370 
TUK GEOLOGIST. 
GEOLOGICAL TOPICS. 
THE PIRST TRACES OF MAN ON THE EARTH. 
( Continuccl from vol. ii., page 482.^ 
The first person to verify tlic geoiogical age of the flint-implement strata of 
the valley of the Somme was Dr. Rigollet, who in 1851 published his " Memoire 
sur des Instruments en silex trouves a Sajpt Acheul pres Amiens, et considcres 
sous les rapports Gcologique et Archeologique," * illustrated by five sections 
of the beds by M. DutUleux, and with drawings of the worked flints. After 
stating that on many oceasious the bones and teeth of fossil elephants had 
been met with in the same beds, he adds — " My curiosity was strongly ex- 
cited in the month of August last (1854), when M. Dutilleux, Member of the 
Society of Antiquaries of Picardy, informed me that he had found there also 
axes or instruments of flint evidently worked by the liand of man. This fact, 
however astonishing, was the less so as M. Boucher de Perthes had announced 
the like discoveries at Mcncheeourt and at the mill at Quignon, near the gates 
of Abbeville. "t 
Peeling tlmt these discoveries supported the statements of M. de Perthes, 
Dr. Rigollet thought the geological question the most important, and the first 
to be investigated. 
Accompanied by M. Buteaux, member of the Geological Society of Prance, 
and author of an excellent memoir " On the Geology of the Department of the 
Somme," Dr. Rigollet inspected the beds themselves. He induced also M. E. 
Hebert, the professor of geology of the Ecole Normal Superieure of Paris, 
who for mauy years had spared no labour nor travel in the special study of the 
quarternary deposits, to visit the excavations at Saint Acheul and Saint Roch, 
and the deposits at Abbeville, and to inspect the rich and curious collection of 
axes and worked flints of M. Boucher de Perthes. 
"At Abbeville, as at Amiens," says Dr. Rigollet, "the worked flints are met 
with solely at the lower part of the diggings, in the midst of the sand and 
gravel. Some of those found at Saint Acheul .are still covered Mnth a 
calcareous coating that at certain j)laees envcloiies the boulders and gravel, and 
which atllierent ganguc is met witli oidy in this stratum, and is not seen in any 
of the overlying beds. At Saint-Aeheul, from the same place where these pro- 
duets of human industry are met with, M. Dutilleux obtained the tusk of an 
elephant, and bones and teeth of extinct species of horse, ox, and deer, the 
substance of which is dense, and heavy, as if impregnated with calcareous and 
perhaps siliceous matter, and totally unlike the bones of men, oxen, or horses 
found in superficial deposits, which are porous and liglit, even when they date 
back for fifteen or sixteen hundred years." 
" Thus it is well established," M. Rigollet adds, "that these flint objects are 
not found in tlie briek-earth which forms the ujipermost stratum, nor in the 
intermediate beds of clay, sand, and small pebbles, but are met with exclusively 
in the veritable diluvimu." M. Rigollet collected upwards of four liundi'cd of 
* Amiens, 1854, Duval et Herment. 
t Part of M. Boucher de Perthes book was translated and embodied in " The Stone Period," 
by Dr. A. Hume, of Livei-pool, in 1851. 
