412 
THE CARBONIFEROUS VOLCANOES 
BOOK V] 
But perhaps the most striking contrast between adjacent localities in 
regard to the distance between the limestone and the top of the volcanic 
series is to be observed along the southern front of the Campsie Fells. In 
spite of the abundant faults wdiich have there so broken up the regular 
sequence of the rocks, we can see that at Banton and Burnhead the lime- 
Fio. 139.— Section across tlie upper surface of tlie Clyile volcanic plateau, Burnlieail, north-west of 
Kilsyth. 
Lavas of the plateau ; 2. Tuffs; 3. Hiirlet Limestone ; 4. TTosie’s Limestone. /, Fault. 
stone lies almost immediately on the volcanic series (Fig. 139). But a 
little to the westward, sandstones, conglomerates, shales and thin limestones 
begin to intervene between tlie volcanic series and the Hurlet Limestone 
and swell out so rapidly that on Craigmaddie Muir and South Hill of 
Campsie, only some five miles off, tliey must form a total thickness of not 
Kio. 140.— Section iwross the tipper surface of tlie Clyde volcanic plateau at Campsie. 
1 . 
Shales, saiulstoucs, cement-stones, etc. (“Ballasan Beils ”) 
saiulstone and consloineratc ; 4. Hurlet Limestone ; 
; 2. Lavas of the plateau ; 3. Thick white 
5. Hosie’s Limestone ; /. Fault. 
less than from 600 to 800 feet of ordinary non-volcanic deposits, chiefly 
thick pebbly sandstones (Fig. 140). Sucli local variations not improbably 
serve to indicate hollows on the flanks of the plateaux that were filled up 
with detritus before the depression and clearing of the wvater tliat led to the 
deposition of the Hurlet Limestone. 
1 have already remarked that the eruptions of the plateau period lasted 
Fig. 141. — Section across western edge of the Garleton plateau. 
1. I rachj^rte lavas of tlin plateau ; 2. Calciferoiis yandstnnR.s ; 3. Hurlet Limestone. 
longei' in the western than in the eastern parts of the region. In the 
Garleton district, where the peculiar viscous trachytic lavas probably gave 
rise to a more uneven surface or more prominent cones than was iisual 
among the andesitic plateaux, the eruptions ceased some time before the 
