Clockwork Princess

sequence of numbers that are printed at the bottom of this letter, are spoken to my automaton, I am sure to receive it
.
    Yours sincerely
,
    Axel Mortmain
    “That is all,” Charlotte said, folding the letter in half and placing it back on the salver. “There are instructions on how to summon the automaton to which he wishes us to give our answer, and there are the number he speaks of, but they give no clue as to his location.”
    There was a shocked silence. Cecily, who had seated herself in a small flowered armchair, glanced at Will and saw him look away quickly as if to hide his expression. Jem paled, his face turning the color of old ash, and Tessa—Tessa sat very still, the light from the fire chasing shadows across her face.
    “Mortmain wants
me
,” she said finally, breaking the silence. “In exchange for Jem’s
yin fen
.”
    “It is ridiculous,” Jem said. “Untenable. The letter should be given to the Clave to see if they can discern anything about his location from it, but that is all.”
    “They will not be able to discern anything about his location from it,” said Will quietly. “The Magister has proved himself over and over too clever for that.”
    “This is not clever,” said Jem. “This is the crudest form of blackmail—”
    “I do not disagree,” said Will. “I say we take the packet as a blessing, a handful more of
yin fen
that will help you, and we ignore the rest.”
    “Mortmain wrote the letter about me,” Tessa said, interrupting them both. “The decision should be mine.” She angled her body toward Charlotte. “I will go.”
    There was another dead silence. Charlotte looked ashen; Cecily could feel her own hands slippery with sweat where they twisted in her lap. The Lightwood brothers seemed desperately uncomfortable. Gabriel looked as if he wished he were anywhere else but there. Cecily could hardly blame them. The tension between Will, Jem, and Tessa felt like a powder keg that needed only a match to blow it to kingdom come.
    “No,” Jem said finally, rising to his feet. “Tessa, you cannot.”
    She followed his motion, rising as well. “I can. You are my fiancé. I cannot allow you to die when I might help you, and Mortmain does not mean me physical harm—”
    “We do not know what he means! He cannot be trusted!” Will said suddenly, and then he put his head down, his hand gripping the mantel so hard that his fingers were white. Cecily could tell he was forcing himself to be silent.
    “If it were you Mortmain wanted, Will, you would go,” said Tessa, looking at Cecily’s brother with a meaning in her eyes that brooked no contradiction. Will flinched at her words.
    “No,” said Jem. “I would forbid him as well.”
    Tessa turned to Jem with the first expression of anger toward him Cecily had ever seen on her face. “You cannot forbid me—any more than you could Will—”
    “I can,” Jem said. “For a very simple reason. The drug is not a
cure
, Tessa. It only extends my living. I will not allow you to throw away your own life for a remnant of mine. If you go to Mortmain, it will be for nothing. I still won’t take the drug.”
    Will lifted his head. “James—”
    But Tessa and Jem were staring at each other, eyes locked. “You would not,” Tessa breathed. “You would not insult me by hurling a sacrifice I made for you back in my face like that.”
    Jem strode across the room and seized the packet—and the letter—off Charlotte’s desk. “I would rather insult you than lose you,” he said, and before any of them could make a move to stop him, he cast both items into the fire.
    The room erupted in shouts. Henry dashed forward, but Will had already dropped to his knees before the grate and thrust both his hands into the flames.
    Cecily bolted out of her chair.
“Will!”
she shouted, and darted over to her brother. She seized him by the shoulders of his jacket and pulled him away from the fire. He tumbled backward, the still-burning packet falling from his hands. Gideon was there a moment later, stamping out the small flames with his feet, leaving a mess of burned paper and silvery powder on the rug.
    Cecily stared into the grate. The letter with the instructions telling how to summon Mortmain’s automaton was gone, burned into ashes.
    “Will,” Jem said. He looked sick. He fell to his knees next to Cecily, still holding her brother’s shoulders, and drew a stele from his jacket. Will’s hands were scarlet, livid white where blisters