As China went down, Rome came up.  Pan Chow died early in the reign of Trajan, the first great Roman conqueror since Julius Caesar; and only the Caspian Sea, and perhaps a few years, divided Trajan’s eastern outposts from the western outposts of the Hans.  We need not stay with this Spaniard longer than to note that here was a case where grand military abilities were of practical value:  Trajan used his to subserve the greatness of his statesmanship; only a general of the first water could have brought the army under the new constitutional regime.  The soldiers had been setting up Caesars ever since the night they pitched on old Claudius in his litter; now came a Caesar who could set the soldiers down.—­His nineteen years of sovereignty were followed by the twenty-one of Hadrian:  a very great emperor indeed; a master statesman, and queer mass of contradictions whose private life is much better uninquired into.  He was a mighty builder and splendid adorner of cities; all that remained unsystematized in the Augustan system, he reduced to perfect system and order.  His laws were excellent and humane; he introduced a special training for the Civil Service, which wrought enormous economies in public affairs:  officials were no longer to obtain their posts by imperial appointment, which might be wise or not, but because of their own tested efficiency for the work.—­Then came the golden twenty-three years of Antoninus Pius, from 138 to 161:  a time of peace and strength, with a wise and saintly emperor on the throne.  The flower Rome now was in perfect bloom:  an urbane, polished, and ordered civilization covered the whole expanse of the empire.  Hadrian had legislated for the down-trodden:  no longer had you power of life and death over your slaves; they were protected by the law like other men; you could not even treat them harshly.  True, there was slavery, —­a canker; and there were the gladiatorial games; we may feel piously superior if we like.  But there was much humanism also.  There was no proletariat perpetually on the verge of starvation, as in nineteenth and twentieth century Europe.  If we can look back now and say, There this, that, or the other sign of oncoming decay; the thing could not last;—­it will also be remarkably easy for us, two thousand years hence, to be just as wise about these present years ‘of grace.’  It is perhaps safe to say, —­as I think Gibbon says—­that there was greater happiness among a greater number then than there has been at any time in Christendom since.  Gibbon calculates that there were twice as many slaves as free citizens:  we do know that their number was immense,—­that it was not unusual for one man to own several thousand.  But they were well treated:  often highly educated; might become free with no insuperable difficulty:—­their position was perhaps comparable with that of slaves in Turkey now, who are insulted if you call them servants.  Gibbon estimates the population at a hundred and