When a small portion of a stratum is examined, such as the present case, it is impossible from inspection to determine, whether it owes its inclined position to the sinking or the raising of the ground; the stratum is changed from its original position, but whether this has been brought about by the raising of the one side, or the sinking of the other is not apparent from what then is seen. But unless we are to explain the appearance of strata above the level of the sea by a supposition which is that of the retreat of the ocean, a theory which this author has adopted, it is as impossible to explain the present appearance of horizontal strata as of those that are inclined. At the same time, if a power placed below the strata is to be employed for the purpose of raising them from the bottom of the sea, to the place in which we find them at present, it is impossible that this should be done without the fracture of those strata in certain places; and it is much more difficult to conceive this operation not to be attended with changing the natural horizontal position of strata, and thus leaving them in many places inclined, than otherwise by supposing that this internal power of the globe should elevate the strata without changing their original position. With this description of strata on the Rhine, we may compare that of M. Monnet respecting those which he found upon the Meuse, (Nouveau Voyage Minéralogique, etc. Journal Physique, Aoust, 1784.) Speaking of the schistus, or slate, he adds: «Mais ces petites veines nous donnent lieu de faire une observation importante; c'est qu'elles se présentent assez communement perpendiculaire, tandis que les grands bancs d'ardoises, ceux qu'on exploite, sont, comme nous l'avons dit, couchés sur une ligne de 15 à 20 degrés. J'ai parlé des montagnes de marbre qui sont derrière Givet, et de celles sur la quelle est situé Charlemont. J'ai fait voir que bien loin que les bancs de marbre, qui forment la montagne du Givet, soient horizontaux comme on seroit tenté de le croire, d'après les principes de quelques naturalistes systématiques, qui pensent que tous les bancs de pierres calcaires ne sauroient être autrement; j'ai fait voir, dis-je, que ces bancs sont presque perpendiculaire à l'horizon; et de plus, qu'ils sont tellement collés les uns contre les autres, qu'à peine on peut les distinguer.» The changed structure and position of the strata, now exemplified from the observations both of M. de Saussure and M. de Luc, observations made in a great extent from France to Germany, show the effects without the means by which those effects had been produced; and, in this case, it is by judging from certain principles of natural philosophy that the cause is discovered in the effect.