A Study of Shower Curves with the Multiplate Cloud Chamber

With the multiplate cloud-chamber, cosmic-ray cascade showers up to 800 Mev were examined with respect to the shower curves and fluctuation. The form of the shower curve is in good agreement with the Wilson's Monte Carlo curve. And the fluctuation in the number of shower particles seems to be of the Poisson type. From the Shapiro's experiment and the authors', Wilson's results seem to be most reliable in both the absolute value and the form of the shower curve at least up to 800 Mev.