still others were watching the entertainment-and of that , there seemed to be a dazzling variety : on the gallery above , a band of minstrels was playing , while other minstrels were strolling about the floor entertaining smaller groups ; four jugglers in particolored costumes were tossing balls high into the air in the center of the room and exchanging them with each other ; while at the far end of the hall three acrobats hurtled into the air .