Subclass 1/26: Testing static or dynamic balance of machines or structures (balancing rotary bowls of centrifuges B04B 9/14; apparatus characterised by the means for holding wheels or parts thereof B60B 30/00; determining stability factors of ships B63B; stabilising of aircraft B64C 17/00; control systems for balancing automatically in operation G05; balancing rotors of dynamo-electric machines H02K 15/16) Determining unbalance (G01M 1/3, G01M 1/38 take precedence) by oscillating or rotating the body to be tested with special adaptations for marking, e.g. by drilling