Railroad Math, Why Chattanooga Mattered

Rhea Cole

1st Lieutenant
Joined
Nov 2, 2019
Location
Murfreesboro, Tennessee
“Professionals discuss logistics, amateurs discuss tactics.” Was something an ROTC instructor said that stuck in my mind because it seemed so odd to me at the time. When I owned a business that involved goods that were shipped from Japan & later was sending container loads to Great Britain, I received a real life lesson in exactly what my instructor had meant.

Civil War railroading is a buffet of fascinating topics to explore. Living as I do in Murfreesboro TN, the historic Nashville & Chattanooga RR & present day CSX Railroad are an everyday reality. I often cross the single track mainline going to & from errands. By the same token, you can’t study the Civil War in Tennessee without constantly criss crossing the N&CRR. While chatting with a retired RRer recently, he said something that opened my mind to a new understanding of why Chattanooga was so vital to the CSA logistical system.

Hundreds of thousands of pounds of bacon & corn were shipped on rails from the Atlanta Depot to the Army of Northern Virginia via Chattanooga. What my friend said that caught my attention was that every boxcar that carried freight from Atlanta to Virginia went through Chattanooga three times. He called it railroad math. Customers only care about when an empty car is loaded & when it is unloaded, the RR cares about what happens in between. Every 100 miles a loaded car travels is equal to 300 RR miles.

As we all know, once Lee became head of the Army of Northern Virginia he took a through the soda straw focus on the needs of his command vs the overall strategic needs of the CSA. I have listened to very knowledgeable historians debate exactly what it was that motivated Lee to send Longstreet to Chattanooga. We know that in retrospect he would have sent Longstreet to Knoxville. He could have been supplied from Atlanta via the link to Knoxville. Holding Knoxville & threatening Chattanooga with a secure supply line would have revolutionized the situation. In either case, what was it about Chattanooga was it that Lee thought was worth fighting for? Was RR math also RE Lee math?

The Atlanta to Virginia logistical system was a one way, point to point operation. An empty car had to be returned to Atlanta where it was loaded, returned to Virginia & sent back to Atlanta. From the RR’s point of view, it took three trips to deliver a single load of bacon to Lee’s army.

My RRer friend believes that the additional distance it took to deliver the absolutely vital supplies from Atlanta to Virginia is why Lee relented & allowed Longstreet to be sent to Chattanooga. It was simple RR math.

In round numbers, the loss of the direct route between Atlanta & Virginia added 500 miles one way. Using RR math, that was a 1,500 mile net additional mileage/round trip. Anybody familiar with the decreasing ability of Southern RR’s to operate understands what a blow the loss of the direct line was.

Not only did the loss of Chattanooga mean that it took considerably longer & his reduced the number of loads that could be dispatched, the maintenance downtime per load increased. Just by loosing Chattanooga, the gross tonnage of supplies that could be transported from Atlanta was severely restricted. The South had no possibility of stepping up frequency to overcome the time delay, this assets simply did not exist. Quite the contrary was true, the increased distance wore out existing equipment & further restricted the flow of supplies. The net impact of the loss of Chattanooga was longer wait times between deliveries & fewer cars/locomotives to carry the freight.

Loosing Chattanooga was a disaster for the CSA on any number of levels. The inexorable effect of RR math is a new one to add to the list & one that the CSA couldn’t bear.
 
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wausaubob

Lt. Colonel
Joined
Apr 4, 2017
Location
Denver, CO
In that era railroads were valued based on what the investors had put into the business in terms of bonds or stocks, not based on the net revenue stream they could generate. The equipment could and did depreciate, but the locations in the cities and towns and the inter connected right of ways, including the engineering at each river crossing, were permanent. A railroad could and did regularly rebuild as long as it owned the right of way. Under the accounting systems that existed at the time, the railroads seemed to be worth only about $1B.
In contrast the slaves were valued based on the prices generated at major slave auction centers like in New Orleans. They were valued at the theoretical sale price, even though as someone has commented, in the middle 8 states, many of the slaves were not for sale at any price.
The more accurate way of looking at it was that the railroads were capable of generating an infinite amount of revenue that was dependent not only on the strength of the cotton market, but on the total economic health of the US.
And as you noted, the direct routes were worth much more than the indirect routes. The direct routes were cheaper to maintain and required fewer engine miles, and in that era engine maintenance was a large expense.
Some of these places that did not seem very important based on the size of the town were very important for the efficiency of the railroad system. In the north it would have been places like Toledo, OH or Altoona, PA. In the southern areas, places like Atlanta, Chattanooga and Nashville, despite being very small towns, had critical switching yards, roundhouses and machine shops that were extremely valuable.
Once General Sherman's forces occupied Atlanta, and the US siege covered the Weldon RR which was the direct route south from Petersberg, the Confederacy had to control the Shenandoah Valley. Why? Because it was close to Richmond. And the Confederacy was running out of locomotives.
 
