350 ELEMENTS OF SCIENCE 



He was a Spaniard, and only twenty-five years old when 

 he came into power. In his reign the Roman Empire 

 attained its greatest extent. Through conquests over 

 the Parthians, it reached from the Caspian to the 

 Persian Gulf, while Dacia was also subdued and annexed. 

 Thus the empire never included either Bohemia or 

 Moravia, or Austro-Hungary between the Danube and 

 the Theiss, nor any part north of the Danube between 

 Pesth and Donauwerthe. 



With this emperor we enter upon the eventful second 

 century of the Christian era. His successor, Hadrian, 

 was a Roman by birth, who reigned from 117 to 138. 

 He had accompanied his predecessor in most of his 

 expeditions and subsequently visited almost all the 

 provinces of the empire. In England he built the well- 

 known wall to keep off the northern tribes. He had 

 hardly succeeded to power when the boundaries of the 

 empire began to recede, and he at once made peace with 

 the Parthians, and yielded up great part of his prede- 

 cessor's conquests over them. 



The next two emperors were the most celebrated of 

 all for their morality and piety. The first of these, who 

 had been adopted by Hadrian, was Antoninus Pius and 

 was the son of a Roman consul. He came into power 

 138 A.D., and reigned twenty-three years, leading a life 

 of most exemplary benevolence and temperance. His 

 only war was in England, wherein he extended the 

 Roman dominion, building a second wall to keep out the 

 unsubdued inhabitants of Scotland. He adopted his 

 successor, Marcus Aurelius, who espoused his unworthy 

 daughter Faustina. He succeeded to power 161 A.D., 

 and reigned nineteen years with the esteem and admira- 

 tion of his subjects. But many troubles took place 

 during his supremacy, and he had to exert the greatest 



