‹‹‹ Vitr. 8.3.9 | Table of Contents | Vitr. 8.3.11 ›››
10In the same manner, at Hierapolis, in Phrygia, a large head of hot water boils up, and is conducted by ditches round the gardens and vineyards. At the end of a year the ditches become incrusted with stone; and hence, making yearly cuts to the right and left, they carry off the incrustations, and use them for building field walls. This circumstance, as it appears to me, would naturally happen, if, in these spots, and in the land about, there be a juice or moisture whose nature is similar to that of rennet. For then, when this coagulating power issues forth from the earth, through the springs, congelation takes place by the heat of the sun and air, as is seen in salt-pits.
10In the same way, at Hierapolis in Phrygia there is a multitude of boiling hot springs from which water is let into ditches surrounding gardens and vineyards, and this water becomes an incrustation of stone at the end of a year. Hence, every year they construct banks of earth to the right and left, let in the water, and thus out of these incrustations make walls for their fields. This seems due to natural causes, since there is a juice having a coagulating potency like rennet underground in those spots and in that country. When this potency appears above ground mingled with spring water, the mixture cannot but be hardened by the heat of the sun and air, as appears in salt pits.