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wausaubob

Lt. Colonel
Joined
Apr 4, 2017
Location
Denver, CO
Politicians and journalists in the 1860s liked the big battles and the blood that was spilled. But those big battles could have gone on for a very long time before the Confederates were persuaded they had lost.
The US had to close the last two blockade ports and disassemble the Confederate railroad system before the armies and the people were going to give up.
 
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wausaubob

Lt. Colonel
Joined
Apr 4, 2017
Location
Denver, CO
The Confederacy did not have a king, who was constantly computing the costs vs the possible benefits of continuing the fight. And there was very little democratic restraint on the government by the poor people who were doing the fighting and dying. In the US Civil War this situation was made even worse by the fact that the areas in which dissent against the Confederate government was strongest were either re-occupied by the US, or so distant from Richmond, like the Red River district of Texas, that they had no impact on Confederate policy.
 

DaveBrt

2nd Lieutenant
Joined
Mar 6, 2010
Location
Charlotte, NC
What my friend said that caught my attention was that every boxcar that carried freight from Atlanta to Virginia went through Chattanooga three times. He called it railroad math. Customers only care about when an empty car is loaded & when it is unloaded, the RR cares about what happens in between. Every 100 miles a loaded car travels is equal to 300 RR miles.

The Atlanta to Virginia logistical system was a one way, point to point operation. An empty car had to be returned to Atlanta where it was loaded, returned to Virginia & sent back to Atlanta. From the RR’s point of view, it took three trips to deliver a single load of bacon to Lee’s army.

My RRer friend believes that the additional distance it took to deliver the absolutely vital supplies from Atlanta to Virginia is why Lee relented & allowed Longstreet to be sent to Chattanooga. It was simple RR math.

In round numbers, the loss of the direct route between Atlanta & Virginia added 500 miles one way. Using RR math, that was a 1,500 mile net additional mileage/round trip.
I don't understand your friend's math. An empty car sits in Atlanta, is loaded and sent to Richmond, unloaded, loaded with outgoing supplies to Atlanta. When the car arrives in Atlanta, it has made 2 trips, loaded both times. If there was no outgoing freight from Richmond (rare, but possible), there was still only a pair of trips involved -- Atlanta to Richmond and Richmond to Atlanta. I assume your friend is sending an empty car to Atlanta to start the trips, but empty cars to Atlanta were unheard of.

The direct route from Atlanta to Richmond was 760 miles; the route through central South Carolina was 700 miles. The eastern route was slower because of the change of gauge at Charlotte and the vastly increased number of freight inputs into the transportation flow -- Charleston, Wilmington, Petersburg, Columbia, Charlotte, Raleigh -- all traffic on the eastern route.
 

DaveBrt

2nd Lieutenant
Joined
Mar 6, 2010
Location
Charlotte, NC
I have listened to very knowledgeable historians debate exactly what it was that motivated Lee to send Longstreet to Chattanooga. We know that on retrospect he would have sent Longstreet to Knoxville & then advanced on Chattanooga. In either case, what was it about Chattanooga they Lee thought was worth fighting for?

The South had no possibility of stepping up frequency to overcome the time delay, this assets simply did not exist. Quite the contrary was true, the increased distance wore out existing equipment & further restricted the flow of supplies. The net impact of the loss of Chattanooga was longer wait times between deliveries & fewer cars/locomotives to carry the freight.
The initial Longstreet trip was to be THROUGH Knoxville, not stopping there. It was always the plan to have Longstreet fight with the AOT, not on its own.

The loss of the Knoxville route cost the South its best route from Atlanta to Richmond, but it cost only a handful of cars and engines (those captured in Knoxville). The surviving East Tennessee & Virginia RR rolling stock was taken up and operated by the Virginia & Tennessee RR; the East Tennessee & Georgia RR rolling stock was moved to a new company headquarters in Augusta, from which they were employed carrying freight (especially blockade runner cotton) into the Carolinas.
 

