[4]

On open coast near where Challenger was lost: I know no reason for supposing these matters are not now collecting in the bottom of an open & not deep sea. (Character of coast regular & rather deep soundings, 60–100 fathoms 2 & 3 miles from shore. V. Chart) Every winter torrents must bring much vegetable matter from thickly wooded mountains, probably chiefly leaves. This position agrees with character of in Basins from rivers & natural positions

[4v]

chiefly red glassy scoriæ - could walk round base: not universal; could not climb up many parts, in James Isd. -Mem St Helena - All Trachytic. - Daubeny P. 171. Vol I. Humboldt

There is long discussion on Pumice & Obsidian: in the I Vol. Humb:

There is rather good abstract of Humboldt. S. American Geolog. in Daubeny. P. 349

Admirable little table showing long periods of great violence volcanic from Humboldt: Comparison P 361. Daubeny