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POPULAR SCIENCE REVIEW. 
fallen where they lie. The transported blocks described by Dr. 
Hooker are stranded against a low sloping hill at the mouth of 
the gorge. This low hill consists, as shown by sections in the 
streamlets, of basalt and moraine matter. In the moraine 
matter, Dr. Hooker found scratched and polished stones. No 
one can examine the section below the waterfall of the Tran- 
teine stream without seeing that the great blocks are masses 
transported from the upper part of the gorge, resting in moraine 
matter, and on sheets of basalt. The larger masses consist of 
felstone porphyry from the Pic de Sancy, but there are others 
of trachyte and basaltic lava which show signs of great weather- 
ing. On the right and left of the transported rocks the hills 
are weathered and rounded, and have blocs perches resting on 
them. Here, as far as I read the history, rest the relics of the 
last of the glaciers among the valleys of Mont Dore, stranded 
against the low hill which a glacier of larger size once swept 
over and stretched far down the valley towards Latour and 
Picherande. But why should glacier relics be preserved so well 
in the Tranteine valley and obliterated in that of the Dor- 
dogne? It is accounted for, in my opinion, by the great 
difference in the watershed of streamlets and the freedom, com- 
paratively, from the constant wear and tear of tributary rills of 
water rushing through the glacier debris. The Tranteine stream 
does not shift its bed as does the Dordogne, and the moraine 
matter and transported rocks, resting on the hill in question, 
are comparatively free from the wear and tear of running 
waters. For some reason or other it was also evident from the 
backward vegetation that the Tranteine valley is colder than 
that of the Dordogne. Professor Lasaulx, of Breslau, in a paper 
written in the “ Ausland” of 1867, directs attention to glacial 
phenomena near the village of Latour, and I regret that I did 
not receive the “ Ausland ” until after our return from Auvergne, 
for we also went to the Tranteine valley by the long, round- 
about route through the village of Latour. On reaching the 
basaltic platform on the road to Latour, and before reaching 
the pine woods, I thought it was impossible to account for the 
presence of some transported masses of trachytic lava which 
rest on basalt without the aid of ice. We pass by the remark- 
able basaltic rock known as the Eocher de Vendeix, and come 
npon a granite district and its deceitful weathering. At Latour 
are vertical faces of columnar basalt, dykes of which burst 
through the granite and strew the slopes with their debris. 
Between Latour and Bousquet M. Lasaulx describes 66 basaltic 
prisms polished on the surface by glacial action ; ” and “ erratics 
resting on rounded and polished granite.” 
The high road from Latour to Besse crosses the Tranteine valley 
about 1 £ mile from the village of Picherande, and the distance 
