It was upon such evidence as this that the “Apoxyomenus” was attributed to Lysippus. Practically all the well-known and frequently copied sculptures are attributed to the famous sculptors of antiquity upon similar grounds. In recent years, however, the archæologists have sought to introduce a supplementary method whereby the authorship of well-known sculptures may be verified. The method depends upon the minute examination of pieces of sculpture and the tabulation of their technical peculiarities. The eye or the ear, the nostril or the chin of a statue, and especially of a Greek original, speaks volumes to the scientific critic. Aided by a collection of prints, he arranges sculptures from any of the European collections into classes. The hint of a date enables him provisionally to associate a class with a well-known craftsman, and the identification of the authorship of masterpieces begins. Criticism of this kind looms largely in the literature of sculpture in these days. Even the amateur who is interested in art rather than archæology must, therefore, have a clear idea of the type of evidence leading to the ascription of well-known sculptures to particular artists. Almost any famous work would serve to illustrate this. Critical struggles, for instance, have waged around the “Venus of Milo.” Is it a fourth-century work, or can it be roughly dated at 150 B.C.? We have also referred to the critical mystery surrounding the authorship of the “Niobides.” We, however, choose for the purpose of illustrating our point, two famous works now in the Vatican—“The Ares Ludovisi” and the “Meleager.” Both are generally acknowledged to be copies of fourth-century sculptures of the finest quality. Neither possesses the strongly marked characteristics of the style of Praxiteles; nor do they resemble the “Apoxyomenus.” Are they then to be ascribed to Scopas? That is the critical problem. The “Ares” depicts the war-god as a youth. This is a fourth-century variation from the robust, bearded, and fully armed type of an earlier period. Ares is pondering fresh feats of arms. Or may be, as the Roman copyist suggests by the introduction of the tiny Eros, he is solving some deep amatory problem set him by Aphrodite. At first sight the “Ares” seems to be by a sculptor who has imbibed some of the spirit of both Scopas and Praxiteles. The sentiment strikes us as Praxitelean, the expression rather suggests Scopas. Leubke, noting the length of the limbs, says that the “Ares Ludovisi” reminds him of the style of Lysippus. Dr. Waldstein, however, will have none of this. He insists upon the claims of Scopas. To Dr. Waldstein, the overhanging brow which gives the pensive expression to the “Apoxyomenus” is _the_ characteristic of Lysippus. Its absence compels him to refer the “Ares” to Scopas. It all depends upon a wrinkle. Needless to say, we do not propose to decide where doctors disagree.