"These words were reported to the king, and he, being unable to credit them, ordered the chiefs to be brought before him. Having questioned them on the subject, they replied that all the wheat in the world would be insufficient to make up the quantity. He ordered them to prove what they said, and, by a series of multiplications and reckonings, they demonstrated to him that such was the fact. "On this, the king said to Sissah: 'Your ingenuity in imagining such a request is yet more admirable than your talent in inventing the game of chess.'" Ibn Khallikan was at pains to investigate the matter. Having, he says, "met one of the accountants employed at Alexandria, I received from him a demonstration which convinced me that the declaration was true. He placed before me a sheet of paper in which he had doubled the numbers up to the sixteenth square, and obtained thirty-two thousand seven hundred and sixty-eight grains. 'Now,' said he, 'let us consider this quantity to be the contents of a pint measure, and this I know by experiment to be true'--these are the accountant's words, so let him bear the responsibility--'then let the pint be doubled in the seventeenth square, and so on progressively. In the twentieth square it will become a waiba (peck), the waibas will then become an irdabb (bushel), and in the fortieth square we shall have one hundred and seventy-four thousand seven hundred and sixty-two irdabbs. Let us suppose this to be the contents of a corn store, and no corn store contains more than that; then in the fiftieth square we shall have the contents of one thousand and twenty-four stores; suppose these to be situated in one city--and no city can have more than that number of stores or even so many--we shall then find that the sixty-fourth and last square gives sixteen thousand three hundred and eighty-four cities. Now, you know that there is not in the world a greater number of cities than that, for geometry informs us that the circumference of the globe is eight thousand parasangs; so that, if the end of a cord were laid on any part of the earth, and the cord passed round it till both ends met, we should find the length of the cord to be twenty-four thousand miles, which is equal to eight thousand parasangs.' This demonstration is decisive and indubitable."