58

WILDBAD.

CHAFT. IV.

district. To thcse very likcly belongs llic gianl-stone near Wildbad, mentioncd in a preceding cbapter. The varic- gated sandstone of tbe Black Forest contains no traces of calcareous matter, but a high proportion of silicia entcrs into its composition, as well as some oxide of iron, which gives to it tbe red, porphyrc-like appearance. Owing to this cause it is excellcntly well adapted for building pur- 4 poses, it heilig not decomposed by contact witli tbe outer air. Its extreme durability is proved by tbe Strassburg ca­thedra!, which is entirely built of variegated sandstone, and whose aspect is still tbe same it was, wlicn left by tlie stone-mason. The bath-lmildings of Wildbad, and all tbe Principal edifiees of the town, are also eonstructed of this sandstone.

The granite rock, as already stated, is but rarely met with in the northern parts of the Black Forest. It only appears in the valley of the Murg, near Reichenbach and Schwarzenberg; from Enzklüsteile to Wildbad, in the valley of the Enz; and near Herrenalb, where it forms an aggre- gate of high peaks, resembling towcrs eonstructed by the band of man, which are ealled the Falkensleine or hawk’s stones.

At Liebenzell also a granite-gang may be pcrceived, wedged ip between the variegated sandstonc, in an eleva- tion of 995 Par. F. above the sea-level. Considering thcse instances of the appearance of granite rocks linder a balneo- graphical point of view, we at once perceivc, that it gives origin to all the warm springs of the district, and this fact becomes the more remarkable, if we know that in the Gais- thal near Herrenalb, in a spot almost touching a line drawn from Wildbad to Baden-Baden, a thermal spring has been discovercd some ycars ago. These observations will Iead ns to iqfer, that there exists probably a subterraneous con-