as soon as jack had read this he seized the trumpet and blew a shrill blast , which made the gates fly open and the very castle itself tremble . the giant and the conjurer now knew that their wicked course was at an end , and they stood biting their thumbs and shaking with fear . jack , with his sword of sharpness , soon killed the giant , and the magician was then carried away by a whirlwind ; and every knight and beautiful lady who had been changed into birds and beasts returned to their proper shapes . the castle vanished away like smoke , and the head of the giant galligantus was then sent to king arthur .
to cause the giant 's overthrow .
why did jack blow the trumpet ?
why did jack blow the trumpet ?