532 



IMBEDDING OF OEGANIC EEMAINS 



[Ch. XLVI. 



S 



Submerged forest in Bay of Fundy. —One of the best au- 

 thenticated examples of an old upland soil with trees, now 

 covered hy about thirty feet of water at high tide, occurs 

 at Eort Lawrence in the Bay of Fundy, near the boundary 

 between Nova Scotia and New Brunswick, Dr. Dawson, an ex- 

 perienced geologist and most careful observer, has shown that 

 below layers of marine marsh-alluvium containing shells of 

 Sanguinolaria fusca, (a bivalve shell probably identical with 

 Tellina Baltica, Linn.,) there is a bed of tough blue clay, 

 and beneath it an old peaty soil with erect trunks of tree 

 and roots. All the stumps observed were those of pine and 

 beech {Pinus strohus and Fagus ferruginea) , trees indicative 

 rather of dry upland than of swampy ground. The largest 

 stump of a pine measured two and a half feet in diameter 

 and exhibited about 200 rings of annual growth. Dr. Dawson 

 counted thirty stumps in a limited area, and the same forma- 

 tion occurs at so many points as to lead him to infer that there 

 has been a very general sinking down of the land in the 

 same district. The powerful tides of the Bay of Fundy, rising 

 and falling 40 feet, cause this formation to be peculiarly well 

 exposed to view at many points, the deposit being laid bare 

 by the continual encroachments of the sea."^ 



—Although the botanist and chemist 



Mineralisation of plants.— 

 have as yet been unable to explain fully the manner in which 

 wood becomes petrified^ it is nevertheless ascertained that, 

 under favourable circumstances, the lapidifying process is 

 now continually going on. A piece of wood was procured by 

 Mr. Stokes, from an ancient Roman aqueduct in Westphalia, 

 in which some portions were converted into spindle-shaped 

 bodies, consisting of carbonate of lime, while the rest of the 

 wood remained in a comparatively unchanged state. f It 

 appears that in some cases the most perishable, in others the 

 most durable, portions of plants are preserved, variations 

 which doubtless depend on the time when the mineral matter 

 was supplied. If introduced immediately, on the first com- 

 mencement of decomposition, then the most destructible 



* Dawson, Submerged Forest at Fort 

 Lawrence, Quart. Geol. Joitrn., vol. xi. 

 p. 119. 1854:. 



t Geol. Trans., second series, vol. v. 



p. 212. 



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