While the work was in progress,
the excavation was kept free from water by means of eight pumps,
worked by steam power, and in operation, without interruption,
day and night, from March second to October thirteenth. The floor
of the cellar was covered with a layer of concrete, then with two
coats of cement, another layer of concrete and a coat of bitumen.
The wall includes an outer wall built as a coffer-dam, a brick wall,
a coat of cement, and a wall proper, a little over a yard thick.
After all this was done the whole was filled with water, in order
that the fluid, by penetrating into the most minute interstices,
might deposit a sediment which would close them more surely and
perfectly than it would be possible to do by hand. Twelve years
elapsed before the completion of the building, and during that time
it was demonstrated that the precautions taken secured absolute
impermeability and solidity.
"The events of 1870 interrupted work just as it was about to be
prosecuted most vigorously, and the new Opera House was put
to new and unexpected uses. During the siege, it was converted
into a vast military storehouse and filled with a heterogeneous
mass of goods.
Pages:
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400