Coonewah Creek

First Sergeant
Joined
Jun 1, 2018
Location
Northern Alabama
During the beginning of the Atlanta Campaign, Sherman realized his dependence on the single-track railroad back to Chattanooga and Nashville. Sherman determined to stockpile supplies at field depots along the railroad to be prepared to move them to the troops by wagon train when necessary. Prior to the start of the campaign, it had been determined in a conference with his logistical team, that Sherman would need 130 railroad cars, each carrying 10 tons of supplies, arriving at Chattanooga each day to supply the army. This requirement took into effect expected losses by accident and raids, and even provided for a reduced amount of forage for the horses and mules (note that the calculations Sherman used were based on 100,000 men and 35,000 animals. His Quartermaster’s report for July 1, 1864 showed closer to 60,000 animals with the army and, if non-combatants were included, his army probably numbered closer to 125,000 men). Beef cattle and troop reinforcements would be forced to walk rather than take up space on the limited railroad cars. Despite howls of protest, Sherman also issued orders strictly limiting the railroad’s use to military and not civilian, requirements. Even then there were concerns that there was too little rolling stock and too few locomotives to meet the task. Prior to the start of the campaign, there were only about sixty serviceable locomotives and six hundred cars available. At least one hundred locomotives and one thousand cars would be required.[1] Revealing a quick temper and absolute impatience with those who obstructed or clung to the letter of regulations, Sherman is reported to have retorted to one such officer, “If you don’t have my army supplied, and keep it supplied, we’ll eat your mules up, sir – eat your mules up.”[2]

Before the end of April, Quartermaster General Montgomery C. Meigs had reported the accumulation of enough food at Nashville for 200,000 men for four months, and grain enough to feed 50,000 animals through the rest of the year. Also, rolling stock and locomotives were being built-up at the rate of fifteen new cars and one new engine per day.[3]



[1] Sherman, Memoirs, p. 467-469. George Edgar Turner, Victory Rode the Rails: The Strategic Place of the Railroads in the Civil War (Lincoln, NE, 1953), pp. 325-326. James A. Huston, The Sinews of War: Army Logistics 1775-1953 (Washington, D.C., 1997), p. 234-235. It should be noted that Louisville, Kentucky remained Sherman’s base for the entire campaign while Nashville and Chattanooga expanded into secondary bases. Other advance depots were located at Johnsonville and Knoxville, Tennessee and were involved in supporting Sherman’s drive on Atlanta.
[2] B.H. Liddell Hart, Sherman: Soldier, Realist, American (New York, 1993), p. 236.
[3] O.R., Series I, vol. 32, pt. 3, p. 434.
 

wausaubob

Lt. Colonel
Joined
Apr 4, 2017
Location
Denver, CO
The initial Longstreet trip was to be THROUGH Knoxville, not stopping there. It was always the plan to have Longstreet fight with the AOT, not on its own.

The loss of the Knoxville route cost the South its best route from Atlanta to Richmond, but it cost only a handful of cars and engines (those captured in Knoxville). The surviving East Tennessee & Virginia RR rolling stock was taken up and operated by the Virginia & Tennessee RR; the East Tennessee & Georgia RR rolling stock was moved to a new company headquarters in Augusta, from which they were employed carrying freight (especially blockade runner cotton) into the Carolinas.
It seems like the Confederates were able to successfully withdraw from Corinth and save the locomotives and rolling stock. I don't think that was duplicated in Jackson, as Sherman seemed to have rotated around to the east of the town. The loss of equipment in the capture of Atlanta by the US forces seems to have been a severe blow to the Confederacy at that point in the war.
 

Rhea Cole

1st Lieutenant
Joined
Nov 2, 2019
Location
Murfreesboro, Tennessee
I don't understand your friend's math. An empty car sits in Atlanta, is loaded and sent to Richmond, unloaded, loaded with outgoing supplies to Atlanta. When the car arrives in Atlanta, it has made 2 trips, loaded both times. If there was no outgoing freight from Richmond (rare, but possible), there was still only a pair of trips involved -- Atlanta to Richmond and Richmond to Atlanta. I assume your friend is sending an empty car to Atlanta to start the trips, but empty cars to Atlanta were unheard of.

The direct route from Atlanta to Richmond was 760 miles; the route through central South Carolina was 700 miles. The eastern route was slower because of the change of gauge at Charlotte and the vastly increased number of freight inputs into the transportation flow -- Charleston, Wilmington, Petersburg, Columbia, Charlotte, Raleigh -- all traffic on the eastern route.
Here is a real world example. When we were sipping container loads to Britain, an empty container traveled from the Radnor yard in Nashville to our warehouse & back to Radnor, to To Manchester & another container had to come back to Radnor, etc. The availability of an empty container was absolutely vital. That is the three way nature of RR thinking.

