Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.2): between the years 1826 and 1836 : describing their examination of the southern shores of South America, and the Beagles's circumnavigation of the globe

ON THE DELUGE. ()77 the waters, other substances, such as earth, mud, bones, animal and human remains, &:c., may have been held at various depths until decomposed by water ; or combined and consoli- dated by volcanic gases, or electric currents. In this manner the preservation of delicate corallines, shells, skeletons of animals, &c., may be accounted for. Suspended in water, surrounded by earth in a dissolved state, combined by che- mical agency, deposited on land, and consolidated by pressure, by volcanic or by latent heat, they may have become fossils. "J'hick skinned animals may have floated longest, because their hides would have buoyed them up for a greater length of time,* hence their remains should be found near, or upon the surface of the ground, in some cases water- worn, in others uninjured, according as they had been strewed among shingle, or deposited in a yielding mass. That bones were not roUed about much among the stones in which they are found,-|- is evident from the fact that bones, if so rolled among them, would soon be ground to powder. It is clear that, however much the bones may have been water-worn before deposition on land, both they, and the adjacent shingle, must have been deposited there nearly about the same time. Tripoli stone, and other substances composed chiefly, if not entirely, of microscopic insects, may have been formed by the accumulation and cohesion of myriads of such minute crea- tures, swept together off" the land, like swarms of locusts, aggregated by^the rolling of the Avaves, agglutinated, deposited on the land, and afterwards heavily compressed. Or they may have been insects bred in water; such as those which Mr, Darwin calculated to amount to " one hundred thousand in a square inch of surface ;" while the sea was streaked with them for a great distance. J Microscopic objects such as these may have been killed by some gas rising from a volcano beneath ; then drawn together by mutual attraction, rolled over and * When * blown ' after putrefaction beg^an. ' t Those, for instance, of Blanco Bay, p. 112. I Darwin's Letters to Professor Henslow, printed for private distribu- tion among the members of the Cambridge Philosophical Society : in 183.5.