Windmills; wind-operated machines for generating power and parts and accessories therefor; wind turbines and parts and accessories therefor; mill towers, housings and masts for use in providing a supporting structure for windmills; windmill parts and accessories, namely, blades, blade hubs, machine beds, rotation devices, yaw rings and gears; pitch control devices for setting the pitch of wings, namely, blades, brakes and braking devices, all being parts and components of windmills; main shafts, namely, CAM shafts and shafts for pumps; universal joints and transmission cases being parts of windmills; clutches for machines and electric generators