Mr. Knight also says that the Greek name papuros, mentioned by Theophrastus, a contemporary of Aristotle and Alexander, was probably the Egyptian name of the reed with a Greek termination. It was also called biblos by Homer and Herodotus, whence our term bible. The term volumen, a scroll, indicates the early form of a book of bark, papyrus, skin, or parchment, as the term liber (Latin, a book, or the inner bark of a tree) does the use of the bark itself. Hence also our terms library and librarian. "Book" is also derived from the Danish word bog, the bark of the beech. Pliny quoting Varro, who preceded him some two centuries, asserts that before the invention of papyrus, the large leaves of certain plants were prepared so that they could be written upon. Hence originates our term "leaves" of a book which in the Latin form folium has also given us the modern term folio. When, however, the reed pen and the pencil brush and their kindred substances denominated colored liquids or inks, came into vogue, some material on which characters could be inscribed and preserved in the shape of continuous rolls for record and other uses became necessary. The papyrus plant seems to have met every requirement. It is a noteworthy fact that all information which can be derived from any source, specifically calls attention to papyrus and sometimes the inner barks of trees as being coexistent with pen and ink. Varro has been credited with many statements which in the light of investigation and discovery are proved to be incorrect. One of these is in effect that the use of papyrus was an incident pertaining to the expeditions of Alexander the Great. This assertion is not only contradicted by Pliny, the historian, who calls attention to "books of papyrus found in the tomb of Numa " (Numa Pompilius, the second king of Rome, B. C. 716-672,) but even at this late day many monuments of ancient papyri are still extant and belonging to periods more than a thousand years before Alexander's time. The real facts in respect to this matter are, that the introduction of the use of papyrus to nations beyond the limits of Egypt was an event that did not take place until after the reign of the first Macedonian sovereign of Egypt, Ptolemy Lagus (B. C. 323) when, in return for Greek literature, Egypt gave back her papyrus. Before this epoch the Greeks had been in the habit of employing such materials as linen, wax, bark and leaves for ordinary writing purposes, while their public records were inscribed on stone, brass, lead or other metals. Papyrus as then introduced into those western countries was the only substance for a long period employed for literary purposes. Parchment and vellum, which were adopted there as writing materials about two centuries later, were too costly to be used so long as papyrus was within reach.