Possible Clues:

• Tempers
• Makes hard queen say less occasionally
• Tempers, as metal
• Heats and then slowly cools to temper
• Toughens, as metal
• Tempers turning hot and cold
• Discard of Henry's, a lass having lost heart, toughens up
• Tempers, in a way
• Heats, as glass
• Treats steel