Railroad Math, Why Chattanooga Mattered

wausaubob

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Not only did Chattanooga matter, but getting there by the operation designed by Rosecrans and Thomas was the right way to re-establish federal control. The north to south line from Louisville to Chattanooga was much easier to defend against Confederate raiders.
And the line began in Louisville which was attached to the US economy by railroad and by the Ohio River. The starting point was a federal city that was making money during the war.
 

Coonewah Creek

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Northern Alabama
These discussions are very interesting from a mathematical optimization problem. As a matter of fact, there's a whole branch of linear programming optimization mathematics that deals with transportation system and supply chain optimization. Would have been helpful if the Confederates had had computers and software to take advantage of it, sounds like!
 

Rhea Cole

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Murfreesboro, Tennessee
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?
What a good question. Until the Civil War, armies moved at the same rate as Roman Legions. The thousands of miles of paved road allowed Rome to move troops & supplies with unprecedented ease. That was as good as it got until the 1850’s when the US RR system came into existence.

When Lincoln & Stanton learned of Rosecras’ setback at Chickamauga, they immediately issued orders for two corps from the A of the P southward. Within 24 hours, troop trains were rolling along the 1,100 miles to the Tennessee River.
Not only were two corps transported, the supplies necessary for keeping them in fighting trim rolled out of the Nashville depot. A train an hour 24/7 left Nashville headed south & passed trains headed northward on the single track Nashville & Chattanooga RR.

As I write this, I can hear the sound of trains signaling as one waits on the siding for the other to pass. The CSX mainline between Nashville & Alabama is still a single track because of the 2,200 foot tunnel through Monteagle Mountain. That is exactly what was happening during the Civil War.

Depending on whether it was loaded with bacon or beef/pork in barrels, a rail car was loaded with 8-9,000 daily rations. A single ten car lash-up could deliver one day’s ration for Rosecrans’ army. No logistical system in history came close to that efficiency.

Where the RR totally revolutionized logistics is something that modern people never think about. A horse required 26 pounds of feed/day. All you have to do is multiply the 125 horses of an artillery battery by a week or a month to get dome idea of the challenge feeding them involved. A round bale weighs 1,000 pounds & is a good way to conceptualize.

CW fodder was shipped in gunny sacks. The return of the empty sacks was absolutely essential. Historically, armies had to keep on the move in order to feed their horses. Even Henry VIII had to move from palace to palace because no locality could support his retainers & their horses for more then a few weeks at a time. During the Tullahoma Campaign, Rosecrans ordered the RR to transport fodder southward, broken down animals northward. Rations & ammunition were transported by wagon. It was the RR that made the 100 mile advance from Murfreesboro to Chattanooga possible. It was the N&CRR that made it possible to stay & build up for the Atlanta Campaign.

The Civil War was the first RR war. As in so many things, it was the harbinger of things to come.

Hope this answers your question. CW railroading is a fascinating topic. Dig in & enjoy.
 
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wausaubob

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When the 1860 census data was reworked and published in 1866, it turned out that Louisville was the 12 city on the list.
Since New York, Brooklyn and Newark were one vast metro area, Louisville was actually the 10th largest metro area. And with New Albany, IN connecting it to the US economy, it was even more important.
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https://www2.census.gov/library/publications/decennial/1860/statistics/1860d-01.pdf p. xviii.
 

Rhea Cole

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That would apply to a one-time trip, or the first trip on what is intended to become a regular route. In the latter case, once a car is brought into rotation, it makes two trips per delivery.

