The key point?
Song Qing's mind raced, weighing his many past failures against this success.
None of the earlier steps had changed. The real difference had to be the final step: the lightning!
What set this strike apart from the last?
A faint arc of electricity flickered through his thoughts, and Song Qing stiffened. "I get it, I get it now," he said excitedly.
"Xu Ningyan, you really are an extraordinary alchemical genius."
"You never saw our failures, but you already knew, didn't you? You knew the real reason we kept failing."
No, I just know you're slowly turning into a tech-savvy nerd... Xu Qian smiled but said nothing.
"The key point? Senior Brother Song, what did you figure out?"
"Senior Brother Song, stop keeping us in suspense! Tell us! This alchemy is turning into a demon in my heart."
The white-robed alchemists pressed him impatiently, one after another.
Song Qing coughed, swept his gaze over his junior brothers, and said gravely, "It's the intensity of the lightning."
Then he looked to Xu Qian, seeking confirmation.
Xu Qian nodded with a smile and offered a hint: "I call it voltage."
To refine metallic sodium, the voltage had to be controlled between six and fifteen volts.
Voltage?!
Song Qing was taken aback. Another word he had never heard. He knew electricity, but what was voltage?
Instinctively he sensed this was remarkable knowledge, as profound as the essence of all things in that blue-covered book.
One alchemist stepped forward and bowed. "Please, sir, illuminate us. What is voltage?"
"Teach us," the others echoed, bowing in unison.
Chu Caiwei felt a pang of envy. She loved playing the master and instructing disciples, but as a mere Feng Shui Master she wasn't qualified to take pupils.
Voltage, also known as electric potential difference, measures the energy a unit charge gains between different potentials in an electrostatic field... Of course, none of that means a thing to you. Xu Qian cleared his throat and looked grave.
"Electricity is like water. It flows toward the lowest point."
He tipped out his teacup. "Spilling this on someone does no harm. But in a waterfall, a person beneath it would have bones shattered, even lose their life. Same with electricity. That phenomenon I call voltage."
White-robed men of the Directorate of Celestials furrowed their brows. Though alchemists who commanded thunder, they didn't grasp electricity's true nature.
Suddenly Song Qing understood something. "So that's it!" he said. "That's why lightning hits trees on rainy days, because the tree sits at a low point, and the same for people. If the current is faint, at most we feel numb. But endure a heavenly thunderbolt and we perish, body and soul."
"The thunderbolt's voltage exceeds what any mortal can bear, like a waterfall. A faint current is a cup of water, easy to withstand."
The alchemists saw the light, thrilled as though they'd uncovered a supreme truth, and turned expectantly to Xu Qian.
Hmm, is that really the principle? Isn't it the rain's conductivity that draws lightning to trees? My teacher never explained it clearly... Xu Qian himself wasn't sure, but he smiled. "A student worth teaching."
"Is this also in that alchemical manual?" a young man in white asked, hungry to know.
"Yes. Only I've read and studied it. What I sent the Directorate is a drop in the ocean." Xu Qian paused. "That ancient text holds knowledge and alchemical arts beyond anything you've heard of."
Their breathing thickened. Xu Qian threw out a promise that set them ablaze: "I've decided to share the manual with the Directorate of Celestials."
Whoosh! Nearly twenty alchemists erupted in excitement.
"That blue book I gave you was thanks for saving my life," Xu Qian said. "Guiding you to perfect forging counterfeit silver, and teaching voltage, wasn't free." He paused. "Nor will the manual that follows be."
"Never forget: alchemy's principle is equivalent exchange!"
Song Qing nodded, agreeing, and asked for his junior brothers, "How much silver do you want?"
"Crude!" Xu Qian said. "Alchemy isn't measured in silver."
The things you get free are always the most expensive... he added inwardly.
...
In the side hall of Changle County Yamen, Xu Lingyue cradled her slumbering little sister in her arms, dabbing at her tears with a handkerchief as she sobbed quietly.
At the sight of the tear-streaked beauty, the constables' hearts nearly broke. Who would have thought Xu Ningyan had such a delicate, lovely younger sister?
Even Warden Wang, who had visited the Bureau of Music, was dazzled by the young beauty.
The atmosphere in the side hall was heavy. The constables wore grim, drooping expressions.
Warden Wang poured a cup of tea and set it before Xu Lingyue. This young beauty had been weeping for a long while now, her tears never stopping. Women really were made of water.
"Miss Xu, don't fret. The Centurion will find a way to free Ningyan."
The other constables chimed in to comfort her, cursing Young Master Zhou freely.
My eldest brother gets along well with his colleagues... Xu Lingyue was a little surprised. The fierce indignation on the constables' faces did not look like pretence.
As if reading her astonishment, Warden Wang smiled. "Ningyan is a man worth respecting."
Respect? Xu Lingyue blinked, sniffled, and asked softly, "Warden Wang, could you tell me about my eldest brother?"
Warden Wang fell silent, then lowered his voice. "For men like us, whose hands are clean?"
"So long as we don't rob the common folk, that's a conscience. As for rich merchants, isn't skimming a little oil off them natural?"
"But your brother's different. Commoner or merchant, he never extorts anyone. A while back, knowing your family's troubles, I decided to take him along to skim a bit..." His expression turned strange, part embarrassment, part shame, part admiration. "He agreed with a grin. I gave him five taels as his cut, but he quietly returned the money."
"Call him worldly and he still ignores that water too clear has no fish. Call him naive and he's shrewd, getting along with everyone. He's slippery that way. So when he's in trouble, we all feel it."
Xu Lingyue listened, entranced. Her eldest brother's image grew taller, brighter, more towering by the moment.
She had idolized Xu Xinnian since childhood, because among all pursuits only study ranked high, and mother always told her her second brother was the family's only scholar, its future pillar.
That worship peaked last autumn, when he passed the provincial examination.
But then the tax silver case jailed the whole family, and in their despair her eldest brother carved out a path to survival.
Xu Lingyue turned her attention back to him, curious.
Only today did she see how reliable he was, just as he'd pulled them from prison a month ago. And back then the feeling surely wasn't as strong.
The moment she saw her brother save her sister, his image stood level with her second brother's.
And now, hearing Warden Wang's sighing praise, a figure of noble integrity, of principle and restraint, rose until it surpassed the brother she'd always admired.
Just then, the light at the side hall's entrance shifted, and Xu Pingzhi and his son finally returned to Changle County Yamen. Seeing their daughter and sister safe and sound, father and son sighed in relief.
Xu Lingyue lifted her head, her face streaked with tears, and cried miserably, "Father, you have to save eldest brother. If he can't come back, then I don't want to live either."