Cayster on the south. He331 names the Pactolos as a river rising on Mt. Tmolos and flowing into the Hermos. Hence it would appear that Theophrastus is mistaken about the name of the river in which touchstones were found. On the other hand, if the text is corrupt, he may originally have spoken of the river that rises on Mt. Tmolos. It is also possible that one of the other rivers rising on Mt. Tmolos may have been known in ancient times by the name of the mountain and that the text as we have it is correct. Though Theophrastus in this section and the two preceding ones does not give any name to the stone used in testing precious metals and their alloys, it should be noted that in section 4 he said that a stone of this kind was called ή Λυδη, and it seems clear from the name of the river mentioned here as the sole source of such stones that the name Lydian stone is to be understood. Owing to the ambiguity of the text in section 4, it is possible, however, that the name "Heraclean stone," which really refers to the lodestone, was also applied to the touchstone. An earlier Greek name for the touchstone was βάσανος,332 and this name may also have been current at the time of Theophrastus. At any rate, all three names, or derivations of them, were used by ancient authors later than Theophrastus. Sometimes later writers also refer to this stone without using any distinctive name. An example of this usage occurs in the thirty-eighth recipe of the Leyden Papyrus X. It is interesting to note that mineralogists now describe the kind of stone best suited for use as a touchstone by names that are based directly on the ancient Greek names. In English, for example, this kind of stone is called basanite or, alternatively, Lydian stone.333
47. They are smooth in nature and li\e pebbles. It is probable that the touchstones described by Theophrastus were simply rounded pieces of alluvial slate, since Boz Dagh, the ancient Mt. Tmolos, is comprised largely of gneiss and slate,334 and of these two rocks only the slate could have been used for touchstones. Though Theophrastus states that touchstones all came
331 XII, 3, 27; XIII, i, 23; XIII, 4, 5.
332 Pindar, Pythian Odes, X, 67; Aristotle, Historia Animalium, VIII, 12, 597B; Aristotle, De Coloribus, III, 793B; Theognis, 417.
333 Dana, System of Mineralogy, p. 189.
334 Pauly-Wissowa, Real-Encyclopadie (2) VI, pp. 1627-28.
