324 
important places. Accepting sucli things as human work, 
I will just enumerate a few of the many districts where they 
are found, to show that it is not an exceptional case to be 
explained by some local cataclysm caused by the sudden up- 
heaving of the land, perhaps with earthquake shocks, or to the 
bursting of a barrier where the waters long pent up rushed 
down and filled the valley. We have to deal with facts so 
clear, so numerous, so widespread, and so similar everywhere, 
that we see we must at once refer them to the common ways 
of river denudation. 
Along the Somme, loam, sand, and gravel, nearly a hundred 
feet above the river level of to-day, have yielded these works 
of man. We know that they are river gravels, from the shells 
that they contain. Similar implements are found along the 
Garonne, and in the basin of the Loire. They are brought 
from Africa and from India. In our own country, in the 
valleys of the Thames, the Ouse, the Medway, and the Avon, 
at 40, 50, 60, 80 feet above the river level ; along the Solent and 
the coast near Barton, and near Bournemouth, and in the Isle 
of Wight, in terraces of ancient rivers, 100 to 150 ft. above the 
sea, they have been found. Everywhere in these older beds, 
with nearly the same groups of animals, the same types of instru- 
ments are found, distinct from later forms, quite recognisable. 
And in caves we find traces of man with the extinct and 
migrated mammalia. In the Dordogne they have been classi- 
fied by date, La Madelaine, the two Laugeries, and Le Moustier, 
the oldest being Le Moustier. In our own country, on the 
coast of Devon, in the cliffs of Yorkshire, Derbyshire, in 
Wales both North and South, along the Wye, and almost 
wherever limestone crags are found, these caves have fur- 
nished shelter to an early race of man. I do not know that 
as yet any exact relation has been established between a 
cave with works of man and any terrace with the same. A 
diagram on the screen shows the position of one of the cele- 
brated Pyrenean caves (Gourdan)* with reference to the higher 
terraces of river gravel opposite to it. They stand at the same 
height above the river. This cave contains the usual group of 
extinct and migrated mammalia, and of man abundant evi- 
dence in bone and stone, of which examples lie upon the table. 
The terraces immediately opposite have not, so far as I am 
aware, yielded remains of man, but lower down the river 
instruments of palaeolithic typo have been procured by 
M. Noulet, and may be seen in the Museum at Toulouse. 
* Piette, Acad, den Sci. 31 Juil., 1871 ; Matiriaux pour VHiet. dc 
I’Hovime, 1871, p. 494. 
