348 A Short History of The World INCIDENT IN THE DAYS OF THE SLAVE IRADE {From a ^rtnt after Morlnnd in the British Mitsevtri) the plain logic of the new situation asserted itself more clearly. Human beings were no longer wanted as a source of mere indis- criminated power. What could be done mechanically by a human being could be done faster and better by a machine. The human being was needed now pnly where choice and intelligence had to' be exercised. Human beings were wanted only as human beings. The drudge, on whom all the previous civilizations had rested, the creature of mere obedience, the man whose brains were superfluous,' had become unnecessary to the welfare of mankind. This was as true of such ancient industries as agriculture and mining as it was of the newest metallurgical processes. For ploughing, sowing, and harvesting, swift machines came forward to do the work of scores of men. The Roman civilization was built upon cheap and degraded human beings ; modern civilization is being rebuilt upon cheap mechanical power. For a hundred years power has been getting cheaper and labour dearer. If for a generation or so machinery has had to wait its turn in the mine, it is simply because for a time men were cheaper than machinery.