When positioning cars to start service, the railroad will try to find cars near where they are needed to minimize the non-productive time. For example, if you need cars to run from Atlanta to Richmond, hopefully you would find them someplace not too far away, like Montgomery or Augusta. The positioning trip would be shorter than the delivery or return trip. In terms of distance or time, "3 trips" might be more like "2.3 trips".
Of course, the intricate, complex & high stakes details of managing a freight line far exceed my deliberately simplistic example.
 

wausaubob

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The line from Louisville/Bowling Green/Nashville/Murfreesboro/Chattanooga was the correct line. It was anchored in Louisville and most of it was too far north to be vulnerable. But Rosecrans had a tremendous struggle to get Halleck to recognize that the Memphis/Chattanooga connection was not valuable. And Rosecrans similarly could not convince the War Department that the money had to spent to bring the line up to 1st class, eastern standards, as much as possible. This argument ended when Miegs and McCallum came west and Stanton cut Halleck out of his communication with Grant.
 

wausaubob

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And what was done differently once the USMRR took over? The non perishable railroad supplies, the ties, rails, switches, hardware and tools were forwarded and stockpiled so that each town could repair its segments quickly. These supplies did not spoil. The second priority was the feed and forage for the livestock. Normally the oats could be bagged and the hay stacked. If they were covered, they did not spoil. Forwarding the supplies for the army, the weapons, powder, food and clothing, did not make sense. If the RR was kept open, and the new locomotives kept arriving, those types of supplies could be freighted on an as needed basis.
 

Rhea Cole

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Murfreesboro, Tennessee
Interconnected systems were less vulnerable to capture and to sabatoge. There were alternative routes if one went down.
You have made an excellent point. I did not want to complicate the examples , but because the Southern RR’s were deliberately not interconnected, freight & troops had to be unloaded on one side of town. & reloaded on the other... like a portage past a rapid. One of the first orders of business after Nashville was captured was connecting the L &N-N&CRR tracks together & with other lines terminating there.
 

wausaubob

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You have made an excellent point. I did not want to complicate the examples , but because the Southern RR’s were deliberately not interconnected, freight & troops had to be unloaded on one side of town. & reloaded on the other... like a portage past a rapid. One of the first orders of business after Nashville was captured was connecting the L &N-N&CRR tracks together & with other lines terminating there.
It was about 1860 when the railroads realized their interests were diverging from the towns they connected to. The towns wanted the freight and passengers to have to stop and reload. That was good for them. The railroads began to realize that faster and more efficient service meant more revenue for everyone. The advent of the Pullman car was approaching.
 

Carronade

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But Rosecrans had a tremendous struggle to get Halleck to recognize that the Memphis/Chattanooga connection was not valuable.

Curious about this - why would anyone think of supplying Chattanooga via Memphis? Memphis could only serve as a supply base for the Union if materials were shipped there - mainly from the Midwest.

Initially of course they had to move troops and probably some material from the Mississippi valley to Chattanooga, but once that was done, it's hard to see the value of the connection.
 

wausaubob

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Curious about this - why would anyone think of supplying Chattanooga via Memphis? Memphis could only serve as a supply base for the Union if materials were shipped there - mainly from the Midwest.

Initially of course they had to move troops and probably some material from the Mississippi valley to Chattanooga, but once that was done, it's hard to see the value of the connection.
The 1st explanation is always stupidity, but in the case of Memphis, corruption cannot be ruled out either.
 

wausaubob

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There is a remarkable difference between 1862 when Buell was operating the system and 1863 when Rosecrans took control. The pressure to advance in the former year finally succeeded in the ability to utilize the system more efficiently. The time management shown in the latter year was a big improvement.
Lubliner.
But I think Rosecrans' method was abandoned. The correct method was to use the slack periods to stockpile durable goods. Hay and oats did not spoil as fast as powder and human food, so those things too could be forwarded if there were barns and warehouses. The army's consumables should be shipped on an as needed basis. All civilian traffic had to be barred during the critical months of the campaign.
 

