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lage, and these granitic rocks now separate the freshwater basin 
of Le Puy from that of Emblaves. The cone of volcanic 
scoriae and cinders known as Mont Serre has been erupted on 
the edge of the granite escarpment ; and the basaltic plateau, the 
Chauds de Fay, rests upon the freshwater beds. Here, too, are 
the Rochers de Peylencs, famous for their great blocks of olivine, 
specimens of which may be seen in the museum. This brecciated 
mass is very peculiar ; surely the outburst must be local, and 
the blocks of olivine must have crystallized below the spot where 
they are now excavated. A great landslip has occurred, and 
let down masses of basalt, while the river Sumene rolls among a 
hurly-burly of debris and columnar ranges of basalt through a 
splendid gorge of rock and rushing waters. 
The town of Le Puy is situated nearly in the centre of an area 
which was a large freshwater lake during portions of the Eocene 
and Miocene epochs. This ancient lake must have been at least 
twenty miles in length, by ten or twelve in breadth, and occupied 
a depression between hills of granitic gneiss ; and probably the 
depression was caused by the subterranean movements preced- 
ing the great development of volcanic activity, which covered 
up the area occupied by the lake with lavas, breccias, and scoriae. 
High granite hills must have risen all around ; and there is 
little doubt that the granite peninsula of Chaspinhac which now 
divides the freshwater basins of Emblaves and Le Puy was a 
spur of high land jutting into what was in olden times a single 
lake. You might have sailed on its waters round by St. Paulien 
to Vaurey. It is probable that streams running from the same 
source as the present Loire and Allier flowed into the ancient 
lake ; for it is evident, from old river drifts now elevated high 
upon hills where now no waters flow, that former rivers were 
compelled by land movements and volcanic eruptions to shift 
their courses over and over again. Our time was far too limited ; 
and we only saw enough of Le Puy en Velay and its fossil re- 
mains to convince us that a series of events have occurred of 
magnitude and wonder, that are only yet foreshadowed to the 
geologist who searches for its past history, among silted-up lakes, 
ancient river beds, old granite hills, miles of lava torrents, and 
mountains of volcanic cinders and scorise. 
From Le Puy to Vais . — There is a diligence from Le Puy 
through Pradelles to Langogne, a station on the Issoire 
Railway ; but we strongly advise the geologist to make postal 
or other equine arrangements with our host at the Hotel des 
Ambassadeurs at Le Puy, and avoid the diligence. Arrange- 
ments should be made also for horses to be sent on ; for my 
companions, on a previous excursion a few months before, 
found that the best vehicle at Pradelles was a wretched “ shan- 
deradan,” “ and were dreadfully jolted over bonesetting roads.” 
