It is just about this time that unmistakable knowledge of the Jews themselves, as a separate nationality of Syrians, is evidenced in extant Greek writers. Histories of the nearer and of the remote East, impressions of travel and concatenation of irresponsible gossip of all sorts had long been written by Greeks. Some of these may well have contained reference to the Jews. In the fifth century, Herodotus speaks of the “Syrians of Palestine” in connection with the rite of circumcision, which, he claims to know from the testimony of the Syrians themselves, was derived from Egypt.[80] However, he obviously writes at second hand, so that we have no means of knowing whether or not he refers to Jews. That he knew the name Ἰουδαῖοι is not likely, but the fact that his source was probably a literary one makes it possible to date the acquaintance of Greeks with the practice of circumcision in this region, and therefore perhaps with Jews, at least to the beginning of the fifth century B.C.E. The peculiar natural phenomena of the Dead Sea attracted the attention of travelers from very early times. Aristotle discusses it, and after him—no doubt before him, as well—the collectors of wonder-tales, of which we have so many later specimens. Interest in the Dead Sea, however, by no means implied interest in those who dwelt on its borders, and the story of the bituminous formation on the water and the curious manner in which it was collected could be and was told without so much as a mention of the name of Jews.[81] But they are mentioned, and for the first time in extant Greek writers, by the famous pupil and successor of Aristotle, Theophrastus of Lesbos. The passage does not occur in any one of the works of Theophrastus which we have in bulk, such as the Characters or the Natural History. It is a quotation made by the Neoplatonic philosopher Porphyrius, who wrote somewhere about 275 C. E. The quotation may, in accordance with ancient custom, be of substance rather than verbatim. Faulty memory may have further diminished its value for our purposes. When we add to these facts possible uncertainties in the transmission of the text of Porphyrius, we are in a fair way of realizing from what dubious material we must piece our knowledge together. The passage is in itself, except perhaps for one casual phrase, strangely unimportant, but as the earliest plain reference to Jews in a Greek writer it deserves citation in full: