When Perceval was whole, he departed from the castle of the Queen of
the Golden Circlet, all of whose land was at his commandment. The Queen
told him that she would keep the Golden Circlet until he should will
otherwise, and in such sort he left it there, for he would not carry it
with him, sith that he knew not whitherward he might turn. The history
telleth us that he rode on until one day he came to the Castle of
Copper. Within the castle were a number of folk that worshipped the
bull of copper and believed not in any other God. The bull of copper
was in the midst of the castle upon four columns of copper, and
bellowed so loud at all hours of the day that it was heard for a league
all round about, and there was an evil spirit within that gave answers
concerning whatsoever any should ask of it.