The Chemickal Marriage

Hanging from the knob by a leather loop was a notched brass tube three inches long.
    ‘The pneumatic vestibule,’ Svenson said. ‘And here is the key.’
    Inside the panelled box, Svenson paused. ‘Do we follow the Contessa, or escape?’
    ‘She may have returned to the attic, to Francesca,’ said Miss Temple.
    ‘We don’t know that the child is there,’ Chang cautioned. ‘I say we descend to where we entered and hope it is not thronged with soldiers.’
    Acknowledging this logic, Svenson thrust the key into the slot and stabbed the lowest button on the brass plate. The car vibrated with life. They descended without speaking – all three with weapons ready – but when they heard the tell-tale
clank
the car did not stop.
    ‘I thought we entered directly below the cellars,’ said Chang.
    ‘Perhaps we did not pay attention,’ said Miss Temple. ‘Perhaps it was two stops below.’
    ‘It wasn’t.’
    ‘Then there is another floor further below.’
    A second
clank
and the car came to a halt. Chang pulled the iron gate open and set his shoulder against the tarnished metal door beyond it.
    This was not the underpassage to Stäelmaere House. Instead, they had been delivered to another tunnel, with a tiled floor like a bath house. A single lantern, lit within the hour judging by the level of oil, had been left on the floor. Next to it, like a malicious rose, lay a third red envelope.
    It was empty save for a scrap of white tissue, smeared with a scarlet imprint of the Contessa’s mouth. Svenson said nothing. Chang scowled with displeasure. Miss Temple put her nose to the tissue, and observed that it smelt of frangipani flowers. They began to walk.
    ‘This cannot have been simple to construct,’ said Svenson. ‘The digging must have displaced the coach traffic above us for ages –’
    ‘Nothing of the kind has displaced anything,’ called Chang, walking in the lead. ‘This can only be the old Norwalk.’
    This meant nothing to Svenson or Miss Temple. Chang sighed. ‘The Norwalk fortifications were dismantled to lay the Seventh Bridge, and the new Customs House.’
    ‘I have been to the Customs House,’ said Miss Temple. ‘To learn about trade.’
    ‘That does you credit,’ said Svenson. ‘It is the rare heiress not simply content to spend.’
    Miss Temple made a bothered face. ‘I did not want to be cheated – sugar-men are famous scoundrels. But, once I was inside, tiresome is not the half of it –’
    Chang cleared his throat. They stopped talking. He went on.
    ‘The Norwalk formed one wall of the original Citadel. I would guess this was once a lower catacomb.’
    ‘But why has it been remade?’ asked Svenson. ‘New tile and fresh paint.’
    Chang reached into his coat for his razor. With the handle he scratched a line in the plaster and blew the dust away. ‘Replastered these past two months.’
    ‘Before or after the dirigible went into the sea?’ asked Svenson.
    Chang shrugged. Miss Temple held up the lantern.
    ‘We forget
this
. Someone lit it. We must keep on and make her tell us everything.’
    A quarter-mile brought the tunnel’s end: a wooden door, and another red envelope left atop its polished handle. Chang tore it open, glanced at the paper and passed it to Svenson with a snort.
My Dear Doctor,
    As a man of evident Vitality you would have found this Lair in Time, but Time is no good Friend.
    The Task is beyond any single Agent.
    Do not let Love blind your Eyes. Ample Time remains to settle our Account.
    RLS
    Miss Temple raised her eyebrows impatiently and Svenson handed the paper to her.
    ‘Why should she mention “love”?’ asked Chang.
    ‘I expect she means Elöise,’ Svenson replied, wondering if it were true, wondering – despite his surety of the woman’s heartlessness – just how the Contessa viewed their encounter. And how did
he
view it? ‘She will say anything to mitigate her guilt if she requires our aid.’
    Miss Temple thrust the paper back. ‘I will not be a party to her bargains.’
    ‘If we find the Contessa,’ said Chang, ‘no matter where, she is to die.’
    Svenson nodded his agreement. It was not that he wanted to spare the Contessa – and he did not, truly – but he saw in his companions’ resolve a wilful denial of the fact that their struggle now stretched beyond the individuals who had wronged them. And if he did keep the woman alive to defeat the Comte, would Miss Temple and Chang come to hate him just as much, at the end?
    The