The marked stimulatory effect of locally applied pepsin-digested bovine tracheal cartilage upon wound fibroplasia and collagen deposition has been well documented by Prudden and his group.1,2 Not only is its effect marked at the seventh postoperative day, but it has been shown3 that the phenomenon is demonstrable at a very early time in the course of wound healing and persists at approximately the same relative advantage (over the controls) until the 11th postoperative day (the last day in which measurements were made). This stimulation of the repair process did not change the basic relationship between wound tensile strength andthe time since wounding, this being the same in the control and experimental groups of the study.3 The function which expressed this relationship best had the same form as that which characterizes the curve of growth of the normal rat.3
It became apparent that it was of importance