This week is “Chancellorsville Week.” So away with the Charleston stuff.
Major-General Joseph Hooker’s spring offensive called for quick movement of wide-ranging columns. Doesn’t take a stay at the War College to conclude such operations require solid communication links. Even the best general, commanding the best troops, cannot work effectively on a campaign of maneuver if orders move at the pace of a dispatch rider. In the 1860s, communication technologies being what they were, state of the art was the telegraph wire.
Given more space I would recount the lessons taught in the Army Signal School, even today, about techniques for laying field wire. The “physics” behind laying wire has not changed much in 150 years. Hooker’s “wire dogs” probably would find this illustration from a World War II manual familiar*:
So how good was Hooker’s telegraph network?
In his official report of the campaign, Captain Samuel T. Cushing, the acting Chief of Signal for the Army of the Potomac, provided a day-by-day accounting of the signal support during the campaign. I’ll focus on his remarks regarding telegraph wire support.
At the start of operations, on April 27, he received instructions to run telegraph lines to Bank’s Ford and Franklin’s Crossing. “Upon inquiring what rules should govern these lines, I was merely told to have them extended by night.” Cushing therefore did not extend the lines any further than explicitly ordered. No attempt was made to start wire runs along anticipated lines of advance. No attempt was made to stockpile wire where it might be needed.
The following day, Cushing received new orders to extend the line to United States Ford. In order to accomplish that run, he reused line recovered from the winter’s encampments. “I was obliged to use wire in which I had but little confidence, it having been in constant use for four months upon the line from general headquarters to Belle Plain.” Cushing complained that he requested to pull up that wire earlier, but was refused. So his troops pulled in 11 miles of wire, carried it to Bank’s Ford, then strung that wire back out to United States Ford, “making the aggregate distance marched by the party about 35 miles.” That’s 35 miles while placing wire. Cushing credits Captain F.E. Beardslee with the success of this operation.
But all for all the effort to run the line to United States Ford on April 28, no signals passed that evening. Cushing explained that, “owing to an accident to one of the instruments, communication was not opened that night. The wire was in bad order, and the instrument was not sufficiently strong to work through the wire with success.” I would guess this was due to kinks and bends in the recently recovered wire, which would add to attenuation of signal. Worse the wire, the stronger the power source needed. Not until 9 am on April 29 was the line working.
The woes continued on April 30. With a stronger set of batteries at Bank’s Ford, that telegraph station worked somewhat better. However, Cushing’s U.S. Military Telegraphers stood down when civilian operators arrived. “I was merely held responsible for the wire, subject partially to orders or instructions from the citizen operators.” Later that day, the wire was extended across the Rappahannock at United States Ford.
On May 1, Cushing received a detachment of eight officers, flagmen, and fifteen miles of wire. As the great battle was opening, Cushing was up in the air as to where that new wire would be best employed. Headquarters called for five miles of wire sent to Bank’s Ford. Cushing sent all fifteen.
With Federal headquarters at Chancellorsville on May 2, the signal troops completed the wire run to that point. While that was being done, an urgent request came to run wire to Brigadier-General John Gibbon’s headquarters in Falmouth. Not long after that line was run, Gibbon moved to cross the river. However, Cushing did establish a team to provide Major-General John Sedgwick’s headquarters with telegraph support when that Corps moved forward.
Now we all know that on the morning of May 3, Hooker was knocked unconscious by Confederate artillery fire. But at the same time the army commander was down, the communication infrastructure lapsed due to confusing orders. General Daniel Butterfield, Army Chief of Staff, ordered all units to stop using signals, complaining that the Confederates were reading them. “As all the important dispatches had heretofore been sent in cipher and as General Butterfield had been informed by me some days previous that we had a cipher in our possession, I do not understand why this order was sent. Suffice it to say that it had a most disastrous effect upon signal duty during the day.” This order effectively left the army communications at the speed of the dispatch rider during critical phases of the battle, and with elements engaged on separate fronts.
The signal team supporting Sedgwick placed wire across the Rappahannock and established a telegraph with his headquarters on the evening of May 3. Another team swam the river at Bank’s Ford and placed a telegraph station there. “This movement, though bold and daring, was of no immediate importance, and the instruments and wire were brought back in the evening.”
The communication woes continued through May 4. The signal flags, not the telegraph wires, were more useful communicating with Sedgwick. The “no signals” order remained in effect. Only late in the day did signal flag operators establish direct communications. (Allow me to save full discussion of the debilitating cipher problem for another post.)
On May 5 suffered, not from enemy action, but to the storm which blew threw. Cushing related that it “…greatly damaged the telegraph lines, tearing the poles down, and greatly deranging the instruments.” As the army retreated back across the Rappahannock on the following day, the signal troops recovered telegraph wire and equipment and fell back in turn.
Supporting an army on the move with wire-based communication – be that 1863 or today – requires good planning and mindful execution…. speaking from some experience with such matters myself.
(Cushing’s report is found in OR, Series I, Volume 25, Part I, Serial 39, pages 217-223.)
* However I would be remiss if I didn’t point out that most wire today is insulated, allowing for more installation options. Especially burying.