agglomerated above, under and close to each other, and here and there thoroughly mingled together. This granite rock is pierced in different places by lines of hornstone (chert), the mightiest of which can be traced nearly to the whole so-called Hoff’s line (vide map), at which point the mineral springs appear, and are for this very same reason perhaps genetically connected with them. The granite cleft, giving rise to the springs, was probably closed in previous times, so as to allow the mineral water to accumulate as in a pond; this would account for the formation of the Sprudel shell, which was deposited therein in the course of time and still can be found in perfect layers, to the height of from 20 to 50 feet above the level of the Sprudel. This pond was afterwards broken into, in consequence of the formation of the vale, and in course of time was split into what is now called the valley of the Tepl. As soon as the waters of the Sprudel could flow into the river, there was of course no possibility of any more external formation of Sprudel shell. On this Sprudel shell is built the principal part of the houses of the Marktplatz, the Mühlbrunn Sprudel and Kreuzgasse. The fragments of this shell fornt the Sprudel stones, which are mostly so hard as to allow of polishing, and are consequently turned into ornamental articles.
