He had by this time reached the ground, and he stood flashing his torch about on his surroundings. He was in a cellar, so low in the roof that except immediately beneath the stairs he could not stand upright. It was square, some twelve feet either way, and from it issued two passages, one apparently running down under the wharf, the other at right angles and some two feet lower in level, leading as if towards the distillery. Down the center of this latter ran a tiny tramway of about a foot gauge, on which stood three kegs on four-wheeled frames. In the upper side of each keg was fixed a tun-dish, to the under side a stop-cock. Two insulated wires came down through the ceiling below the cupboard in which the telephone was installed, and ran down the tunnel towards the distillery.

The walls and ceiling of both cellar and passages were supported by pit-props, discolored by the damp and marked by stains of earthy water which had oozed from the spaces between. They glistened with moisture, but the air, though cold and damp, was fresh. That and the noise of the waves which reverberated along the passage under the wharf seemed to show that there was an open connection to the river.

The cellar was empty except for a large wooden tun or cask which reached almost to the ceiling, and a gunmetal hand pump. Pipes led from the latter, one to the tun, the other along the passage under the wharf. On the side of the tun and connected to it at top and bottom was a vertical glass tube protected by a wooden casing, evidently a gauge, as beside it was a scale headed “gallons,” and reading from 0 at the bottom to 2,000 at the top. A dark-colored liquid filled the tube up to the figure 1,250. There was a wooden spigot tap in the side of the tun at floor level, and the tramline ran beneath this so that the wheeled kegs could be pushed below it and filled.

The inspector gazed with an expression of almost awe on his face.

“Lord!” he muttered. “Is it brandy after all?”

He stooped and smelled the wooden tap, and the last doubt was removed from his mind.

He gave vent to a comprehensive oath. Right enough it was hard luck! Here he had been hoping to bring off a forged note coup which would have made his name, and the affair was a job for the Customs Department after all! Of course a pretty substantial reward would be due to him for his discovery, and there was his murder case all quite satisfactory, but forged notes were more in his line, and he felt cheated out of his due.

But now that he was so far he might as well learn all he could. The more complete the case he gave in, the larger the reward. Moreover, his own curiosity was keenly aroused.

The cellar being empty save for the tun, the pump, and the small tramway and trucks, he turned, and flashing his light before him, walked slowly along the passage down which ran the pipe. He was, he felt sure, passing under the wharf and heading towards the river.

Some sixty feet past the pump the floor of the passage came to an abrupt end, falling vertically as by an enormous step to churning waters of the river some six feet below. At first in the semi-darkness Willis thought he had reached the front of the wharf, but he soon saw he was still in the cellar. The roof ran on at the same level for some twenty feet farther, and the side walls, here about five feet apart, went straight down from it into the water. Across the end was a wall, sloping outwards at the bottom and made of horizontal pit-props separated by spaces of two or three inches. Willis immediately realized that these props must be those placed behind the inner or raking row of piles which supported the front of the wharf.