Positive correlations of magnetic pulsation amplitude with solar wind speed are found for Pc 3, 4, and 5 at both calgary and Leduc. The data, obtained in September and October 1970, confirm and extend similar results found in an earilier interval for Pc 3, 4, at Calgary alone, thus adding further evidence for a velocity-controlled contribution, such as the Kelvin-Helmholtz instability, to pulsation activity.