22 2 THE POPULAR SCIENCE MONTHLY. 



out an outlet, where sanidin bombs may reward the seeker, and 

 bits of underlying Devonian slate are strewn through the strata 

 of volcanic ash. Returning to Gillenfeld, we had a little some- 

 thing to eat and drink — the Germans never neglect the inner 

 man — and went on past its crater-lakes to Daur, where we dined 

 at Hotel Hommes. On the card of this inn is a sketch-map of 

 the Eif el, and a geological map and minerals are about the house. 

 While waiting for dinner we picked up a lot of augite crystals 

 from the locality near by. After dinner we hired a dray-cart 

 and pushed on to Dreis, arriving there late, to spend the third 

 night. The next morning, after collecting basaltic hornblende 

 east of the town, in crystals up to the size of an egg, mostly 

 rounded a little by fusion, and taking also some of the olivine 

 bombs, of which so many are scattered through the museums, 

 we went rather across country to Gerolstein. There is much of 

 interest on the way, first petrographic, afterward more paleon- 

 tologic. 



From Gerolstein various further excursions can be made. A 

 visit to the ice-cave of Roth is refreshing in the heat of summer. 

 But the summer tourist must not tarry. So on to Treves, and 

 down the Moselle and up the Rhine, till passing through the 

 ridge of Taunus we emerge into the upper plain of the Rhine at 

 Bingen. From Bingen a side excursion to Miinster-am-Stein, if 

 no farther, is of great interest and beauty (17), and those who 

 are attracted by the silver sheen of tiger-eye, the peacock hues of 

 labradorite, or the delicate tracery of moss-agate, should not give 

 Oberstein the go-by. Here, and near by, the semi-precious stones 

 are polished for all Europe, and from Heinrich J. Steffen can be 

 obtained specimens of the melaphyres in whose cavities agates 

 are wont to come, and of the fossils of the region — trilobites and 

 ophiuroids. The view from the station of town and river, and 

 above two castles and a church curiously let into the rock, is said 

 to be one of the three finest on the Rhenish railways. 



Near Kreuznach I may mention Hackenheim churchyard 

 and a little southeast as a place where fossils of the Mayence 

 basin abound, and the valley from Kreuznach to Winterburg 

 and back over the Welschberg, with its patch of Tertiary to 

 Bockelheim, as giving a good section of the country. If you 

 want to see more of the Mayence basin, a good way will be to 

 seek the tall chimneys of the cement-factories and the neighbor- 

 ing limestone and clay-pits — e. g., those of Wiesenau. From this 

 region immense quantities of cement are exported to America. 

 The two sides of the great Rhine Valley, which has till recently 

 been considered a typical case of dropping in, are not unlike. 

 Most people go down the east side, and we will follow them. 

 The Taunus region has some interesting porphyroids and sericite 



