We must not omit to state, before leaving the subject, that it is now ascertained, by a series of accurate observations, that the Crust of the Earth in this interesting locality is once again slowly and gradually subsiding. At the beginning of the century the platform of the temple stood at about the level of the sea; it is now more than a foot below it. Nay, this second subsidence appears to have begun even before the present century. “In the year 1813,” writes a modern traveller, “I resided for four months in the Capuchin convent of Pozzuoli, which is situated between the road from Naples and the sea, at the entrance of the town of Pozzuoli. In the Capuchin convents the oldest friar is called ‘il molto reverende,’ and the one who then enjoyed the title in this convent was ninety-three years old. He informed me that, when he was a young man, the road from Naples passed on the _seaward side_ of the convent; but that, from the gradual sinking of the soil, the road was obliged to be altered to its present course. While I was staying at the convent, the refectory as well as the entrance gate, were from six inches to a foot under water whenever strong westerly winds prevailed, so as to cause the waters of the Mediterranean to rise. Thirty years previously, my old informant stated, such an occurrence never took place. In fact, it is not probable that the builder of the convent would have placed the ground-floor so low as to expose to inundation as it now is.”[102]
On the shores of the Baltic Sea we find another illustration of our theory upon a more extended scale. About a century and a half ago the Swedish naturalist, Celsius, expressed a belief that a remarkable change of level was taking place along the eastern coast of Scandinavia; and he ascribed the change to a subsidence of the waters of the Baltic Sea. This opinion was received at first with no small amount of incredulity; but the arguments of Celsius were plausible and attractive enough to excite a controversy, and the controversy once aroused was not easily set at rest. Accordingly, since his time the facts upon which he relied have been more strictly examined, difficulties have been started and investigated, many new facts, at first unknown or unnoticed, have been brought to light, and the whole question has been rigorously discussed by scientific men. It would be tedious to go through the history of the discussion, or to develop at any length the arguments which in the end have proved successful, involving as they do a multitude of minute observations and nice measurements, made at a great variety of different places with hard-sounding names. But the general result may be readily stated and as readily understood.