A null result was obtained for the weight change of a right-spinning gyroscope, contradicting the results recently reported by Hayasaka and Takeuchi. No weight change could be observed under a variety of spin directions for rotational frequencies between 0 and 2.2×${10}^4$ rpm. Our limit of -0.025±0.07 mg is more than 2 orders of magnitude smaller than the effect reported by Hayasaka and Takeuchi.

• Received 20 February 1990

DOI:https://doi.org/10.1103/PhysRevLett.64.2115