Mitkey, the mouse, wasn't Mitkey then. He was just another mouse, who lived behind the floorboards and plaster of the house of the great Herr Professor Oberburger, formerly of Vienna and Heidelberg; then a refugee from the excessive admiration of more powerful of his fellow-countrymen. The excessive admiration had concerned, not Herr Oberburger himself, but a certain gas which had been a by-product of an unsuccessful rocket fuel—which might have been a highly-successful something else. If, of co