He had gone to the White House on the morning after Lincoln had kept his appointment with the assassin. He had gone to perform the autopsy.

The letter described a room on the second floor, across the hall from Mrs. Lincoln’s bedroom: a bed, heavy draperies, a wardrobe, sofas occupied by military officers and civilian officials in stunned, grief-stricken silence … and the naked body of the president, covered with a sheet and towels, lying cold and dead on a board suspended between two sawhorses.

It was a letter of stark clinical detail. The doctor had been performing a primitive forensic analysis, after all. He described the removal and dissection of Lincoln’s brain and the search for the bullet, which he could not find until, “suddenly, it dropped through my fingers and fell, breaking the silence of the room with its clatter into an empty basin beneath. There it lay upon the white china, a little black mass no bigger than the end of my finger—dull, motionless, and harmless, yet the cause of such mighty changes in the world’s history as perhaps we may never realize.”

How true, thought Peter Fallon.

The man who fired that bullet, John Wilkes Booth, had heard Lincoln suggest four nights earlier that the nation’s renewal and reconstruction would mean extending the vote to some—but not all—Negro freedmen.

“That means nigger citizenship,” Booth had been heard to growl. “That is the last speech he will ever give. I will put him through.”

And so he had.

Since then, historians had sifted every Lincoln document and observation, searching for meanings and meanings within meanings. They had relived for one generation after another every moment of that terrible Easter weekend. And they had agreed with the young surgeon that the world had seen mighty changes, some because of what Lincoln had done, some because of what he had not lived to do.

So … was the history now settled?

How could it be, when an enigmatic letter might emerge a century and a half later, referencing a certain “something” that Lincoln wanted returned. What was it? What changes had it wrought? And how much, Peter had to wonder, would it be worth?

Time, he decided, for a whole weekend in Washington.

But before he packed, he texted Antoine Scarborough, his research assistant:

Abraham Lincoln, a lieutenant named Hutchinson in the telegraph office, a corporal named Jeremiah Murphy. That’s all I got. See what you can find. We’ll talk later.

TWO

April 1862

That night the Negroes sang.

They sang in the churches where they worshipped the white Jesus. They sang in the hammer-nail hovels where they lived. They even sang on Pennsylvania Avenue, where Uncle Abe might hear them in his fancy white house.

From the second-floor windows of the War Department telegraph office, Lieutenant Halsey Hutchinson watched them go by.

They were singing spirituals and minstrel songs and marching songs, too, songs that climbed Jacob’s ladder and raised a ruckus and blessed John Brown, whose body by then had been three years a-molderin’ in the grave, but whose truth was surely marching on through that warm spring night, because Congress had passed an emancipation act for the District of Columbia. And after five days of rumination, the president had signed the bill, freeing three thousand slaves with the stroke of a pen … and the promise of restitution to the District slave owners.

So the Negroes sang.

Halsey Hutchinson did not much care about them. He had joined the army to preserve the Union. But he could not blame them for celebrating.

He even hummed a bit of “John Brown’s Body” himself. It was a tune with a stir to it. It made a man want to march. It made him want to sing out from deep in his chest. It had even inspired a Massachusetts lady to write new lyrics that she called a battle hymn. Halsey had read the lyrics in the Atlantic Monthly, but he had not yet committed them to memory. It would not have mattered, because he could not sing … anymore.

A year earlier, when he gathered with his wine-punching friends in Boston clubs or performed for adoring females in fancy parlors, he could give out with the voice of a baritone angel. And no lieutenant had ever offered a sweeter hymn at Camp Massasoit, where the Twentieth Massachusetts Volunteer Infantry had mustered and trained and worshipped through six weeks of summer Sabbaths. And during those long autumn nights of tenting on the Potomac, his songs had made the waiting easier for any who heard him … Billy Yank or Johnny Reb across the river.

Now it was a wonder that he could even talk.

A rebel bullet had struck him in the throat, leaving his voice a graveled whisper, perfectly distinct but no longer loud enough to be heard by men in the midst of battle.

That same bullet had also damaged his resolve. One moment he had been rallying his men at the base of a promontory called Ball’s Bluff, the next he was sprawled in the mud with blood gushing from a wound at his collar. By the grace of God, it had been a glancing wound, but a wound nonetheless, as if someone had struck him in the neck with a ball-peen hammer.

He still believed in the sanctity of the Union. But after Ball’s Bluff, he had begun to wonder if the Lord believed otherwise.