Comparison of experiments 16 and 45 indicates that kz does not. vary significantly with ,u over the interval 0.4 to 0.8. Acknowledgments.-The author is indebted to the late Professor William C. Bray, of the University of Clalifornia, not only for suggesting this problem, but also for his encouragement and guidance during the preliminary work which ultimately led to the present investigation. Thanks are gratefully given to: Armando A. Rodrigues, Edgar Howard, Jr., and Wallace Hay for ...
