Abraham Gottlob Werner (1749-1817) was for many years the most famous of the professors in the Freiberg School of Mines. His Neptunist school may have retarded geological thought, but his inspiring teaching and his earnest effort to classify all data did even more to advance it.

The unexpected observation which I made last summer at the hill of Scheibenberg, well known as basaltic, ought to be infinitely important because of the relations of the basalt with the rocks on which it rests.* It should be considered impartially by every geognost observer, especially at a time when the nature and origin of basalt provoke the inquiries of savants and hold their attention.

Earlier I had noticed from a distance, a great, white mine dump near the summit of this basaltic mountain, which is situated a scant quarter league and almost due south from the little town of Scheibenberg. On inquiry, I was told that it was the dump of a sand pit that had served the needs of the town since it was founded. A mine of sand at the summit of a basaltic mountain seemed a very singular thing to me. So it was my first care, on climbing this mountain to make a mineralogic examination, to direct my attention to this sand pit.

I had already seen from afar that the hill, or rather its summit, was cut in one place so that I would find a nearly perpendicular section there. Thus I would be able to reconnoiter the interior of the basaltic mountain a little. It will be seen that I was not mistaken in my opinion. Nevertheless I thought that it was only a bank of sand which surrounded the foot of the basaltic summit, in

* That is, its relations with the gneiss on which the basalt and the beds which form its base are found here, not as the product of an eruption and of a volcanic heaping, but always as a precipitation by the humid way. 138



the way it generally was believed then that the sand and clay were deposited at Pohlberg, near Annaberg, where, as is known, these fossils [fragments of basalt] were extracted in great quantity.

But how surprised I was to see, at the first glance on arriving, first, at the base, a thick bank of quartzose sand, then above, a bed of clay, finally a bed of argillaceous stone called wacke, and resting on this last, the basaltl I saw the first three beds bury themselves nearly horizontally under the basalt and thus form its base, the sand becoming finer above, more argillaceous, and finally changing into true clay, as the clay was converted into wacke in its upper part, and finally the wacke into basalt. In a word, I found here a perfect transition from pure sand to argillaceous sand, from the latter to sandy clay and from the sandy clay by many gradations to the fat clay, to the wacke, and finally to the basalt.

At this sight, I was led at once and irresistibly to think (as would, without doubt, any impartial connoisseur, struck by the consequences of this phenomenon)--I was, I say, irresistibly led to the following ideas. This basalt, this wacke, this clay, and this sand are of one and the same formation. They are all the result of a precipitation by the humid way in one and the same submersion of this country. The waters which covered it then transported first the sand, then deposited the clay, and gradually changed their precipitation into wacke and finally into true basalt.

Space does not permit me to enter into more detail on this great and important observation, but I shall certainly give a more ample description of it soon in one of our journals. Now what will the large party among our mineralogists who are very much biased in favor of the volcanic origin of the basalts say?

I shall add some further short remarks to this observation. The | basalt presents a considerable section here, but it is nearly perpendicular and it is divided into columns. The gaps which separate these basaltic columns descend into the wacke and penetrate in some places across the bed at the base. The wacke has almost a schistose structure. One cannot see the base of the bed of sand, as it is covered by the dump, but one observes that it becomes coarser towards the bottom and changes into true gravel or pebbly sand. The gneiss that constitutes the country rock of all this region is found immediately below the sand dump.

All true veins were originally, and of necessity, rents open in their upper part, which have afterwards filled up from above.

Rents may be produced by many different causes. Mountains have been formed by a successive accumulation of different beds or layers placed or heaped upon one another. The mass of these beds was at first wet, and possessed little solidity, so that when the accumulation of matter had attained a certain height, the mass of the mountain yielded to its weight, and must consequently have sunk and cracked. As the waters which formerly assisted in supporting the mass of the mountain began to lower their level; these masses then lost their former support, yielded to the action of their weight, and began to separate and be detached from the rest of the mountain, falling to the free side, or that where the least resistance was opposed. The shrinking of the mass of the mountain, produced by desiccation, and still more by earthquakes, and other similar causes may also have contributed to the formation of rents.

