468 
THE CARBONIFEROUS VOLCANOES 
BOOK VI 
JJuling the final period of eruption, the outpouring of lava and discharge of 
ashes, neither in united thickness nor in horizontal extent, equalled those 
which had preceded them. When the r'olcanoes ceased their activity, the area 
continued to sink, and over the submerged lavas marine organisms crowded 
the sea-floor, so as to build up the Calmy Limestone. After that time 
volcanic action seems to have become extinct in this region, for no trace of 
any intercalated lava or tuff has been detected either in the overlying 
Mdlstone Grit or in the Coal-measures. The total thickness of rock in the 
Linlithgowshire volcanic ridge is about 2200 feet. It will probably not be 
an exaggeration to place the proportion of lava and tuff in that depth of 
material at nearly 2000 feet. 
The northern or Fifeshire district over which lavas were abundantly 
erupted stretches along the coast from Aberdour to Kirkcaldy and inland to 
near Lochgelly, as well as seawards to Inchkeith. It may comprise an area 
of about dO square miles. In many respects this is the most important 
locality in Britain for the study of Carboniferous volcanic history. The sea 
ha,s cut an admirable coast-section in which the structures of the rocks are 
laid bare. The bottom and top of the whole vmlcanic series can be seen. 
The vents and their relation to the lavas and tuffs that were emitted from 
them may easily be made out ; while the interstratification of well-known 
seams of rock in the Scottish Carboniferous system permits the sequence 
and chronology of the whole volcanic series to be traced with great 
clearness. 
Most of these features have already been described in foregoing pages, 
for the district is a typical one for the study of Carboniferous volcanic 
phenomena. Thus the group of vents about Burntisland has been illustrated 
by the Binn of Burntisland rising among the bedded lavas and tuffs. The 
characters of the Carboniferous basalt-sheets have been enumerated, together 
with their intercalated layers of tuff and bole, and their fine partings of 
ashy material that was thrown out ov’er the lagoons during the intervals 
between two outbursts of lava. But it may be of service if I insert here 
a detailed section of the whole volcanic series as it is displayed along the 
coast-section between Burntisland and Ivinghorn. The lowest intercalated 
lavas of tliat section lie a little above the horizon of the Burdiehouse 
Limestone, and are thus probaldy rather earlier than those of Linlithgow- 
shire. The highest reach up to the base of the Hiuiet Limestone. ^The 
volcanic energy manifestly died out here long before it ceased on the south 
side of the Firth. Let so vigorous was its activity while it continued, 
that it piled up one of the thickest masses of volcanic material anywhere 
to be seen among the puy-eruptions of the British Isles. The following 
tabular statement of the alternations of material in this great mass in 
descending order, was drawn up by me on the ground many years ago, 
before the construction of fortifications and other changes partly concealed 
the rocks. 
