if possible. By observing the smoke of their discharges, it was estimated that the distance was about 800 yards. A charge of 6 ounces of powder and a 15-second fuse were used, and after about one dozen discharges the enemy’s machine was silenced.
Wood’s mortars continued to do good work during the fighting at Cold Harbor. The gunners had become very well practiced in the art of laying shells where needed. Later, the mortars engaged in some more counter-battery fire, with good results:
On the 11th the remaining section, in charge of Captain Jones and Lieutenant Moore, was employed in firing at a rebel battery of light 12-pounders, which had opened upon a Union battery a short distance to our left. The mortars were estimated to be about 800 yards from the rebel battery. The charge was 5 ½ ounces and the length of fuse 15 seconds. The first shot struck on the left of the battery on a sand-bag breast-work, tearing a large hole therein. Another exploded inside the parapet, another in rear of the battery, another a short distance to the right. Assisted by the Union battery (light 12-pounders), the enemy’s guns were silenced. After this a few shells were thrown into a house almost in front of the mortars and 300 yards distant. The charge was 3 ½ ounces and the fuse 10 seconds in length. The house was a refuge for sharpshooters. One shell broke through the roof and exploded in the house. No more shots were observed to come from that locality.
With both armies remaining in close proximity for more than a week, the mortars were an idea weapon to use. But there were precious few of them at the front. Back in Massachusetts, Ames Manufacturing had a batch of fifty of the little mortars ready for inspection. More Coehorns were on the way.
(Citations from OR, Series I, Volume 36, Part I, Serial 67, pages 527-8, 1050.)