Lisa said that when she was choking, you stood by and did nothing.
The cause of this choking of the pores is precisely the same as that described below in the case of sand filters.
Of country (in the beginning very steep, and at intervals almost level), where certainly it would have been arrested and all accumulated in a mound; but it must have been borne along by a great quantity of water, the effects of which may be distinctly recognized, not only in the filling and choking up even of the most narrow, intricate and remote parts of the buildings, but also in the formation of the tufa, in which water has so great a share; for it cannot be supposed that enough of it has filtered through so great a depth of earth.
These interior landslips, besides choking the pipes and breaking the communication, often produce sinkings at the surface.
Though the Boeotian climate suffered from the exhalations of Copais, which produced a heavy atmosphere with foggy winters and sultry summers, its rich soil was suited alike for crops, plantations and pasture; the CopaIs plain, though able to turn into marsh when the choking of the katavothra caused the lake to encroach, being among the most fertile in Greece.