home in the alley. Of course, it wasn’t just an alley back then, when the book was written. It was called Streamside Path.’
Tate’s eyes flickered.
‘Page 201, if you’re interested.’ Bryant flicked through and allowed the book to fall open at the marked spot. He waited while Tate studied the picture.
‘I wonder how many other tunnels there are beneath the terraces around here,’ he mused. ‘Three or four, at least.’
‘Seven,’ murmured Tate without thinking. ‘All forgotten.’
‘Not by you. I presume their waters run into the Regent’s Canal.’
‘Some. Not all.’
‘Why not?’
No answer.
‘I just want to know what happened. I can see it’s painful to talk about these things. But there are other ways. Can’t you give me some guidance, put me on the right track? The river Fleet, I know it’s connected, but I don’t understand its significance.’
‘The river is where it all started. It has the power to change lives.’
‘You could show me.’
‘You’d tell.’
‘I couldn’t promise not to if I found evidence pertaining to the investigation,’ Bryant pointed out.
‘Then we won’t go.’
‘I can give you anonymity. No one will know it was you who took me. Your identity would remain a secret.’
Tate thought for a moment. ‘Can you get more books?’
‘Easily.’
‘Do you swear?’
‘On my honour as a gentleman.’
‘Haven’t heard anyone say that for a long time.’ Tate eased himself from the bed and pulled a hammer from underneath the mattress. ‘We’ll need this.’
‘I don’t understand.’
‘It was a long hot summer. No rain from June the sixth until three weeks ago. Dried out all the river beds.’
‘You mean they became passable? I thought the grilles stopped large objects, including people, from moving along the conduits.’
‘Most grilles are rusty. Some are gone. Some are locked.’ He pushed his hand into a syrup tin and pulled out a filthy set of long-stemmed keys.
‘You can move under the streets?’
‘I could. Now it’s raining again. The channels have filled back up, but there are still ways.’ He left the room with surprising speed, even though old injuries had twisted his body on damaged hinges. The pair of them headed out down the stairs and into the wet street like fugitives.
When they reached the wire fence of the alley at the end of Balaklava Street, Tate slipped through the gap and beckoned to Bryant. He stopped above the grating that Brewer Wilton had lowered himself into. ‘Give me a hand.’
Tate groped about in the bushes for his iron T-rod, and together they eased the steel lid off the drain. The water level had risen since Bryant had examined it, and a dull roar of water could be heard in the distance. ‘What’s that noise?’ he asked.
‘Gospel Oak sluice emptying into the Regent basin.’
‘But Gospel Oak is about half a mile away.’
‘Sound carries down there.’ Tate dropped to his knees in the mud and lowered the top half of his body into the hole. After a minute of searching, he emitted a grunt of satisfaction, withdrew the hammer and gave something in the hole a great whack. There followed a grinding metallic noise, and the rushing water seemed to ease off.
‘What have you done?’ asked Bryant.
‘Obvious. Can’t get down there if it’s full. I’m diverting the flow.’
‘You can do that?’
‘Smooth as a knife. Go down.’
Bryant looked dubiously into the shaft. The cement floor was visible a few inches beneath the water now, but the rungs to it looked slippery.
‘Want to show you something.’
‘I’m a bit dicey on my pins.’ Reluctantly, the elderly detective eased himself over the side of the drain, and began to climb down. They stood together on the draining concrete platform, heads ducked to avoid the low brick ceiling. The stench of rotting garbage and faeces settled into Bryant’s nostrils and clothes, but beneath it was another smell, something he had not expected: the damp bite of green Thames water. The temperature was lower than at ground level. His breath plumed before him as he clicked on May’s Valiant.
‘Look.’ Tate pointed through the olivine gloom at a pair of large oval holes on either side of the channel. The junction appeared deeper; water churned in a putrid eddy of cross-currents. ‘The Prince of Wales Causeway. Six gates to close off before you reach the basin. Can’t leave the gates shut more than a few minutes because of the pressure. Takes a logical mind to remember the sequence and survive.’
‘The Water Board must know how to do it.’
‘So do I.’
‘You want us to go down there?’
‘Not today, not with the forecast. Takes more than an hour,