16 - Book 13, Chapters 10 - 27: The trees of Syria: the pistacia, the cottana, the damascena and the myma; the cedar; the terebinth; the sumach tree; the trees of Egypt; the fig-tree of Alexandria; the fig tree of Cyprus; the carob tree; the Persian tree; the cucus; the Egyptian thorn; nine kinds of gum; the sarcocolla; the papyrus; the use of paper; when it was first invented; the mode of making paper; the nine different kinds of paper; the mode of testing the goodness of paper; the peculiar defects in paper; the paste used in the preparation of paper; the books of Numa