"Ten miles!" echoed the other. "Well, if Fenton knows anything about driving it's going to be a pretty close business."
Breaking into a run, they hurried along the road to where they had left the car, and with a sharp jerk of the handle Colin set the engine in motion. Followed by the Inspector, he scrambled into his seat, and a few seconds later he had backed hastily along the oak paling, and swung round into the side turning which ran southward across the marshes.
It was not a route that any one who was fond of his life would have selected deliberately for the purposes of fast driving. Narrow and winding, with a thick coating of mud plastered over its surface, it presented such obvious dangers that even the most foolhardy of motorists would have been forced to recognize the advisability of caution.
Caution, however, was the particular virtue which Colin felt least able to afford. Unless he could make up his lost ground on the more difficult stages of the journey he could certainly abandon all hope of success, for on an open and moonlit road Fenton's progress would probably be as fast as his own.
With a full appreciation of the chances that he was taking he therefore let out the car to a pace which in any other circumstances he would never have attempted. Bumping over patches of loose stone, and splashing through pools of water, he held resolutely on, regardless of risk, while all the time immediately ahead of him two broad and recently imprinted tire marks stretched away encouragingly through the mud.
Whatever the Inspector's private emotions may have been, it must be admitted that he faced the ordeal with masterly restraint. Once or twice, as they skidded violently round a blind corner, he caught hold of the side door with a spasmodic grip, but except for this instinctive movement he maintained an expressionless calm which certainly did credit to the self-discipline of the Yard.
For the first three miles Colin needed all his skill and luck to avoid disaster; then, as they drew farther out into the lonely marshland which borders the north bank of the Thames, the conditions gradually improved. The east wind, which blows perpetually over that desolate region, had already begun to dry up the surface of the road, while with nothing but an occasional cowshed or a few leafless trees to obstruct the view, the chances of running headlong into some unforeseen death trap were reduced to much more comforting proportions.
Suddenly, with an abrupt movement, the Inspector pointed ahead, to where a broad shaft of yellow light streamed out against the sky.
"What's that?" he demanded, putting his lips close to Colin's ear.
"Mucking Lighthouse," was the answer. "There are some powder works away to the right, and the creek they're making for is just between the two."