28 THE ACTION OF THE LIVING CELL 



the sponge may be utilized for the extraction of mucus, 

 bacteria, etc., from such foci. After the sponge has 

 been utilized for the desired purpose, it is resheathed, 

 and the instrument withdrawn from the stomach. 



The course of action of reagents applied in this 

 manner may be followed cytologically by the micro- 

 scopic examination of samples of the stomach mucosa 

 removed by means of intragastric nippers designed 

 for this purpose. In some instances the course of ac- 

 tion of gastric irritants was observed by means of a 

 permanent fistula established by making a valvular 

 opening in the anterior wall of the stomach. This 

 was accomplished by folding the mucous membrane 

 in such a fashion as to make a valve similar to the 

 ileocecal. (Turck, 1896a, 1898.) Upon introducing 

 a speculum and a small electric lamp through such a 

 fistula, the entire interior of the stomach could be 

 viewed; at other times, the valvular fold prevented 

 the escape of the stomach contents. 



Let us now consider the results obtained by the 

 application of such experimental methods. By means 

 of a needle douche introduced through the esophagus, 

 a 0.2% emulsion of mustard in water was douched over 

 the stomach mucosa of dogs in which gastric fistulae 

 had been established. The changes so induced were 

 observed through the fistula as described above. 

 Within five minutes a local hyperemia of the mucous 

 membrane was observed ; and after twenty minutes 

 the tissues were markedly congested. A similar local- 

 ized hyperemia of the mucosa was induced by the 

 introduction of water at a temperature of 40° to 45° C.,- 

 and by the mechanical stimulation of the membranes 



