“My eyes have been hurting,” I say, while we are still pushing the metal into place, so that he cannot ask me to assist him. “They feel like sand has gotten into them.”

“I have a patient with a disease I do not recognize,” he says. I am relieved, though disease can kill us as easily as a trench mortar. Soldiers die of pneumonia and dysentery and blood poisoning every day in the dressing station, but we do not fear it the way we fear the front.

“The patient has fever, excoriated lesions, and suppurating bullae,” Dr. Funkenheld says.

“Could it be boils?” I say, though of course he would recognize something so simple as boils, but he is not listening to me, and I realize that it is not a diagnosis from me that he has come for.

“The man is a scientist, a Jew named Schwarzschild, attached to the artillery,” he says, and because the artillery are even farther back from the front lines than we are, I volunteer to go and look at the patient, but he does not want that either.

“I must talk to the medical headquarters in Bialystok,” he says.

“Our wireless is broken,” I say, because I do not want to have to tell him why it is impossible for me to send a message for him. We are allowed to send only military messages, and they must be sent in code, tapped out on the telegraph key. It would take hours to send his message, even if it were possible. I hold up the dangling wire. “At any rate, you must clear it with the commandant,” but he is already writing out the name and address on a piece of paper, as if this were a telegraph office.

“You can send the message when you get the wireless fixed. I have written out the symptoms.”

I put the back on the wireless. Müller comes in, kicking the door open, and snow flies everywhere, picking up Dr. Funkenheld’s message and sending it circling around the dugout. I catch it before it spirals into the flame of the Primus stove.