The equation which Tacitus gives of the German gods with Latin ones is still in daily use in the names of the days of the week. The Romans applied the names of the planets, which were the names of their own gods, to the days of the week as early as the first Christian century; and in Germany the days were called after the German gods supposed to answer to the Roman gods in question. Half Europe to this day calls the days of the week after the Roman, and the other half after the German gods. We give the Latin names with the modern French and over against them the English, in which the names of the German gods appear more clearly than in modern German:-- Dies Solis, the Sun's day=Sunday. (The French _Dimanche_ is from _Dominicus_, the Lord's Day.) Dies Lunae (Lundi)=Monday or Moon's day. Dies Martis (Mardi)=Tuesday, the day of Tiw or Ziu. Dies Mercurii (Mercredi)=Wednesday, the day of Wodan. Dies Jovis (Jeudi)=Thursday, the day of Thor. In German this is _Donnerstag_, the day of Donar=Thor. Dies Veneris (Vendredi)=Friday, the day of Freya. Dies Saturni retains the Latin god's name in our Saturday. (The French _Samedi_ is derived from Sabbath.) These Teutonic names for the days of the week are common to all the branches of Teutonic speech, and must have a high antiquity. They tell us what gods the Germans had in early times, and to what Roman gods these were believed to correspond; but it would be a vain endeavour to attempt to deduce from this, or indeed from any early information we possess on the subject, the origin and nature of these gods. From Grimm's laborious study of the question (_German Mythology_, vol. i.) we gather that it is a matter mainly of speculation what it was in Wodan that led the Romans to identify him with their Mercury. Thor, who is identified with Jupiter, was probably a sky-god, while Tiw or Ziu (whom etymology identifies with Zeus, not Mars) was a god of war, and Freya, like Venus, had to do with female beauty. We come to know more of these gods when we find them in the Eddas, but it is scarcely legitimate to fill in the South German gods of the first century from the North German gods of the same names of the eleventh or twelfth. We reserve, therefore, our description of the German gods till we come to the Northern mythology.