Explanation: Theseus fights the Minotaur.In the meanwhile the little child at Troezen on the other side of the sea had grown to be a man. His name, Theseus, was in everybody's mouth, for he had done great deeds of daring; and at last he had come to Athens to find his father, King Aegeus, who had never heard whether he was alive or dead; and when the youth had made himself known, the king had welcomed him to his home and all the people were glad because so noble a prince had come to dwell among them and, in time, to rule over their city.
The first two sentences are establishing characteristic shared by both petroleum and coal. The word "however" is used to contrast the similarities already presented with the differences that will be stated in the following sentences.