Readers’ Solutions
Readers of the Tactical Notebook offered four distinct solutions to the problem presented in Trading Places.
The first solution to the problem presented in Trading Places offered a three-step plan. The steps were:
A surprise attack against Bernberg in order to capture the bridge before the Prussians could detonate the charges placed upon it.
An attack across the Bode River in order to establish a bridgehead.
A defense of the bridgehead that exploits the superior range and power of the Saxon 12-pounder gun-howitzers to hold the position long enough to allow the deployment of main body north of the Bode.
The second solution involves an attack across the Saale, at or near Nienburg, in order to seize the town for use as a bridgehead. Once this is accomplished, a detachment from the advanced guard will explore the north bank of the Bode River west of Nienburg, in order to prevent the Prussian battalion in Bernberg from uniting with the Prussian forces in Calbe.
The third solution called for a crossing of the Saale between Bernberg and Nienburg. This exploited the presence of the Bode River between the Prussian force at Calbe and the crossing site.
In order to minimize Prussian interference with the crossing, the author of the third solution conducted two secondary operations. East of Calbe, he conducted a demonstration with artillery. East of Bernburg, he placed a battalion with the double mission of (1) fixing the enemy battalion in Bernburg and (2) exploiting any opportunity for crossing the Saale that might present itself.
The fourth solution also makes use of the superior firepower of the 12-pounders to fix the Prussian force in Calbe. In addition, it uses the route taken by the three infantry battalions to reinforce the impression that the Saxon forces are about to attack Calbe. These actions will reduce the chances that the larger Prussian force will interfere with the crossing of the Saale, which will take place between Nienburg and Calbe.
Once established on the west side of the Saale, the three battalions will have two options: (1) an attack to the south (across the Bode) in order to take Bernberg (and its bridge) from the west and (2) an attack to the north.
Moltke’s Solution
Trading Places replicates a problem that the recently-appointed head of the General Staff of the Prussian Army, Helmuth von Moltke, posed to his subordinates in 1858. The chief difference between the original problem and Trading Places lies in the description of the forces involved. While the original problem speaks only of a “Southern Corps” and the “Magdeburg garrison,” Trading Places identifies the first with the army of Saxony and the second with that of Prussia.
Trading Places provides this additional information because the officers engaging the original problem would have known three important facts that were not mentioned in the problem. The first was strained relationship between Prussia and Saxony, and, in particular, the desire of many Saxons to regain their lost territories. The second was the recent acquisition by the Saxon Army of a 12-pounder gun-howitzer [Granatkanone] that was much more powerful than the old-fashioned 6-pounder guns of Prussian field batteries. The third was presence of a Prussian garrison in the fortress of Magdeburg.
The original problem is the first of a collection of sixty-six tactical problems presented by Moltke between 1858 and 1882. Published by the Historical Division of the Great General Staff of the Prussian Army in 1892, this work also contains the solutions presented by Moltke at the conclusion of each exercise.
Moltke’s solution to the problem reads as follows:
The passage of a river like the lower Saale by means of constructing a bridge cannot be effected opposite a watchful enemy
either by day or night without his discovering and resisting it.
It must be forced.
The means to do so are the great strength of the attacking
force, which can remain concentrated while the defender must divide
and the greater effect of the 12-pounder battery. It is only a question of making that superiority felt at the proper point.
As soon as this principle is realized there is only the choice
left between Dröbel and Trabitz. At both places the passage can be
forced in the face of the enemy.
Against the former there is the difficulty of advancing further
beyond the steep slopes of the valley and across the Bode behind
which section of the ground the battalion from Bernburg will join
its main body from Calbe. 
At Trabitz we encounter at once the main force of the enemy
yet he is not able to prevent a crossing, and still less to prohibit the
further debouching of the united Southern Detachment. [The "Southern Detachment" is the advanced guard of the Saxon force.]
According to my opinion, Trabitz is therefore to be chosen, twelve
miles from Cöthen in the most direct line to Magdeburg. [Also called "Anhalt", Cöthen is the location of the main body of the Saxon army corps. It is located southeast of the southeast corner of the map.]
That point is reached with ease about midday.
The passage will be effected in two to three hours, after which the
attack upon the enemy takes place with united forces.
Since he does not find any tenable section of the ground, is
much weaker than we, and is threatened on his line of retreat, he
will only be able to try to gain so much time as is necessary to draw
in his battalion from Bernburg.
In addition to a small-scale map showing the area surrounding Bernburg and Calbe, the editors of the book of Moltke’s problems provided a large-scale map showing the peninsula at Trabitz. This makes clear the ability of the 12-pounder gun-howitzers to dominate the entrance to the peninsula and, in particular, to enfilade any Prussian force attempting to (1) move towards the crossing point at Trabitz or (2) fortify the base of the peninsula
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