DR BOUE' on the geognosy OF GERMANY, 105 
these coaly or arenaceous rocks are almost always indurated 
or altered in a thousand various ways ; but I shall discuss 
this subject at another time. 
In the period subsequent to the Old Red Sandstone, the 
Basalts have protruded from below, probably at various ir- 
regular periods, even before the formation of chalk ; for the 
cones, hills, and veins of basalts, so well known around the 
Meissner, Eisenach, the Rhonegebirge, and Gottingen, 
seem to indicate such an age. But this is a point that re- 
quires very minute investigation, 
Germany possesses a great variety of basaltic deposits, 
most of which are analogous to those of Ireland, and to 
the most of those in Scotland. I say most of those in Scot- 
land, because I am now inclined to classify the few hills 
around Edinburgh, Arthur's Seat, Salisbury-craigs, and 
such like deposits, with those of Eissenach. These are 
certainly in Germany the oldest, and they comprehend some 
conical hills and veins in different parts. 
The other basalts in Germany can be divided into those 
which have been formed under water, like the preceding, 
and those which have flown in the open air. The first, like 
the basalts in Ireland and Scotland, posterior to the chalk 
formation, form conical or massive hills, a kind of plat- 
forms, or high plains very little inclined, and veins or dikes. 
The cones or hills are principally formed of various por- 
phyritic clinkstones, which take, as in the Mittelgebirge 
and Rhongebirge, the place of the trachyte of other great 
deposits. The group of Mezen, in Auvergne, presents the 
same fact, although it was probably formed above the wa- 
ter. The plateaux, or nappes, present the same variety of 
basalt and tuffs as Ireland and Scotland, and some points 
in Auvergne, and also the same calcareous and zeolitic sub- 
stances. 
