Related Clues:

• Forces
• Nuclear and solar, e.g.
• Vigorous feelings
• Heat and electricity
• Do they have the vitality, that is to say, to be in the greens?
• Force them among the greens
• Vigorous exertions
• Vigorous efforts
• Vigorous qualities to put into one's work
• Efforts of heartless foes seizing empty Reichstag