Rhea Cole

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Murfreesboro, Tennessee
But I think Rosecrans' method was abandoned. The correct method was to use the slack periods to stockpile durable goods. Hay and oats did not spoil as fast as powder and human food, so those things too could be forwarded if there were barns and warehouses. The army's consumables should be shipped on an as needed basis. All civilian traffic had to be barred during the critical months of the campaign.
I have studied this in detail. I conducted a staff ride for logicians from FT Campbell of Fortress Rosecrans a couple of years ago. I learned a lot that I did not know about the realities of CW supply. A single boxcar carried 8-9,000 daily rations, 10,000 marching rations. Fodder, at 26 pounds a day, was extremely bulky.

The sheer volume, not tonnage, of fodder that had to be shipped to Rosecrans’ army runs to multimillions of cubic yards. It was consumed at a steady pace, unlike ammunition. Fodder was shipped from as far away as northern Illinois & Ohio. Ten boxcars could deliver a day’s ration to the men of Rosecrans’ army.
Do to it’s cubic bulk, it took 100+ carloads to feed the animals. A soldier’s ration weighed about 3 pounds, a horse’s ration 26 pounds... you can do the math. A ten car train an hour was dispatched from the Nashville Depot, you can imagine how many of them was hauling fodder.

One fact that I came on really opened my eyes. During the 1914-1918 war, England shipped more tonnes of long fodder than they did ammunition.

To illustrate to the Army logicians the scale of Rosecrans’ army, I showed them that if the lead elements had arrived at Murfreesboro with them, the tail end Charlie would have been leaving the gate at FT Campbell.
 

wausaubob

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Denver, CO
I have studied this in detail. I conducted a staff ride for logicians from FT Campbell of Fortress Rosecrans a couple of years ago. I learned a lot that I did not know about the realities of CW supply. A single boxcar carried 8-9,000 daily rations, 10,000 marching rations. Fodder, at 26 pounds a day, was extremely bulky.

The sheer volume, not tonnage, of fodder that had to be shipped to Rosecrans’ army runs to multimillions of cubic yards. It was consumed at a steady pace, unlike ammunition. Fodder was shipped from as far away as northern Illinois & Ohio. Ten boxcars could deliver a day’s ration to the men of Rosecrans’ army.
Do to it’s cubic bulk, it took 100+ carloads to feed the animals. A soldier’s ration weighed about 3 pounds, a horse’s ration 26 pounds... you can do the math. A ten car train an hour was dispatched from the Nashville Depot, you can imagine how many of them was hauling fodder.

One fact that I came on really opened my eyes. During the 1914-1918 war, England shipped more tonnes of long fodder than they did ammunition.

To illustrate to the Army logicians the scale of Rosecrans’ army, I showed them that if the lead elements had arrived at Murfreesboro with them, the tail end Charlie would have been leaving the gate at FT Campbell.
We are essentially in agreement. A systems engineer would see Rosecrans method as responsive to conditions in which the railroad was not in good shape, did not have enough equipment and was subject to Holly Springs type raids. Under those conditions the depots especially of fodder have to be moved forward as much as possible.
But once the US dedicates enough civilian manpower to keep the road operational, and enough military manpower to protect all the bridges and depots, interruptions are something that can be dealt with. Than everything can shift toward as needed movements and extra trains to move the stockpiles are not necessary.
 

