Father Caulin Descrip.

Corografica page 25, in speaking of resins found in the forests of Cumana, makes a just distinction between the Draco de la Sierra de Unare, which has pinnate leaves (Pterocarpus Draco), and the Draco de la Sierra de Paria, with entire and hairy leaves.

The latter is the Croton sanguifluum of Cumanacoa, Caripe, and Cariaco. ) The red and astringent juice of this plant is employed to strengthen the gums. The Indians recognize the species by the smell, and more particularly by chewing the woody fibres. Two natives, to whom the same wood was given to chew, pronounced without hesitation the same name. We could avail ourselves but little of the sagacity of our guides, for how could we procure leaves, flowers, and fruits growing on trunks, the branches of which commence at fifty or sixty feet high? We were struck at finding in this hollow the bark of trees, and even the soil, covered with moss* and lichens. (* Real musci frondosi. We also found, besides a small Boletus stipitatus, of a snow-white colour, the Boletus igniarius, and the Lycoperdon stellatum of Europe. I had found this last only in very dry places in Germany and Poland.) The cryptogamous plants are here as common as in northern countries. Their growth is favoured by the moisture of the air, and the absence of the direct rays of the sun. Nevertheless the temperature is generally at 25 degrees in the day, and 19 degrees at night.

The rocks which bound the crevice of Cuchivano are perpendicular like walls, and are of the same calcareous formation which we observed the whole way from Punta Delgada. It is here a blackish grey, of compact fracture, tending sometimes towards the sandy fracture, and crossed by small veins of white carbonated lime. In these characteristic marks we thought we discovered the alpine limestone of Switzerland and the Tyrol, of which the colour is always deep, though in a less degree than that of the transition limestone.* (* Escher, in the Alpina volume 4 page 340.) The first of these formations constitutes the Cuchivano, the nucleus of the Imposible, and in general the whole group of the mountains of New Andalusia. I saw no petrifactions in it; but the inhabitants assert that considerable masses of shells are found at great heights. The same phenomenon occurs in the country about Salzburg.* (* In Switzerland, the solitary beds of shells, at the height of from 1300 to 2000 toises (in the Jungfrauhorn, the Dent de Morcle, and the Dent du Midi), belong to transition limestone.) At the Cuchivano the alpine limestone contains beds of marly clay,* (*Mergelschiefer.) three or four toises thick; and this geological fact proves on the one hand the identity of the alpenkalkstein with the zechstein of Thuringia, and on the other the affinity of formation existing between the alpine limestone and that of the Jura.* (* The Jura and the Alpine limestone are kindred formations, and they are sometimes difficult to be distinguished, where they lie immediately one upon another, as in the Apennines. The alpine limestone and the zechstein, famous among the geologists of Freyberg, are identical formations. This identity, which I noticed in the year 1793 (Uber die Grubenwetter), is a geological fact the more interesting, as it seems to unite the northern European formations to those of the central chain. It is known that the zechstein is situated between the muriatiferous gypsum and the conglomerate (ancient sandstone); or where there is no muriatiferous gypsum, between the slaty sandstone with roestones (buntesandstein, Wern.), and the conglomerate or ancient sandstone. It contains strata of schistous and coppery marl (bituminoce mergel and kupferschiefer) which form an important object in the working of mines at Mansfeld in Saxony, near Riegelsdorf in Hesse, and at Hasel and Prausnitz, in Silesia. In the southern part of Bavaria (Oberbaiern), I saw the alpine limestone, containing these same strata of schistous clay and marl, which, though thinner, whiter, and especially more frequent, characterize the limestone of Jura. Respecting the slates of Blattenberg, in the canton of Glaris which some mineralogists, because of their numerous impressions of fish, have long mistaken for the cupreous slates of Mansfeld, they belong, according to M. von Buch, to a real transition formation. All these geological data tend to prove that strata of marl, more or less mixed with carbon, are to be found in the limestone of Jura, in the alpine limestone, and in the transition schists. The mixture of carbon, sulphuretted iron, and copper, appears to me to augment with the relative antiquity of the formations.) The strata of marl effervesce with acids, though silex and alumina predominate in them: they are strongly impregnated with carbon, and sometimes blacken the hands, like a real vitriolic schistus. The supposed gold mine of Cuchivano, which was the object of our examination, is nothing but an excavation cut into one of those black strata of marl, which contain pyrites in abundance. The excavation is on the right bank of the river Juagua, and must be approached with caution, because the torrent there is more than eight feet deep. The sulphurous pyrites are found, some massive, and others crystallized and disseminated in the rock; their colour, of a very clear golden yellow, does not indicate that they contain copper. They are mixed with fibrous sulphuret of iron,* (* Haarkies.) and nodules of swinestone, or fetid carbonate of lime. The marly stratum crosses the torrent; and, as the water washes out metallic grains, the people imagine, on account of the brilliancy of the pyrites, that the torrent bears down gold. It is reported that, after the great earthquake which took place in 1766, the waters of the Juagua were so charged with gold that "men who came from a great distance, and whose country was unknown," established washing-places on the spot. They disappeared during the night, after having collected a great quantity of gold. It would be needless to show that this is a fable. Pyrites dispersed in quartzose veins, crossing the mica-slate, are often auriferous, no doubt; but no analogous fact leads to the supposition that the sulphuretted iron which is found in the schistose marls of the alpine limestone, contains gold.

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