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masses of basalt appear to me to have been local outbursts. A 
similar history belongs to the columnar basalts of Monistrol on 
the Allier south-west of Le Puy and Bains. They overlie old river 
beds of a former Allier, but are not excavated by the present 
river, for it now runs through the decomposing granite. 
A pleasant walk from Le Puy through Brives and over the 
bridge on the Loire conducts us to a tributary of the Loire, and 
on the right bank of this stream is the Roche Rouge. This is a 
basaltic dike traversing granite, and is remarkable as showing 
the wearing away of the granitic rock by atmospheric influences, 
since the infiltration of the dike into a fissure, and the resistance 
of the Roche Rouge to the eroding agents. It is a romantic 
spot, the stream of the Lagogne flowing in a narrow channel 
through granitic rocks, and forming deep pools in which we saw 
trout shooting in and out of hollows in the rocks. Wild pinks 
were growing all around, and the tall pyramid of the Roche 
Rouge rises 200 feet above the river. The roadside between 
the river and the base of the basaltic dike exhibits an old river 
bed, many feet above the present stream. We traced the dike 
upwards nearly to the summit of the hill, and found that the 
granite immediately in contact with the igneous rock had decom- 
posed much more than that at a distance from the point of con- 
tact. We observed also that, even on so isolated a spot, vegeta- 
tion was far more luxuriant on the lava than it was on the 
granite. Wild flowers blossomed everywhere on the Roche 
Rouge, accompanied by butterflies hovering around, while hardly 
a plant flourished on the arid unfertile granite. Another dike 
cuts through the freshwater beds at Brunelet on the road from 
Le Puy to Issingeaux. 
Standing on Mont d’Ours or any of the heights above Le Puy, 
and looking westwards, we see the granitic range of La Mar- 
geride rising between us and the old miocene volcano of the 
Cantal, while southwards are the heights of Mezen. Mont 
Mezen itself is nearly 600 feet above the sea ; but the old 
volcano was probably much higher, as it was erupted on a much 
more elevated basis of granitic rocks than either the Cantal or 
the Mont Dore. Opposite Mont Denise, on the other side of 
the Borne, the basaltic plateau shows trachytic lavas overlying 
basalt, as if produced by separate outbursts. The demarcation 
of the two lavas may be seen even across the valley from Denise. 
An expedition may be made from Le Puy to the ruined castle 
of Lardeyrolle, which lies on the left of the road to Issingeaux 
and Arnoray. Here, in the middle of the sixteenth century, 
lived the “ terrible Baron des Adrets,” who espoused the cause 
of the Huguenot king of Navarre, and who with one of his fol- 
lowers, Blacon, once a knight of Malta, and afterwards a free- 
booter, laid siege to Le Puy, and sacked the church of St. 
