Dana Lombardy on “The Long Arm of Mr. Lincoln’s Army”
Dana presented diagrams and data to show how the artillery evolved in the Union Army of the Potomac during the American Civil War, and compare its effectiveness to the guns used by their primary opponent, Robert E. Lee’s Confederate Army of Northern Virginia. Gun types, numbers and organization, plus a look back at Napoleon’s artillery at Waterloo were also covered.
Tom Roza provided the following summary of Dana’s talk.
The presentation focused on the use of artillery in the Civil war with an emphasis on how artillery was used at the Battle of Gettysburg (thus, the use of the phrase “Long Arm” for being able to inflict casualties from a long distance). Dana covered the evolution of artillery from the early 1800s to the Civil War period and how battle tactics adjusted as the firepower and accuracy of cannons improved.
Napoleon Bonaparte’s use of artillery served as the basis for study by all West Point students. Military commanders focused on establishing a ratio of cannons to the number of troops. The smaller the ratio (e.g., 250 troops for every cannon), the more devastating the effect of artillery on massed troop formations.
As manufacturing processes improved, cannons became easier to maneuver and required fewer troops to operate then. Cannons used during the Napoleonic Wars required up to 14 soldiers to operate them and were very difficult to maneuver especially where roads were non-existent or turned to mud by rain. By the Civil War, most cannons required only 8 soldiers and could more easily be maneuvered.
At the beginning of the Civil War, the Confederate military obtained a majority of their cannons by taking over abandoned Federal armories located across the South. Over time, the South did begin to manufacture its own cannon, but were never able to match the scale and capacity of the North.
Early use of artillery relied on the solid round shot. Cannons were aimed at mass formations of troops and inflicted casualties only along the path that the round shot travelled. A British artillery engineer named Henry Shrapnel invented the artillery shell called “case shot” which was a shell that contained explosives and other metallic materials that exploded and spread out debris over a wider area (thus the term shrapnel was coined).
Case shot increased the effectiveness of artillery fire because once the shell exploded, it could inflict damage over a wider area as opposed to solid shot whose damage was only along its travel path. Artillery shell manufacturers continued to develop shells with more devastating affect packing into the shells small round iron balls, nails, bolts, and any other metals that could inflict severe injury.
The accuracy of solid shot and case shot was very erratic because the shape of the shell was not aerodynamic. Eventually, the rifled cannon was developed and along with that the rifled artillery shell which looked like a bullet used in a rifle or handgun. The rifled cannon and shell significantly increased the accuracy of cannon fire and made it a more deadly long-range weapon in combat.
Artillery shell technology continued to develop with the invention of the fuse plug which was used extensively in Civil War artillery. The fuse plug had markings on its exterior that measured in seconds how long it would take for the fuse plug to burn down before igniting the gun powder inside the artillery shell causing it to explode. Experienced artillery gunners would measure where the shell exploded in proximity to the target and then either shorten or lengthen the fuse plug before putting the shell into the barrel of the cannon.
The Effect of Artillery Fire and Artillery Tactics
When many cannons were used in an artillery barrage, a dense volume of smoke would often cover a battlefield. Troops would call this phenomenon “The fog of war”. This fog from artillery fire often obscured targets and many shells often missed their targets as a result.
In the early part of the 19th century, artillery fire had devastating effect on massed formations of troops that methodically marched towards the enemy’s front. Over time, military tactics began to change and large-scale charges of troops against massed artillery were used less and less. As a result, during the Civil War, the percentage of casualties caused by artillery was quite small. For example, at the battle of Gettysburg, the weapon that caused the most casualties was the rifle musket.
There were significant differences between how the North deployed its artillery battalions and how the South deployed them. The North did assign a small number of cannons to each infantry and cavalry unit. But, the Union Army also maintained a large Artillery Reserve from which artillery battalions would be dispatched to wherever in the battle they were needed.
The South, especially the Army of Northern Virginia under Robert E Lee had no artillery reserve. Instead, Lee spread his artillery battalions across his 3 infantry Corps and his cavalry units. This allowed Lee to get more of his artillery engaged in battle sooner because it was already part of the unit engaging the enemy. This advantage was readily apparent on Day 1 of Gettysburg when the South had its artillery units engaged, but the North’s Artillery Reserve under General Henry Hunt was still miles to the south of Gettysburg.
The Confederates were initially successful at Gettysburg because of a military term called the “Force Multiplier”. This comes into effect when one side has more artillery than the other side as was the case on July 1 and for a portion of July 2 when the South came closest to actually winning the Battle of Gettysburg.
However, by Day 3 of Gettysburg, the Union Artillery Reserve was on the field. Union General Henry Hunt positioned 80 cannons along Cemetery Ridge in advance of Pickett’s Charge. This proved to be a critical factor in preventing a Confederate breakthrough of Union lines on Cemetery Ridge.
There were two artillery related factors that directly led to defeat of Pickett’s Charge: First, E. Porter Alexander’s incorrect assessment of the effect of his own artillery barrage on Union forces; Second, the impact on Confederate troops of marching almost a mile across open ground under the constant barrage of 80 Union cannons.
The fog of war caused by both side’s massive artillery barrage that preceded Pickett’s Charge prevented E. Porter Alexander from making an accurate assessment of the results of his artillery fire. Through the smoky haze, Alexander observed the Union removing batteries off Cemetery Ridge. Alexander interpreted this as the Union retreating from its position and advised Longstreet to start Pickett’s Charge. In fact, what Union General Henry Hunt was doing was replacing worn out batteries with fresh batteries. The effect was devastating on Confederate forces.
This leads to the second reason that Pickett’s Charge failed. Historian for years wondered why there were not more Confederate casualties associated with Pickett’s Charge. After all, over 13,000 Confederate infantry from 3 Southern divisions made the charge – why were there not more casualties? It was determined that because of the devastating effect of the 80-gun Union artillery barrage, many Confederate soldiers just stopped moving forward. Many laid down on the ground and took shelter and when it became clear the attack was failing, they got up and went back to their lines own seminary Ridge.
Dana Lombardy was an Associate Online Editor for Armchair General magazine and now does research, writing and design through Lombardy Studios. Dana is best known for his nearly twenty television appearances, including multiple episodes of The History Channel’s “Tales of the Gun” series. He has contributed as an editor, cartographer, graphic artist and designer on many books, games, and magazines, and was Publisher of Napoleon Journal from 1996-2000.