THE GEOLOGY OF THE FAROE ISLANDS. 267 
Ix. EXPLANATION OF PLATES. 
PLATE XIII. 
Fig. 1. Represents a horizontal section, drawn along the line A.B., upon the map, across the 
Island of Suderée. The horizontal and vertical scales are the same. The horizon of 
the thin coal got at Dalbofos is shown by a thick line; but it must be understood 
that the coal itself has been found only at one place. The beautiful columnar basalt 
of Frodboe is shown at 0. 
Fig. 2. This is a diagrammatic representation of the form of the ground between Saxen and 
Tidrnevig in Stromoe. 
Fig. 3. Is a similar diagrammatic section across Osterée, between the sea at Eide and the head 
of Fundingsfiord. These sections illustrate a very common feature in the valleys of 
the Feerée Islands, many of which descend in successive platforms. 
Fig. 4. Is a horizontal section, drawn to same scale as fig. 1, across the north end of Suderde 
along the line C.D, 
ig. 5, Sketch-section of an exposure of strata at the coal-workings of the Prestefield (Suderée), 
at a height of 147 métres above the sea, The coal occurs in two layers, and is sepa- 
rated by 4 to 6 inches of shaly clay.. The shales overlying the coals are interlaminated 
with lines and thin seams of glance coal, which are sometimes as much as 3 or 4 
inches thick. There is a good deal of iron pyrites in the shales and coal-lines above 
the coal. The reference letters are as follows :— 
d. Tumbled blocks and superficial débris. 
t. Till or boulder-clay. 
2. Nodules of coarse grey arenaceous clay-ironstone ; 1 to 3 inches in diameter. 
s. Dark shales and clays with lines and layers of glance coal and common coal ; 
about 8 feet thick. 
cl. Glance coal; 8 inches, 
d. Dark shaly clay or clunch; 2 to 8 inches. 
e?. Coal; 2 feet. 
g. Space covered with grass and débris ; tufaceous shales. 
a. Dark anamesite. 
The dip is north-east at 5°. 
Fig. 6. Sketch-section of strata at Preestefield (Suderoe), near the place shown in fig. 5. The 
spot is 161 métres above sea-level; the dip of the strata is towards north-east at 3°. 
The reference letters are as follows :— 
t. Till or boulder-clay. 
s. Shales and clays, about 12 feet thick, with layers and seams of coal, as in 
section fig. 5. The coal-lines are lenticular, and are most abundant in the 
shales immediately overlying the thick coals ; towards the top of the section 
they are less plentiful. 
z. Ironstone nodules in shales. 
cl. Coal; 8 inches. 
d. Shale or clay ; 4 inches. 
c?, Coal; 1 foot 2 inches. 
Ea 
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