74 CICATRIZATION OF WOUNDS 



area was precisely our unknown factor, it could not be 

 utilized. 



I realized, however, that if the area itself could not be used, 

 there existed an element which increased regularly as the area 

 diminished and that the surface was necessarily a function of 

 this element. It was what can be called the age of the wound, 

 namely the number of days gone by since the beginning of the 

 experiment, since the moment when the wound has become 

 bacteriologically sterile. This age could be known at all 

 times. Unfortunately it increased much more rapidly than 

 was necessary. I fell into the opposite extreme and obtained 

 decreasing values with my formula. However, by turning over 

 this problem from all angles I noticed that the discrepancies 

 increased as a reciprocal function of the square root of the 

 successive surfaces. The solution was at hand. The decrease 

 of the surface being a function of the time, it sufficed to intro- 

 duce in the denominator the square root of the age of the 

 wound, necessarily a reciprocal function of the square root of 

 the areas. 



By means of an artifice, I thus replaced the area by a factor 

 on which it depended quantitatively, and I corrected the 

 formula in function of its decreasing size, without taking 

 anything but the age into consideration. 



It must be admitted that I had been very lucky. The 

 correction was much simpler than I had thought. I never 

 imagined, when first checking the new formula, that it would 

 be unnecessary to introduce auxiliary constants, which are the 

 terror of physicists, for they are the proof that the mechanism 

 of the phenomenon is far from being solved. I thought I was 

 only nearing the solution when I wrote the equation 



^~^' =k (3) 



S{t-^\/T) 



T being the number of days since the beginning or the age 

 of the wound and k the coefficient which had to be stabilized, 

 I immediately deduced from formula (3) the value *S"' of the 

 surface at the time T' 



