As promised, I have placed all of this together in one place to make it easier to understand: topography, cross-sections and photos. Click on the header bar above under Technical Data.
This concludes PART 1 of my research into the Swale at Mercer Square. PART 2 focuses on the actual weapons used by the soldiers during the battle of Fredericksburg and the impact of the parabolic arc trajectory of the bullet on my initial findings.
Yes, the Swale at Mercer Square does exist, but so what? Did it really save that many union soldiers with all that the confederates were throwing at them? Well, let’s look at it this way. There were reported to be seven individual brigade level union attacks upon the Sunken Road the day of the battle. Most were separated by 15 to 30 minutes, as each new Federal division sent out its brigades. Burnside’s troops came out of Fredericksburg and formed in the shelter of the bluff on the western side of the canal ditch. As each new assault came forward on the double, most of the confederates would have switched their attention to the new and emerging threat to their position on the Sunken Road. This being true, union soldiers, wounded or not who made it back to the swale would have been a lesser threat to the confederates. As a consequence, probably not shot at, even if seen. Confederate rifles would be reloaded in preparation for the next assault emerging from Fredericksburg. While the confederates had sufficient ammunition, the supply was not unlimited. Resupply of ammunition had to be hand-carried into position. This resupply generally arrived with the reinforcing regiments. This necessarily caused a certain level of ammunition conservation on the part of the confederate soldiers. In other words they would have fired less at the union survivors in the swale while awaiting the new attack. But, there was another problem.
Civil war bullets did not fly like the line of sight, straight as an arrow, flat and true. There was a parabolic curve to the path of a rifle musket and its .58 caliber minie’ball. Therefore the Zone of Protection I identified will potentially shrink. What is the real area in defilade where a union soldier was afforded protection from small arms fire? What are the characteristics of the civil war rifle musket? How can I best find the flight path of the bullet to improve the results of my investigation of the swale in Mercer Square? Beyond the parabolic arc of the bullet, what weapons were the confederate soldiers using in this battle? How did they influence the battle?
Exploring muskets and rifled muskets
Both the Union and Confederate governments recruited and armed troops in the Civil War. Initially they used existing armament stocks available in armories and depots. The Federal government ramped up manufacture of its Springfield rifle musket. The Confederate government set up manufacturing in Richmond, VA and Fayetteville, NC, but started from virtually zero. Both sides relied upon imported weapons from Europe to fill the vacuum in available weapons. Foreign governments were only too glad to be rid of outdated muskets and equipment in their inventory. This allowed foreign governments to literally update their armies at American expense. For my purposes, I focused upon three weapons; the Model 1842 smoothbore musket, the Model 1855/1861 Springfield rifle musket, and the Model 1853 Enfield rifle musket. In December 1862, these three weapons, or ones very similar, predominated in the eastern theater.
In the 1850’s, a technical revolution in arms manufacturing took place. The goal was to increase the range of the musket. This was accomplished by manufacturing with rifling. This had the advantage of increasing the effective range of the weapon from 75-100 yards for the smoothbore musket to 200-300 yards with the rifle musket. The bullet with rifling was rated at 1000 yards in early tests. At this range, it could penetrate three 1-inch pine boards spaced 12 inches apart. The challenge was seeing that far and judging the fall of the shot correctly. Early enthusiasts of the rifle musket predicted vast changes in the nature of warfare as the world knew it at that point. One such author was Lt Cadmus Wilcox of the 7th US Infantry, later Confederate General Wilcox. His book published in May 1859 makes interesting reading even today. http://books.google.com/books/about/Rifles_and_Rifle_Practice.html?id=JNtEAAAAIAAJ
He stressed the need for training soldiers to estimate range to target. This was not followed. This was a failing of both armies during the war. He and others foresaw battles commencing at 500 yards. It was thought that artillery and cavalry would be minimized on the future battlefields due to the ability of infantry to engage them at distance.
For specific technical information on the weapons look at the following:
The second part of the arms revolution was the creation of a bullet that would use the rifling effectively. A round musket ball could not. Claude-Etienne Minie, a French Army Captain is generally credited with solving the problem of using expanding gasses to force portions of the bullet into the rifle groves. From him, we get the term Minie-ball. There were others equally important in this development. Montgomery and Henri-Gustove Delivne also of the French army were his precursors. Captain John Norton proposed a cylindrical shape for the bullet which was fashioned by London gunsmith W. Greener, and it was upon this that Captain Minie capitalized upon. William Prichett of England developed the bullet used in the Enfield rifle musket. By the time of our civil war, the rifle musket and the minie-ball were state of the art for infantry in warfare.
Next time we will look closer at the trajectory of the minie-ball, the parabolic arc and the challenges it presented to rifle musket firing.