192 PROF. BONNEY ON THE RELATION OF BRECCIAS [May 1902, 
apparently become a little larger towards the summit. They 
consist of vein-quartz (abundant), fine-grained grey granite and 
gneiss, a micaceous schist, felstone, and slaty rock or grits. At 
Ruhla, in the bed of a well-marked valley which opens out some 
4 miles east of Hise- 
Fig. 1.—Section near the railway-bridge, nach, a lead-coloured 
Georgenthal, Eisenach. micaceous schist is 
exposed, and about 
lS half a league farther 
eee up, a porphyritic gra- 
nite; and more than 
one variety of felstone 
is passed on walking 
over the _ elevated 
upland to the Hohe 
Sonne, south of 
Hisenach. At Fried- 
richsroda, about 12 
miles east by south 
of Ruhla, Permian 
‘porphyries’ abound ; 
but some bedded 
Rothliegende is seen, 
in which is an occa- 
sional seam of small 
0 = Breccia: about breccia. According 
10 feet: visible. to the geological 
1 = Banded marly map, the breccia in 
sandstone. 93 feet. the Eisenach district. 
a ert About occupies an area mea- 
eee About SUring at first nearly 
: 3 feet. 4 miles from west to. 
0 f.>0. wha? 4 = Breccia. About east, but narrowing 
9) 2 ima sandstone towards ches jegualy 
. with marly parting. and about 9 miles ae 
a ge Atoutisiesr a transverse direction. 
ae 6 = Breccia. About The mica-schist, such 
a 18 feet. as we see at Ruhla, 
7 Peaaedaantehe. extends about 5 miles 
in places. along a line from a 
little east of north to 
west of south, and half that distance in a direction at right angles. 
to this. Then comes the granite, which at first is a mere strip, but 
broadens out southward until it nearly replaces the other rock. 
East of these crystalline rocks Permian deposits set in again. Thus 
the area of more ancient rocks, which can have been exposed in 
Rothlegende times, does not exceed 3 miles in breadth, and so cannot 
then have been surmounted by an important mountain-range.! 
1 If the average slope were 1 in 10, the height of the part removed would. 
be about 800 feet. 
