But it is nevertheless true, that this metaphorical locution recalls also one of the uses made of that fat substance, which was for a long while employed, like oil, to soften and refresh the limbs. Indulgent reader, excuse this episode upon a ground which we ought not to touch, and let us re-enter the kitchen. The Greeks, who understood many things, and knew them so well, passed over several centuries without once thinking that the milk of their ewes and cows contained a food already well-known by several barbarous nations. Aristotle mentions the serous part of milk, and cheese;[XVIII-24] but he hardly suspects the existence of butter, which he describes but very imperfectly as a liquid oil.[XVIII-25] Antecedent to him, Hippocrates never thought of it, except as a foreign remedy which Asia supplied to Greece.[XVIII-26] It was only fifty years after Aristotle that it began to be noticed as an aliment. The Greeks, in imitation of the Parthians and Scythians, who used to send it to them, had it served upon their tables, and called it at first “oil of milk,”[XVIII-27] and later, _bouturos_, “cow cheese,” probably on account of the quantity made from the milk of that animal.[XVIII-28] The Germans, according to Beckmann, taught the Romans how to make butter, but they never employed it otherwise than as a remedy in Italy. It is certain that in the time of Pliny it had hardly been heard of at Rome,[XVIII-29] and that, according to this writer, the barbarians only--that is to say, those who were unfortunate enough not to be either Greeks or Romans--made their food of it.[XVIII-30] Towards the year 175 of the Christian era, Galen then placed butter only among the therapeutic agents useful in medicine.[XVIII-31] However, more than a century before him, Dioscorides wished it to be noticed that fresh butter made of ewes’ or goats’ milk was served at meals instead of oil, and that it took the place of fat in making pastry.[XVIII-32] Herodotus has preserved some interesting details on the manipulation of butter among the Scythians. They received the milk in large pails, and beat it for a long time to separate the most delicate part, and appointed for this labour those enemies whom the fortune of war delivered into their hands. These unhappy creatures were deprived of sight, which prevented their escape.[XVIII-33] The Romans set about making butter as we do. Pliny says: “Butter is made from milk, and this aliment, so much sought after by barbarous nations, distinguished the rich from the common people. It is obtained principally from cows’ milk; that from ewes is the fattest. Goats also supply some. It is produced by agitating the milk in long vessels with a narrow opening. A little water is added.”[XVIII-34]