

Circular slide rule, cardboard (warped), for heat transfer calculations in pipes: designed by Dyna-Slide Co., Chicago, and assembled from Industrial and Engineering Chemistry, vol.54, no.1, pp.61-62 (1962)
Circular slide rule, cardboard (warped), for heat transfer calculations in pipes: designed by Dyna-Slide Co., Chicago, and assembled from Industrial and Engineering Chemistry, vol.54, no.1, pp.61-62 (1962)