It was decided to build a coffer-dam around this place which appeared to be a concealed entrance to a tunnel connecting the cove with the Money Pit. In removing the rock, a series of well-constructed drains was found, extending from a common center, and fashioned of carefully laid stone. Before the coffer-dam was finished, it was overflowed by a very high tide and collapsed under pressure. The explorers did not rebuild it but set to work sinking a shaft which was intended to cut into this tunnel and dam the inlet from the cove. One failure, however, followed on the heels of another, and shaft after shaft was dug only to be caved in or filled by salt water. In one of these was found an oak plank, several pieces of timber bearing the marks of tools, and many hewn chips. A powerful pumping engine was installed, timber cribbing put into the bottom of the shafts, and a vast amount of clay dumped on the beach in an effort to block up the inlet of the sea-water tunnel. Baffled in spite of all this exertion, the treasure-seekers spent their money and had to quit empty-handed. Forty years passed, and the crumbling earth almost filled the numerous and costly excavations and the grass grew green under the sentinel oaks. Then, in 1896, the cove was once more astir with boats and the shore populous with toilers. The old records had been overhauled and their evidence was so alluring that fresh capital was subscribed and many shares eagerly snapped up in Truro, Halifax and elsewhere. The promoters became convinced that former attempts had failed because of crude appliances and insufficient engineering skill, and this time the treasure was sought in up-to-date fashion. Almost twenty deep shafts were dug, one after the other, in a ring about the Money Pit, and tunnels driven in a net-work. It was the purpose of the engineers to intercept the underground channel and also to drain the pirates' excavation. Hundreds of pounds of dynamite were used and thousands of feet of heavy timber. Further traces of the work of the ancient contrivers of this elaborate hiding-place were discovered, but the funds of the company were exhausted before the secret of the Money Pit could be revealed.