Vane descended the steep interior flue that ran from the study wall down to the lower basement foundations.
The air grew progressively colder and damp as he approached the lower stone levels of the house.
He knew that the manual hand-brace would eventually bore through the safe lock mechanism upstairs.
Once the thieves retrieved the combination ledger, their next destination would be the lower vault passage.
Vane emerged near the heavy iron security gate that guarded the entrance to the vault corridor.
The iron gate was locked with a double-deadbolt, but a six-inch gap existed between the bottom iron bar and the granite floor.
Vane flattened his long, supple body and glided under the iron bar without touching the cold metal.
Inside the vault corridor, the stone walls were lined with vintage copper plumbing pipes.
These pipes carried fresh water under high head pressure from the hilltop reservoir down to the estate's upper bathrooms.
A primary shut-off valve sat on the main pipe three feet above the stone floor.
The valve featured a heavy cast-iron wheel painted in faded red enamel.
Vane climbed the rough mortar joints of the stone wall beside the pipe with steady paws.
He balanced on the iron valve housing and inspected the wheel spokes with sharp concentration.
If he turned the wheel counter-clockwise, the internal water pressure in the feeder pipe would spike dramatically against the lower coupling joint.
The lower coupling was an old fitting held together by a corroded brass collar.
Vane placed his front paws on the top rim of the red iron wheel.
He suspended his entire body weight from the rim, using gravity and muscle to force the wheel to turn.
The ancient valve stem creaked loudly as it rotated a quarter-inch against its packing nut.
Vane reset his grip on the upper spoke and pulled downward with all his force once more.
The valve stem yielded with a dull groan and spun open three complete revolutions.
High-pressure water began to hiss furiously inside the copper line, creating a rising acoustic hum.
Vane dropped down to inspect the brass coupling near the stone floor.
A fine mist of water was already spraying through a hair-line crack in the corroded fitting.
Satisfied with the rising hydraulic pressure, Vane turned his attention to the corridor floor.
He retrieved several heavy wooden chock blocks from an old wine crate sitting in the corner alcove.
He arranged the wooden blocks in a precise zigzag formation across the narrow stone walkway.
In the dim lantern light, the blocks created an irregular obstacle course that would force anyone walking down the hall to watch their feet.
Above, a loud metallic thud signaled that the study safe door had finally been forced open.
Vane heard the heavy boots of the thieves hurrying toward the basement stairs.
"We have the ledger!" the taller man's voice reverberated down the stone stairwell.
"Let's get the diamond and get out before the rain starts," the second man replied.
Vane retreated into a small stone drain alcove beside the vault entrance, pulling his tail tight against his body.
The bright beam of a halogen flashlight pierced the darkness of the cellar corridor.
The two men hurried past the iron security gate, their eyes fixed on the vault door ahead.
"Watch your step," the second man warned, pointing his light at the wooden blocks on the floor.
"Step over them and keep moving," the taller man ordered, raising his boot to clear the first block.
As his heavy boot came down on the wet stone flag, his body weight created a sharp vibration that transferred directly to the stone wall.
The sudden shockwave proved to be the final breaking point for the over-pressurized copper coupling directly above his head.
The corroded brass collar ruptured with a deafening bang.
A powerful stream of ice-cold reservoir water blasted out of the broken pipe at full pressure.
The jet of water struck the taller man squarely in the face, knocking him backward off his feet.
He crashed heavily into the second man, and both intruders tumbled into the rising pool of water on the floor.
The halogen flashlight flew from the second man's hand, hitting the stone wall and shattering its bulb into darkness.
The cellar corridor was instantly plunged into total pitch blackness, filled with the deafening roar of high-pressure water.
Vane observed the wet spectacle from his dry perch, confident that the lower passage was now thoroughly defended.
He let out a soft, satisfied click of his tongue, knowing that his water trap had succeeded completely in disorienting the two trespassers.