GEOLOGY. 343 



ioned by the hand of man, under such conditions as forced upon him the 

 conclusion that they must have been deposited in the spots where they were 

 found at the very period of the formation of the containing beds. M. de 

 Perthes announced his discoveries in a work entitled " Antiquites Celtiqucs et 

 Antediluviennes/' in two vols., the first published in 1849, and the second in 

 18-37; but, owing in some measure to the admixture of theory with the facts 

 therein stated, his work has not received the attention it deserves. The late 

 discovery in the Brixham Cave, in Devonshire, of flint weapons in con- 

 junction with the bones of the extinct mammals, had brought the question 

 of the coexistence of man with them again prominently forward among 

 geologists, and determined Mr. Prestwich, who has devoted much attention 

 to the later geological formations, to proceed to Abbeville, and investigate 

 upon the spot the discoveries of M, de Perthes. He had there been joined 

 by Mr. Evans, and they had together visited the pits where flint weapons 

 had been alleged to have been found, both in the neighborhood of Abbeville 

 and Amiens. The chalk hills near both these towns arc capped with drift, 

 which, apparently, is continued down into the valleys, where it assumes a 

 more arenaceous character, and in these beds of sand, as well as more rarely 

 in the more gravelly beds. -._^Tpon the hills, mammalian remains have been 

 found in large quantities. They include the extinct elephant, rhinoceros, 

 bear, hyaena, tiger, stag, ox, and horse in fact, most of the animals whose 

 bones are so commonly associated together in the drift and caverns of the 

 Posrpliocene period. On the hills near Abbeville, and at St. Acheul, near 

 Amiens, the drift varies in thickness from about ten to twenty feet, and con- 

 sists of beds of subangular gravel, with large flints, and above them sands 

 containing the fragile shells of fresh-water mollusca, and beds of brick- 

 earth. It is among the basement beds of gravel, at a slight distance above 

 the chalk, that the flint implements are usually found. They are of three 

 forms: 1. Flakes of flint, apparently intended for knives or arrow-heads. 

 2. Pointed implements, usually truncated at the base, and varying in length 

 from four to nine inches possibly used as spear or lance heads, which, in 

 shape, they resemble. 3. Oval or almond-shaped implements, from two to 

 nine inches in length, and with a cutting edge all round. They have gen- 

 erally one end more sharply curved than the other, and occasionally even 

 pointed, and were possibly used as sling-stones, or as axes, cutting at either 

 end, with a handle bound round the centre. The evidence derived from the 

 implements of the first form is not of much weight, on account of the ex- 

 treme simplicity of the implements, which at times renders it difficult to 

 determine whether they are produced by art or by natural causes. This 

 simplicity of form would also prevent the flint flakes made at the earliest 

 period from being distinguishable from those of a later date. The case is 

 different with the other two forms of implements, of which numerous speci- 

 mens were exhibited, all indisputably worked by the hand of man, and 

 not indebted for their shape to any natural configuration or peculiar fracture 

 of the flint. They present no analogy in form to the well-known imple- 

 ments of the so-called Celtic or stone period, which, moreover, have for the 

 most part some portion, if not the whole, of their surface ground or pol- 

 ished, and are frequently made from other stones than flint. Those from 

 the drift are, on the contrary, never ground, and are exclusively of flint. 

 They have, indeed, every appearance of having been fabricated by another 

 race of men, who, from the fact that the Celtic stone weapons have been, 

 found in the superficial soil above the drift containing these ruder weapons; 



