Natural Il/.stun/. ■ 353 



" Immediately beneath the Hgnite, a bank six feet in thickness 

 occurs, of the nature of chalk ; and in which the works have 

 ceased. In some places, as at the vineyards of Auteuil, the 

 chalk occurs immediately after the clay." 



The lignite is peculiarly situated ; all the trunks are in the 

 same direction, nearly perpendicular to the banks of the Seine, 

 and inclined to the horizon. This circumstance suggested the 

 idea that traces of it might be observed when the waters were 

 low, in the banks of the river ; and it appears that enormous 

 trunks of trees are actually found on the corresponding bank, 

 and in the bed of the river. They differ in their nature from the 

 lignite, but this is conjectured to be caused by the continual 

 action of the water. 



This fossil wood is first found opposite the road to Autueil, 

 where it joins the main road to Sevres, and from thence, in 

 descending the river about a quarter of a league ; but there is 

 no trace of it up the river. Nor is any fossil-wood found on the 

 right bank of the Seine, in a direction perpendicular to it, beyond 

 the limits assigned to the county where the lignite is founil. 



The bones of large animals are frequently found in the black 

 clay which precedes the lignite. In digging a well lately, at the 

 house of M. Fortin, the labourers endeavoured in vain to 

 remove a large skeleton, with which they came in contact, in 

 consequence of the extent it occupied. Fossil shells are also 

 abundant in the lignite. Hence, and from the position of the 

 trunks, M. Becquerel supposes it possible that a great irruption 

 from the south-west may have caused the overthrow of a forest 

 giving rise to the lignite ; and that the bones belonged to the 

 animals which inhabited it. The idea is supported by a quota- 

 tion from M. M. Cuvicr and Brogniart, in which they notice the 

 general marks of such an irruption. M. Becquerel also sup- 

 poses that the succinite may be tVie resin of those trees, and 

 thinks that its dissimilarity with the resins now known, does 

 not oppose the idea ; since, as there are many remains of extinct 

 kinds of animals, there may be the same also of resins. — Journal 

 dc Phya. 89, p. 237. 



