342 THE CHEMISTRY OF PROLIFERATION 



of the gauze, in spite of the fact that ulcers have been 

 treated with gauze all over, but only a part of them 

 with globin added, and the proliferation occurred to 

 the marked extent only where the globin was. We 

 therefore discarded gauze or dressings altogether, and 

 repeated the experiments. In a case where there were 

 several ulcers on one leg the surfaces of them all were 

 scarified, and small pieces of dried globin were "dotted" 

 all over one ulcer. The cell-proliferation occurred to a 

 marked extent in that ulcer, but only to a much less 

 extent in the others which were not so treated. 



Globin thus applied to a healing surface causes a 

 scab to form very rapidly (figs. Ill, 112), and the 

 cell-proliferation goes on beneath it. This scab forms 

 in an hour or two, whereas, if no globin is applied, it 

 takes several days for a scab to form on an ulcer 

 which has no dressing on it. Globin also causes ex- 

 tensive proliferation of the epithelium from the sides 

 of the ulcer. 



Unfortunately suppuration occurs under the scab, 

 no matter how "clean" the ulcer may be when the 

 globin is applied. The onset of suppuration, how- 

 ever, has been delayed by preparing the globin with 

 aseptic precautions throughout, thus: A solution of 

 haemoglobin is decomposed by boiling, and filtered, and 

 the globin solution is concentrated until it precipitates 

 by further boiling. It is evaporated to dryness at a 

 temperature of 60 C. and immediately sealed into sterile 

 glass tubes. Even with these precautions, suppuration 

 usually occurs under the scab in the course of a few 

 days. The scab is then removed with fomentations, 



