Tuesday, June 18, 2013

Spies and Lies: Tricks of the Trade in the Civil War by Tom Rizzo

The Union spy blinked a few times to clear his eyes of drifting candle smoke, and removed the toothpick soaking in a shallow bowl of lemon juice. Satisfied it was saturated enough, he began scratching an invisible message into the vellum paper on the table in front of him, taking care to keep it away from the flame. 

Minutes later, he exhaled, relieved to be finished. He snapped the toothpick in half and dropped the two pieces inside one of his boots. The fingers of his right hand ached from having to write so deliberately, and wiggled them open and closed a few times. He stared at the paper, squinted, and shrugged, not knowing whether the secret communique' was even legible. 

One of his colleagues had described the plodding activity as "writing in the blind." The message could only be displayed when the recipient held it in front of a candle flame.  

Messages written in invisible ink — by both the North and the South — provided key information to military commanders, including: locations of regiments, artillery batteries, prisoners and supplies.

The shorter the message, the better. Simple trumped complex.

Creating messages with lemon-juice, and other invisible ink techniques, were effective, but couldn't be used with much success in communicating more complex information, such as detailed battle plans.

Invisible writing, however, was among the chief techniques spies on both sides used to convey coded messages. But savvy code-breakers were usually able to decipher the messages, which often revealed the location or tactics of an enemy army.

Spying played a key role in the American Civil War for both sides, and in different ways.

MilkElizabeth Van Lew,  a spy for the Federals, for example, wrote her messages in a special ink that would only be revealed when milk was applied to them.

Confederate spy Rose O'Neal Greenhow  wouldn't allow her own arrest and imprisonment deter her undercover efforts. In fact, she managed to devise encoded  messages in letters to fellow spies in a most ingenious way.

Knowing that her letters would be scrutinized, Greenhow commandeered a bottle of invisible ink solution. But, rather than use it, she placed the bottle where she knew Union authorities would discover it. And, they did. As a result, detectives wasted valuable time checking her letters for invisible ink rather than deciphering the hidden messages in her supposedly innocent correspondence.

For some operatives, the work was fairly routine, and involved debriefing runaway slaves, deserters and others.

The telegraph played a key role in spy activity.

TelegraphWhen Union agents managed to tap into the Confederate telegraph line between Chattanooga and Knoxville, for example, they intercepted mail but, at the same time, transmitted phony messages to confuse the enemy even further.

At one point, Confederate Commander Robert E. Lee expressed nothing but distrust for the telegraph, and once prohibited his officers from using the device.

Union Commander Ulysses S. Grant, on the other hand, used the military telegraph to implement key tactics and important strategy. From his headquarters, Grant issued daily orders by telegraph and received reports regarding the operations and movement of the various armies under his command. Grant was able to utilize the telegraph to maintain direct control over half a million soldiers, stretched across a territory of 800,000 square miles.

"The value of the telegraph cannot be exaggerated, as illustrated by the perfect accord of action of the armies of Virginia and Georgia," said General William T. Sherman.

Both North and South engaged in a broad variety of spying activity to unearth vital military intelligence.

A variety of spying techniques was put into play to gain the upper hand, knowing that one, vital piece of information that could make the difference between victory and defeat.

In addition to a vast network of relatively inexperienced intelligence agents, both armies tried new tactics.
New technology, such as photography, came into play. Soliders of either army were always willing to pose for photographs, which were studied for information on the terrain and location of an enemy army.

Both sides took to the air with hot-air or hydrogen-filled balloons for spy missions.

Thaddeus Lowe Balloon On September 24, 1862, Union spy Thaddeus Lowe rose to more than 1,000 feet where he spotted movement by Confederate troops. He transmitted his discovery to Union  soldiers on the ground who began firing on the Rebels.

During the Battle of Fiar Oaks, Lowe issued hourly transmissions on Confederate troop movements. The information ranked as a key factor in the Union's victory.
In 1862, the Confederate spies went aloft in hot air balloons so they could sketch the Union's positions in Yorktown, Virginia.

While aloft, balloonists used telegraph or signal flags to transmit the information they gathered. Some Union Army balloons were sizable enough to accommodate telegraphers and their gear so there would be no delay in relaying their observations to officers on the ground.

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  1. Thanks for the info, Tom. I've read a little about the hot air balloons--would love to learn more about it and whether they were ever used in the Indian Wars.

  2. Hi Jacquie-I wondered about the use of balloons after the Civil War, but the only reference I found was something about them being used for observation during WW1.

  3. An excellent post, Tom. I love the use of misdirection by Rose O'Neal Greenhow. That was so clever.


  4. Keith--Yes, she sounds so cool and collect under pressure, and creative too. To think out that misdirection while she was in prison just adds to her legacy.

  5. Greatinformation, Tom, thanks. But you missed those most effective Union spies, the Three Stooges- aka Lt. Duck, Capt. Dodge, and Major Hyde...

  6. Troy--You're right. I should have paid more attention those Uncivil Warriors who cleverly deluded Confederate Gen. Butts,

  7. Tom, Rose O'Neal Greenhow seems like a very calm woman who knew exactly how to make her captors follow the wrong trail with ease. Such great deception, to put the idea in their heads like that!I truly loved this post of yours. I have a book about Civil War spies that I bought on sale at B&N but have not had a chance to read yet. GREAT POST!

  8. Cheryl-glad you liked it. When you finish the books about spies, let me know how you liked it.

  9. Fascinating..Rose was not only courageous, she was brilliant.
    The idea of the hot air balloons was new to me...I knew about the invisible ink idea, but didn't know the ingredients.
    Any author who might write a Civil War novel could sure use this information.

  10. Yes, Celia. She obviously had a quick mind. We can test the theory of invisible ink in this post.

    Si p y h ld this u to the f ame of a c nd e to s e if i s le i ble .

  11. What an interesting post, Tom. I loved all the spy techniques. I never knew they used hot air balloons as a method to spy. I guess they were too high in the air to be shot down. There certainly were some innovative and intelligent spies in those days.
    Great article.

  12. Thanks, Sarah. You're probably right about those balloons behing out of range.

    And, I agree, the spies were certainly innovative and savvy, especially so since neither side had very effect spy programs at the beginning of the war.

  13. Five Union POWs hijack a hot air balloon to escape the Rebs, then get stranded on the MYSTERIOUS ISLAND, Jules Verne's sequel (of sorts) to 20,000 LEAGUES UNDER THE SEA...

  14. I have not read MYSTERIOUS ISLAND, but I understand those five balloon hijackers had a dog in tow, as well.

  15. Tom, that invisible ink thing was very interesting. I'm going to go get a lemon and try it!

  16. MYSTERIOUS ISLAND could be re-named FINDING NEMO...

  17. Fascinating and informative. Thank you. Doris

  18. Hi Tom,

    Rose O'Neal Greenhow was quite a clever gal, wasn't she? Bet she had a good chuckle.:)

    I didn't know they used hot air balloons for spying. Fascinating info. Thanks so much for sharing.

    I do enjoy your posts. You always have interesting information.

  19. Doris--Thanks for the comments. Yes, Rose O'Neal Greenhow was indeed clever. In fact, after she was "deported" to Baltimore, Jefferson Davis sent her to Britian and France to drum up support for the Confederacy. Actually, hundreds of women served as spies in the war.

    Karen Michelle--Most of the hot air balloons were powered by hydrogen gas, which provided more lift. And, among several problems encountered, the most serious was that these manned balloons were pretty much defenseless.