In case of forced convection, the coefficient of surface heat transmission is different from the former case of the natural heat convection and depends increasingly on the stream velocity and peripheral velocity of the cylinder, but not on the temperature difference. The experiments are performed as same as the case of the natural heat convection which was already reported in the previous paper, and these results are shown graphically in figures 1∼5. From these figures we found that the experimental formula [numerical formula] is sound.