It would be tedious to multiply testimony on a point so universally understood. As for the other half of this fact, that even the so-called "youngest" rocks may be metamorphic and crystalline just as well as the "oldest," it also is now a recognized commonplace of science. Dana[16] says that as early as 1833 Lyell taught this as a general truth applicable to "all the formations from the earliest to the latest." The first reference I can find to any disproof of this old fable of Werner's, that only certain kinds of rock are to be found next to the "Primitive" or Archaean, is in the observations of Studer and Beaumont in the Alps, (1826-28), who found "relatively young" fossils in crystalline schists, which, as Zittel says, "was a very great blow to the geologists who upheld the hypothesis of the Archaean or pre-Cambrian age of all gneisses and schists." James Geikie, doubtless referring to the same series of rocks, tells us that:-- "In the central Alps of Switzerland, some of the Eocene strata are so highly metamorphosed that they closely resemble some of the most ancient deposits of the globe, consisting, as they do, of crystalline rocks, marble, quartz-rock, mica schist, and gneiss."[17] Hence we need not be surprised at the following statement of the situation by Zittel.[18] "The last fifteen years of the nineteenth century witnessed very great advances in our knowledge of rock-deformation and metamorphism. =It has been found that there is no geological epoch whose sedimentary deposits have been wholly safeguarded from metamorphic changes=, and, as this broad fact has come to be realized, it has proved most unsettling, and has necessitated a revision of the stratigraphy of many districts in the light of new possibilities. The newer researches scarcely recognize any theory; they are directed rather to the empirical method of obtaining all possible information regarding microscopic and field evidences of the passage from metamorphic to igneous rocks, and from metamorphic to sedimentary rocks."