An illuminating exemplification of the use that may be made of the plays in the study of such problems has been given by Professor Edward Capps.[180] He showed that if chorus and actors be thought of as separated by a clearly marked line such as the edge of a ten-foot stage would afford, the action of the forty-four extant dramas requires the chorus alone to pass over this boundary at least sixty-eight times, the chorus and actors together nine times, and the actors alone thirty-nine times. Actors and chorus are repeatedly brought into the closest possible contact. For example, in Euripides’ _Iphigenia among the Taurians_, vss. 1068-70, Iphigenia appeals to each member of the chorus in turn, touching the hand of one and the chin and knees of another, begging for their help. [Illustration: FIG. 44.—Movements of the Actors in Aristophanes’ _Frogs_, vss. 1-460] Again, the incidents of many plays come into harmony with theatrical conditions only if we suppose that there was no stage. Perhaps the best and clearest illustration of this is afforded by Aristophanes’ _Frogs_ (405 B.C.). Xanthias and Dionysus, engaged in conversation, enter the orchestra at one of the side entrances (Fig. 44_a_). At vs. 35 the latter calls attention to the nearest of the three doors in the proscenium, saying: “I am already near this door where I must turn in.” It transpires that this is the house of Heracles (Fig. 44_b_), and Dionysus’ knock brings his brother in person to the door. From him they receive directions for their trip to the lower world—that first they will come to a large lake which they must cross in a tiny boat, then they will see perjurers, thieves, and criminals of the deepest dye, and finally will be received by happy bands of initiates (the chorus), who “dwell alongside the very road at the doors of Pluto” (vss. 162 f.). Scarcely have they left Heracles’ door when they behold a trundle-boat pushed from the opposite parodus into the orchestra (_CC′_) and hear Charon’s “Yo-heigh, Yo-ho” (vs. 180). He approaches the edge of the orchestra where they now stand, but when they prepare to embark Charon refuses to receive a slave on board and poor Xanthias is ordered to run around the lake (_C′C″D_; vs. 193). Meanwhile Dionysus and Charon direct their boat across the orchestra (_C′D_) to where, in the center of the front row of seats, the priest of Dionysus and other functionaries always sat (Fig. 45);[181] and from behind the scenes, to accompany their rowing, the choreutae sing a “frog” chorus as if from the bottom of the lake (vss. 209-69). Upon disembarking (at _D_) Dionysus calls for his slave and catches his faint reply as he comes into sight (!) from his “arduous” trip around the orchestra’s semicircumference. Xanthias now points out to his master the perjurers, etc., in the nearby audience (vs. 275). Presently they are badly frightened and Dionysus appeals to his priest, who is within arm’s length of him, to protect him (vs. 297).