Undergoes in
proportion to its progress, will be to substitute provisionally in the
description of formations, for the systematic names of red sandstone,
variegated sandstone, zechstein and Jura limestone, names derived from
American localities, as sandstone of the Llanos, limestone of
Cumanacoa and Caripe, and to separate the enumeration of facts
relative to the superposition of soils, from the discussion on the
analogy of those soils with those of the Old World.*
(* Positive geography being nothing but a question of the series or
succession (either simple or periodical) of certain terms represented
by the formations, it may be necessary, in order to understand the
discussions contained in the third section of this memoir, to
enumerate succinctly the table of formations considered in the most
general point of view.
1. Strata commonly called Primitive; granite, gneiss and mica-slate
(or gneiss oscillating between granite and mica-slate); very little
primitive clay-slate; weisstein with serpentine; granite with
disseminated amphibole; amphibolic slate; veins and small layers of
greenstone.
2. Transition strata, composed of fragmentary rocks (grauwacke),
calcareous slate and greenstone, earliest remains of organized
existence: bamboos, madrepores, producta, trilobites, orthoceratites,
evamphalites). Complex and parallel formations; (a) Alternate beds of
grey and stratified limestone, anthracitic mica-slate, anhydrous
gypsum and grauwacke; (b) clay-slate, black limestone, grauwacke with
greenstone, syenite, transition-granite and porphyries with a base of
compact felspar; (c) Euphotides, sometimes pure and covered with
jasper, sometimes mixed with amphibole, hyperstein and grey limestone;
(d) Pyroxenic porphyries with amygdaloides and zirconian syenites.