The same precipitation, which in the humid way formed the strata and beds of rocks, (also the minerals contained in these rocks), furnished and produced the substance of veins; this took place during the time, when the solution from which the precipitate was formed, covered the already existing rents, which were as yet wholely or in part empty, and open in their upper part.

Veins (whether considered as rents, or as the substance constituting the vein) have been produced at very different times, and the antiquity or relative age of each can be easily assigned.

The distinguishing characteristics for the relative age of veins, and their substances, are the following:

1. Every vein which intersects another, is newer than the one traversed, and is of later formation than all those which it traverses; of course, the oldest vein is traversed by all those that are of a posterior formation, and the newer veins always cross those that are older.

When two veins cross, one of them without suffering any derangement or interruption traverses the other; this last is interrupted and cut across through its whole thickness by the former. . . .T his crossing of veins is of great importance, . . . yet, till now, it has always escaped the observation of mineralogists.


2. The middle part of veins is commonly of later formation than that portion which Is nearest their walls; and what we find in the upper part of a vein is newer than what we meet with in the lower part.

3. In a specimen composed of different minerals, the superimposed portion Is always of newer formation than that on which it rests, which is of course older.

In recapitulating the state of our present knowledge, it is obvious I that we know with certainty, that the flotz and primitive mountains have been produced by a series of precipitations and depositions formed in succession; that they took place from water which covered the globe, existing always more or less generally, and containing the different substances which have been produced from them. We are also certain that the fossils [minerals] which constitute the beds and strata of mountains were dissolved in this universal water and were precipitated from it: consequently the metals and minerals found in the primitive rocks, and in the beds of flotz mountains, were also contained in this universal solvent, that they also were formed from it by precipitation. We are still farther certain, that, at different periods, different fossils have been formed from it, at one time earth, at another metallic minerals, at a third time other fossils. We know too, from the position of these fossils, one above another, to determine with the utmost precision, which are the oldest, and which the newest precipitates. We are also convinced, that the solid mass of our globe has been produced by a series of precipitations formed in succession, (in the humid way).... The precipitates which formed the beds of mountains have, of necessity, deposited on the bottom of the general reservoir solid and compact materials; whilst the matter which composed the greater part of the mass of veins, being deposited by degrees on their walls, has there formed druses: Afterwards, minerals of different natures have been successively deposited upon one another.

. . . The geognost, who is possessed of the necessary knowledge of chemistry, and consequently of the impossibility of one elementary substance being transmuted into another, will see that there are only two ways in which the following question can be answered. At what time the metallic, earthy and other substances, which were, and still are in part, contained in the general solution; at what time, I say, have these substances entered into the general solution? It may be answered, either that these substances have altogether, and from the beginning, been contained in the universal solvent, or that they may have been introduced from time to time . . ., and if we admit the first answer, it is not possible to understand . . . why successive depositions should have been formed of so different a nature. Thus, it is not possible to conceive, why, in a mountain of gneiss, the strata of this rock should alternate many times with beds, in some instances, of limestone, sometimes of hornblende, lead-glance, and other metallic minerals: sometimes of magnetic ironstone, quartz, feldspar, etc.; all of which are essentially different from gneiss: sometimes also of limestone, clay, marl, lead-glance with calamine, chalk and flint; and this perhaps for more than a hundred times.... It is therefore most probable, that at different periods the universal solvent contained mixtures as various as, the different precipitates; and that the universal waters held in solution at one time one substance, at another, another.

From what has been said in this section, it must be obvious that the natural history of veins cannot be thoroughly understood without a knowledge of the primitive and fl6tz rocks, as well as their mode of formation.... In studying more particularly the different rock formations, we must begin with the newest, which are the alluvial; and from these, ascend successively to the most ancient. From the alluvial we pass to the newest flotz mountains, and so on through the transition to the oldest primitive mountains.