With these facts in view, and considering the great size and elaboration of the ivory and gold statue of Athena, it is quite evident that the few years which elapsed between the commencement of the Parthenon and its dedication would have been amply occupied by this work alone,—and with the other duties incident to his position as superintendent of public works. More than this, we shall find it difficult to fix the time when he made some other of his statues, unless it was during these six years; and it would seem probable that at or about this time he must have been engaged upon the Athena Areia for the Platæans, or at least upon his chryselephantine statue of the celestial Venus for the Eleans. Before proceeding farther in this argument, it may be as well to give a glance at the artistic career of Phidias, and the various works executed by him, or assigned to him by different writers of an after-age. A good deal of discussion has arisen as to the age of Phidias at his death. The date of his birth is distinctly given by no one, and is purely a matter of conjecture. Thiersch, among others, supposes him to have been already an artist of some distinction in the 72·3 Olympiad, or about B. C. 490—the date of the battle of Marathon; and this opinion he founds chiefly on the fact that the Athena Promachos, as well as the group of statues at Delphi and the acrolith of Athena at Platæa made by him, were cast, according to Pausanias, from the tithe of the spoils taken from the Medes who disembarked at Marathon. Other writers suppose him to have been born at about the date of the battle of Marathon, and that the statues executed by him out of the spoils were made some twenty-five years later. Mr. Philip Smith, in his “Dictionary of Biography and Mythology,” taking this view, places his birth in the 73d Olympiad; and Müller is of the same opinion. Dr. Brunn, on the contrary, thinks it probable that he was born about the 70th Olympiad, and Welcker and Preller agree substantially with him. According to the supposition of Thiersch, placing his birth at 67·2 Olympiad, or B. C. 510, he would have been twenty years of age at the battle of Marathon (B. C. 490), seventy-two years of age when he finished the chryselephantine statue of Athena in the Parthenon in 85·1 Olympiad (B. C. 438), and seventy-seven years of age when he finished the chryselephantine statue of Zeus at Olympia in 87·3 Olympiad (B. C. 433). This, if we suppose that five years elapsed after the battle of Marathon before the group of statues at Delphi was executed, would make Phidias twenty-five years old when he made them.