Gaston Leroux: The Phantom of the Opera

Chapter 20. In the Cellars of the Opera (continued)

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[6] All the water had to be exhausted, in the building of the Opera. To give an idea of the amount of water that was pumped up, I can tell the reader that it represented the area of the courtyard of the Louvre and a height half as deep again as the towers of Notre Dame. And nevertheless the engineers had to leave a lake.

The Persian touched a partition-wall and said:

"If I am not mistaken, this is a wall that might easily belong to the house on the lake."

He was striking a partition-wall of the "tub," and perhaps it would be as well for the reader to know how the bottom and the partition-walls of the tub were built. In order to prevent the water surrounding the building-operations from remaining in immediate contact with the walls supporting the whole of the theatrical machinery, the architect was obliged to build a double case in every direction. The work of constructing this double case took a whole year. It was the wall of the first inner case that the Persian struck when speaking to Raoul of the house on the lake. To any one understanding the architecture of the edifice, the Persian's action would seem to indicate that Erik's mysterious house had been built in the double case, formed of a thick wall constructed as an embankment or dam, then of a brick wall, a tremendous layer of cement and another wall several yards in thickness.

At the Persian's words, Raoul flung himself against the wall and listened eagerly. But he heard nothing...nothing ... except distant steps sounding on the floor of the upper portions of the theater.

The Persian darkened his lantern again.

"Look out!" he said. "Keep your hand up! And silence! For we shall try another way of getting in."

And he led him to the little staircase by which they had come down lately.