Forty-five tree rings (1881-1925) were taken from a white spruce grown near Campbell River in Mackenzie Delta, Canada, for the measurement of carbon-14 activity variation. Because the rings were narrow, two and sometimes three rings were combined to yield a total of 21 specimens. The carbon-14 content in these specimens was measured with a liquid scintillation-PM tube counter system of the History Department of Peking University. The data points exhibit a ten percent variation, anti-correlated with sunspot numbers. The physical implication is discussed. -- AATA