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Following The promontory on which the town stands: we first have a strange mass of vast angular fragments of various volcanic rocks (chiefly compact A) these are firmly cemented together: a little further we meet with (A) compact variety itself, some of the exterior layers are curvilinear; the great mass of angular fragments which occur & tilt in many place on the coast clearly overlie, directly the Lava or Basalt. — in some places this Breccia is so mingled with the lava, that I think it must have been involved in the lava. — The lava affects an angular cleavage, its surface is cellular. — it is occasionally truly vesicular (F). — at other times amygdaloid with lime. — As I have said, the common variety is the very compact sort (A). — Varieties passing into Pitchstone (B) (C) are nearly as abundant. —

(B) (C) (D) occurred close together, & passed into each other. — There is a red porphyritic kind (E). — which is found close to a black basalt with crystals of white feldspar. — Then other, pale colored less crystalline varieties (G). — But the most remarkable is the

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frequent passage of the hardest basalts into more or less pale clays or wackes. — Now these changes are not very gradual. — the basalt is at point of contact rather softer, & the wackes contains nodules of harder rock. The wacke shows a porphyritic structure. — Where a concretionary structure is present in the basalt it is found in the wacke. — Now these changes (H) take place apparently without any sort of order. —

transition lateral

masses of lava occur in the midst of the wacke & projects up at at different heights. — Hence from weathering during the upheaval of the land, abrupt masses stand out on the coast. — the connection of which with the surrounding land, at first much puzzled me. — Perhaps the wacke more commonly overlies the hard rock. —

I am do not know on what this lava lies, therefore its age is doubtful. — I have seen a bed of round volcanic pebbles separating two masses therefore there would seem to have been two currents; both superior & inferior was much mingled with great fragments. —

Above the lava in many places or more commonly the wacke

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(3)

there is a stratified substance, closely resembling wacke, abr & evidently resulting from its abrasion interstratified with blackish, laminated clay slate & a fine breccia. — This is covered by a thin bed of shingle of older rocks. — I have no doubt these beds correspond to those about Cheverea's creek. where to where the lava has not extended. — Fragments of volcanic rocks almost render it certain. —

I should have stated that the field of lava is difficult to be traced, perhaps this is owing to the weathering away of the wacke. — the wacke not having crystallized, cannot be owing to any difference in heat. —

In many places, a great mass of grey. hardened mud with small fragments overlies the field of lava

I should think perhaps poured out with lava. — the want of cleanliness & clearness of edges. Great contrast with S.Cruz lava. —

I found many small caves at about 8 12 10 feet

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[Huaso] Is^d half slate! —

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above water, in one of which there was much grey sand, with fragments of shells & cuts exactly like beach. — [sketch] structure of cavern. — Capt Williams. says about 4 feet. land has risen or water fallen during the last four years. — Knows by building a vessel.

Earthquake during this time not known to be coincident. —

Earthquake of Valparaiso not felt here no or v.versâ. — (Ashes fell in town from Osorno.) — Yet coast rising, some more general law. (Earthquake felt as far south as. [Isd of Wager]) —

I should previous to last 12 feet rise ground for many years stationary. —

[sketch] argument about pebbles retiring beaches

form of country

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5

On the beach facing the ship, we have a variety of volcanic rocks & fragmentary masses: some of the varieties have large nodules of Carb of lime. V (K^s) —

I may notice that with respect to the fragmentary masses, it is impossible to point out any line, where the mass was formed & united by melted lava & where the water alone has been this agent. — I found the lava overlying beds of black clay slate, yellowish clay, & fine breccia, which alternates in horizontal layers. — they precisely resembled what we have seen overlying the lava, in a short space these layers passed into a fragmentary mass. —

A pitchstone bed overlies a horizontal bed of wacke. —

On the road to Castro, all the rocks are volcanic, generally in the upper part a grey, laminated var earthy variety is present. —

I should have hardly known this excepting by its congeners with some crystalline vesicular rocks. hence we see lava at the higest part of this island: it was covered by vein of bright yellow clay (resulting from the wacke) & a cemented shingle of Cordilleras rocks. —

The coal mine, on the point, consists solely of rounded masses of the above butiminous matter, cordilleras pebbles & volcanic do. cemented in recent breccia; hence there must be a bed at bottom of the ocean: on a great fragmentary mass there are vertical tortuous veins of foliaceous carbinaceous mass; —

From description I think there must be a crater near Castro in centre of Island. — Reexamine wacke beneath pitchstone — At Castro beds of shells. — (Some say limestone on coast). — Superstitious bell rock. — Indian graves. —

The point of Chiloe, which forms the straits, contains some true disintegrated granite. — saw specimen

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Excellent coal of Estacillos & at some island in the archipelago

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Chiloe.

June-July. 1834