156 Mr Poulett Scrope's observations on the Volcanic 



duced much lava. Eastward of Waldsdorf lies the Drieser 

 Maar, a wide crater, which has been artificially drained. 

 Masses of olivin, often of three or four pounds weight, and as 

 large as a man's head, are found in the fragmentary strata 

 which form the sides of this basin. Part of this encircling 

 ridge rises into a high cone on the south-west, and this is again 

 connected with a third hill above Dockweiler, which exhibits 

 a well-characterized crater at its summit, and has sent forth 

 powerful streams of basaltic lava. The road from hence to 

 Daun, leaves on the right three or four considerable cones 

 near Nerod and Steinborn. They consist in a great part of 

 lava which has burst from their summits or flanks, and flood- 

 ed the lowest levels of the surrounding plain. 



On the east of Daun, a massive and elevated bed of basalt, 

 bordered by abrupt cliff-sections, in which a rudely columnar 

 configuration is visible, descends towards the town from a 

 higher eminence at its eastern extremity, which is composed of 

 scoriae, and exhibits vestiges of a crater. This bears the ap- 

 pearance of being the least recent of all the volcanic forma- 

 tions of the neighbourhood. 



South of Daun rises a group of hills which appear, as they 

 are mounted, to be solely composed of greywacke slate, and 

 in which, consequently, no volcanic appearance could be anti- 

 cipated, when, on reaching the summit, the traveller sudden- 

 ly finds himself on the edge of a deep circular lake-basin, evi- 

 dently drilled through the greywacke by repeated and power- 

 ful discharges of subterranean vapour. There are three of 

 these maar strung together on a line, in a N. S. direction, 

 and in immediate contact, the same ridge forming the barrier 

 of two neighbouring craters. The fragments of which the sur- 

 rounding slopes are formed, consist chiefly of slate partially 

 calcined, the remainder of augitic scoriae. A large rock of grey- 

 wacke slate, evidently in situ, projects from the bottom of one 

 of these basins. The water in the three lakes appears to stand 

 at the same level, and they probably communicate by means 

 of some fissures in the intervening rocks. One only, the 

 Schalkenonchrener maar, has any visible outlet, and there are 

 traces of trass-streams in that direction. 



A few miles farther to the south, the Polvermaar of Gil- 

 lenfeld, is met with ; a magnificent oval basin, presenting ex- 



