From these and a few more hints we may draw some conclusions as to the dates when the various books that make up the _Description of Greece_ were written. In the seventh book Pausanias tells us that his description of Athens was finished before Herodes Atticus built the Music Hall in memory of his wife Regilla. As Regilla appears to have died in 160 or 161 A.D. and the Music Hall was probably built soon afterwards, we may suppose that Pausanias had finished his first book by 160 or 161 A.D. at latest. There is, indeed, some ground for holding that both the first and the second book were composed much earlier. For in the second book Pausanias mentions a number of buildings which had been erected in his own lifetime by a Roman senator Antoninus in the sanctuary of Aesculapius at Epidaurus. If, as seems not improbable, the Roman senator was no other than the Antoninus who afterwards reigned as Antoninus Pius, we should naturally infer that the second book was published in the reign of Hadrian, that is, not later than 138 A.D., the year when Hadrian died and Antoninus succeeded him on the throne. With this it would agree that no emperor later than Hadrian is mentioned in the first or second book, or indeed in any book before the eighth. Little weight, however, can be attached to this circumstance, for in the fifth book Hadrian is the last emperor mentioned although that book was written, as we have seen, in the reign of Marcus Aurelius, thirty-six years after Hadrian’s death. A much later date has been assigned to the second book by Mr. W. Gurlitt in his valuable monograph on Pausanias. He points out that when Pausanias wrote it the sanctuary of Aesculapius at Smyrna had already been founded, and that if Masson’s chronology of the life of the rhetorician Aristides is right the sanctuary was still unfinished in 165 A.D. Hence Mr. Gurlitt concludes that the second book of Pausanias was written after 165 A.D. Even the first book, according to him, must be dated not earlier than 143 A.D. His reason is that when Pausanias wrote this book the stadium at Athens had already been rebuilt of white marble by Herodes Atticus, and that the reconstruction cannot, if Professor C. Wachsmuth is right, have been begun before 143 A.D. or a little earlier. With regard to the other books, the evidence, scanty as it is, is less conflicting. The fifth book, as we have seen, was composed in the year 174 A.D. The eighth book, in which mention is made of the victory of Marcus Antoninus over the Germans, must have been written after 166 A.D., the year when the German war broke out, and may have been written in or after 176 A.D., the year in which the emperor celebrated a triumph for his success. In the tenth book occurs the reference to the inroad of the Costobocs; hence the book was written between 166 and 180 A.D. Further, the references which Pausanias makes both forwards and backwards to the several parts of his work show that