Coonewah Creek

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Northern Alabama
But once the US dedicates enough civilian manpower to keep the road operational, and enough military manpower to protect all the bridges and depots, interruptions are something that can be dealt with. Than everything can shift toward as needed movements and extra trains to move the stockpiles are not necessary.
Your statement can be illustrated by Sherman's campaign against Atlanta. Sherman was aware of the vulnerabilities of the rail system that supplied his army and remembered only too clearly the devastating one-two punch delivered by Forrest and Van Dorn against Grant’s West Tennessee railroad supply network and advance depot at Holly Springs, Mississippi during the first drive against Vicksburg in December 1862. He knew that it only took one destroyed bridge, tunnel, or trestle to disrupt the critical flow of provisions and ordnance for his troops. To prevent this type of disaster, he ordered that blockhouses with a garrison of at least twenty men each be constructed at both ends of all critical bridges along the railroad. This gave some advantage to the defenders, at least against a small cavalry or guerrilla force, which Sherman hoped would act as a deterrent to such attacks. Sherman also obtained the services of Colonel W.W. Wright for his engineering tasks, bridge construction and repair. Wright worked under Sherman’s rear area headquarters to consolidate these matters under one central authority for the Division of the Mississippi. This was one of the real secrets of Sherman’s success. Damage to tracks and other railroad facilities were rapidly repaired by detachments of the Construction Corps, which were stationed at critical points along the railroad. Stockpiles of rails, ties, and timbers were ready to move out on short notice to repair damaged track.https://civilwartalk.com/#_edn1 With the mention of Colonel Wright, it should be noted that three Federal officers rarely mentioned in the story of Sherman’s Atlanta Campaign are Colonels Daniel C. McCallum, Adna Anderson, and William W. Wright. This trio was charged by Sherman with creating, operating, and maintaining his railroad lifeline with the rear. In his memoirs Sherman wrote, “The Atlanta campaign would simply have not been possible without the use of the railroads.” These three colonels were responsible for making the campaign possible. McCallum was director and general manager of military railroads. Anderson headed the Department of Transportation, which operated the supply trains, and Wright, as previously mentioned, commanded the Department of Construction, which kept roadbed, track, and bridges operational. In addition to these three men, a civilian superintendent of bridge construction, E.C. Smeed, performed truly remarkable feats in quickly bridging the Etowah and Chattahoochee rivers, helping ensure that at no time were the trains coming down the Western & Atlantic Railroad more than five days behind Sherman’s army.[ii]

Out of almost 180,000 troops reported present for duty in the three Federal armies under his command, Sherman determined that a large number would be needed for garrison duty and for protection of the army’s line of communications during its drive south. The Union railroads ran for some three hundred miles across Kentucky and Tennessee. In addition to the detachments from his main army group, the Federals also mobilized several thousand Midwestern militiamen for three months service to help garrison the railroads. The seasoned troops were typically employed south of Chattanooga, amounting to an average of about 230 men per mile of track. Eventually Sherman assigned General James B. Steedman to command the District of the Etowah, an organization whose sole purpose was railroad defense.[iii] The Federal commander therefore began the campaign in May with some 98,797 men and 254 pieces of artillery in his mobile field force. He would endeavor to maintain a reserve of twenty days’ rations with the army as insurance against supply interruptions.


https://civilwartalk.com/#_ednref1 Huston, The Sinews of War, p. 235.
[ii] Cooke, “Feeding Sherman’s Army,” p. 89. McDonough and Jones, War So Terrible, p. 34. O.R., Series I, vol. 32, pt. 2, pp. 329, 365, 372. Huston, The Sinews of War, p. 235.
[iii] McDonough and Jones, War So Terrible, pp. 35-36.
 

Rhea Cole

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Nov 2, 2019
Location
Murfreesboro, Tennessee
We are essentially in agreement. A systems engineer would see Rosecrans method as responsive to conditions in which the railroad was not in good shape, did not have enough equipment and was subject to Holly Springs type raids. Under those conditions the depots especially of fodder have to be moved forward as much as possible.
But once the US dedicates enough civilian manpower to keep the road operational, and enough military manpower to protect all the bridges and depots, interruptions are something that can be dealt with. Than everything can shift toward as needed movements and extra trains to move the stockpiles are not necessary.
Of course, a boxcar of rations is useless if they are not distributed effectively. That is one of Grant’s strengths that logicians admire. A horse can only travel 20 miles a day & stay sound. Once broken down, rehab was both problematic &.time consuming. The volume of broken down stock coming north on the N&CRR was astonishing to me when I began my dive into logistics.

Grant was very careful to establish rail & river terminals no more than ten miles from distribution points. Ten miles out & ten miles back kept the animals healthy & the supplies moving. Once again, it is that three legged way of managing transportation assets.
 
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