Possible Clues:

• Jump on from above
• Plightweight?
• Spring onto the one of 30 across under the piano
• Leap like a leopard
• It's bound to be followed by a blow that's light at last
• Land on it lightly at last
• Power a big cat found to spring
• Jump or spring down as on prey
• Bound to be like a predator and be light at last
• Spring (like cat)