[190] H. Ritter (Geschichte der Philosophie, ch. vi, p. 243) has some good remarks on the difficulty and obscurity of the early Greek prose-writers, in reference to the darkness of expression and meaning universally charged upon the philosopher Herakleitus. Of that splendid genius in sculpture and architecture, which shone forth in Greece after the Persian invasion, the first lineaments only are discoverable between 600-560 B. C., in Corinth, Ægina, Samos, Chios, Ephesus, etc.,—enough, however, to give evidence of improvement and progress. Glaukus of Chios is said to have discovered the art of welding iron, and Rhœkus, or his son Theodôrus of Samos, the art of casting copper or brass in a mould: both these discoveries, as far as can be made out, appear to date a little before 600 B. C.[191] The primitive memorial, erected in honor of a god, did not even pretend to be an image, but was often nothing more than a pillar, a board, a shapeless stone, a post, etc., fixed so as to mark and consecrate the locality, and receiving from the neighborhood respectful care and decoration, as well as worship. Sometimes there was a real statue, though of the rudest character, carved in wood; and the families of carvers,—who, from father to son, exercised this profession, represented in Attica by the name of Dædalus, and in the Ægina by the name of Smilis,—adhered long, with strict exactness, to the consecrated type of each particular god. Gradually, the wish grew up to change the material, as well as to correct the rudeness, of such primitive idols; sometimes the original wood was retained as the material, but covered in part with ivory or gold,—in other cases, marble or metal was substituted. Dipœnos and Skyllis of Krête acquired renown as workers in marble, about the 50th Olympiad (580 B. C.), and from them downwards a series of names may be traced, more or less distinguished; moreover, it seems about the same period that the earliest temple-offerings, in works of art, properly so called, commence,—the golden statue of Zeus, and the large carved chest, dedicated by the Kypselids of Corinth at Olympia.[192] The pious associations, however, connected with the old type were so strong, that the hand of the artist was greatly restrained in dealing with statues of the gods. It was in statues of men, especially in those of the victors at Olympia and other sacred games, that genuine ideas of beauty were first aimed at and in part attained, from whence they passed afterwards to the statues of the gods. Such statues of the athletes seem to commence somewhere between Olympiad 53-58, (568-548 B. C.). [191] See O. Müller, Archäologie der Kunst, sect. 61; Sillig. Catalogus Artificium,—under Theodôrus and Teleklês.