The mountains of freight that was transported from Atlanta to Lee was one way. The Army of Northern Virginia had nothing that the Atlanta Depot needed. Empty rail cars were “deadheaded” back to Atlanta. A single load of freight required a boxcar to pass through Chattanooga three times.

I very often see a modern example of RR math in action. The Union Pacific & CSX run purpose built coal trains from Montana to a TVA coal plant on the south side of Monteagle Mountain. It is something to watch a lash-up of identical coal cars with an additional engine 2/3rds of the way back high balling southward. The same lash-up can be seen rolling north for another load. In RR terms, the 1,000 mile haul every load ties up equipment & track space for 3,000 miles.
 

Rhea Cole

1st Lieutenant
Joined
Nov 2, 2019
Location
Murfreesboro, Tennessee
I don't understand your friend's math. An empty car sits in Atlanta, is loaded and sent to Richmond, unloaded, loaded with outgoing supplies to Atlanta. When the car arrives in Atlanta, it has made 2 trips, loaded both times. If there was no outgoing freight from Richmond (rare, but possible), there was still only a pair of trips involved -- Atlanta to Richmond and Richmond to Atlanta. I assume your friend is sending an empty car to Atlanta to start the trips, but empty cars to Atlanta were unheard of.

The car, from the RR point of view, was not just sitting in Atlanta. The car was brought to Atlanta empty from Virginia. The prime contemporary example were the cars dedicated to the Augusta Armory. The cars & the reusable boxes were not available for any other use. Only one run delivered goods to Lee. It took two deadhead runs to make that system work.

The direct route from Atlanta to Richmond was 760 miles; the route through central South Carolina was 700 miles. The eastern route was slower because of the change of gauge at Charlotte and the vastly increased number of freight inputs into the transportation flow -- Charleston, Wilmington, Petersburg, Columbia, Charlotte, Raleigh -- all traffic on the eastern route.
 

Rhea Cole

1st Lieutenant
Joined
Nov 2, 2019
Location
Murfreesboro, Tennessee
During the beginning of the Atlanta Campaign, Sherman realized his dependence on the single-track railroad back to Chattanooga and Nashville. Sherman determined to stockpile supplies at field depots along the railroad to be prepared to move them to the troops by wagon train when necessary. Prior to the start of the campaign, it had been determined in a conference with his logistical team, that Sherman would need 130 railroad cars, each carrying 10 tons of supplies, arriving at Chattanooga each day to supply the army. This requirement took into effect expected losses by accident and raids, and even provided for a reduced amount of forage for the horses and mules (note that the calculations Sherman used were based on 100,000 men and 35,000 animals. His Quartermaster’s report for July 1, 1864 showed closer to 60,000 animals with the army and, if non-combatants were included, his army probably numbered closer to 125,000 men). Beef cattle and troop reinforcements would be forced to walk rather than take up space on the limited railroad cars. Despite howls of protest, Sherman also issued orders strictly limiting the railroad’s use to military and not civilian, requirements. Even then there were concerns that there was too little rolling stock and too few locomotives to meet the task. Prior to the start of the campaign, there were only about sixty serviceable locomotives and six hundred cars available. At least one hundred locomotives and one thousand cars would be required.[1] Revealing a quick temper and absolute impatience with those who obstructed or clung to the letter of regulations, Sherman is reported to have retorted to one such officer, “If you don’t have my army supplied, and keep it supplied, we’ll eat your mules up, sir – eat your mules up.”[2]

Before the end of April, Quartermaster General Montgomery C. Meigs had reported the accumulation of enough food at Nashville for 200,000 men for four months, and grain enough to feed 50,000 animals through the rest of the year. Also, rolling stock and locomotives were being built-up at the rate of fifteen new cars and one new engine per day.[3]



[1] Sherman, Memoirs, p. 467-469. George Edgar Turner, Victory Rode the Rails: The Strategic Place of the Railroads in the Civil War (Lincoln, NE, 1953), pp. 325-326. James A. Huston, The Sinews of War: Army Logistics 1775-1953 (Washington, D.C., 1997), p. 234-235. It should be noted that Louisville, Kentucky remained Sherman’s base for the entire campaign while Nashville and Chattanooga expanded into secondary bases. Other advance depots were located at Johnsonville and Knoxville, Tennessee and were involved in supporting Sherman’s drive on Atlanta.
[2] B.H. Liddell Hart, Sherman: Soldier, Realist, American (New York, 1993), p. 236.
[3] O.R., Series I, vol. 32, pt. 3, p. 434.
A train an hour left the Nashville yard on its way south 24/7. Engineers on the N&C RR were courageous men.
 

steamman

Private
Joined
May 26, 2020
Location
Columbus, Ga
I don't understand your friend's math. An empty car sits in Atlanta, is loaded and sent to Richmond, unloaded, loaded with outgoing supplies to Atlanta. When the car arrives in Atlanta, it has made 2 trips, loaded both times. If there was no outgoing freight from Richmond (rare, but possible), there was still only a pair of trips involved -- Atlanta to Richmond and Richmond to Atlanta. I assume your friend is sending an empty car to Atlanta to start the trips, but empty cars to Atlanta were unheard of.

The direct route from Atlanta to Richmond was 760 miles; the route through central South Carolina was 700 miles. The eastern route was slower because of the change of gauge at Charlotte and the vastly increased number of freight inputs into the transportation flow -- Charleston, Wilmington, Petersburg, Columbia, Charlotte, Raleigh -- all traffic on the eastern route.
I saw that and thought it was an odd way of looking at it. Based on the logic as I understand it, there would have been 3 way trips followed by one way trips.
 

Sgt. Tyree

Private
Joined
Apr 29, 2020
Location
Wyoming Territory
This is interesting. I know next to nothing about railroads, except that they were considered vitally important.

How important were freighters with supply wagons? I don’t mean as distribution from the RR yard to troops in the field, I mean for long range transport.

After all, armies were supplied for millennia before railroads, using everything from wagon trains to camel caravans. Were long range supply trains over roads simply impossible due to time and logistics?
 

Coonewah Creek

First Sergeant
Joined
Jun 1, 2018
Location
Northern Alabama
After all, armies were supplied for millennia before railroads, using everything from wagon trains to camel caravans. Were long range supply trains over roads simply impossible due to time and logistics?
Eventually you reach literally, the point of no return. When the supply distance is so long that you can't carry the additional grain for the draft animals in addition to your regular supply due to the distances involved.
 

DaveBrt

2nd Lieutenant
Joined
Mar 6, 2010
Location
Charlotte, NC
It seems like the Confederates were able to successfully withdraw from Corinth and save the locomotives and rolling stock. I don't think that was duplicated in Jackson, as Sherman seemed to have rotated around to the east of the town. The loss of equipment in the capture of Atlanta by the US forces seems to have been a severe blow to the Confederacy at that point in the war.
There was sever loss of rolling stock at Corinth when the army destroyed a bridge too soon.

I'm no aware of loss of rolling stock at Jackson. Could you provide a reference? Yes there was plenty of rolling stock isolated in northern and western Mississippi, but it was not known that they would stay isolated and, until the Union came down in raid after raid, they were useful in their area. Once Vicksburg was lost and it was clear that NW Mississippi could not be defended, there were efforts to remove that rolling stock.
 

DaveBrt

2nd Lieutenant
Joined
Mar 6, 2010
Location
Charlotte, NC
Here is a real world example. When we were sipping container loads to Britain, an empty container traveled from the Radnor yard in Nashville to our warehouse & back to Radnor, to To Manchester & another container had to come back to Radnor, etc. The availability of an empty container was absolutely vital. That is the three way nature of RR thinking.

The mountains of freight that was transported from Atlanta to Lee was one way. The Army of Northern Virginia had nothing that the Atlanta Depot needed. Empty rail cars were “deadheaded” back to Atlanta. A single load of freight required a boxcar to pass through Chattanooga three times.

I very often see a modern example of RR math in action. The Union Pacific & CSX run purpose built coal trains from Montana to a TVA coal plant on the south side of Monteagle Mountain. It is something to watch a lash-up of identical coal cars with an additional engine 2/3rds of the way back high balling southward. The same lash-up can be seen rolling north for another load. In RR terms, the 1,000 mile haul every load ties up equipment & track space for 3,000 miles.
Your real world example is for current conditions. The Confederacy had plenty to ship from Virginia to Georgia -- salt, artillery, rifle caps, lead, supplies that had been run through the blockade and stored in Richmond until called for, etc. Lee did not produce anything for Atlanta, but Richmond/Petersburg/Saltville/Lynchburg did. Empty cars were also used by the owning RR to pick up way freight, if they could get away with it under the eyes of the QM Department.

http://csa-railroads.com/Virginia_and_Tennessee_Tonnage,_Westward.htm
 
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