FECES 239 



within the gauze is then examined. If beads appear in much less than 24 hours 

 an accelerated motility is indicated, whereas an interval of 48 hours or over 

 elapsing indicates retarded motility. If gastric function alone is to be studied 

 silk threads are attached to the beads and the latter are withdrawn and examined 

 before they have passed into the intestine. 



19. "Separation" of Feces. In order to become familiar with the method 

 ordinarily utilized in metabolism experiments to differentiate the feces which 

 correspond to the food ingested during any given interval, and at the same time 

 to secure data as to the length of time necessary for ingested substances to pass 

 through the alimentary tract proceed as follows : Just before one of the three 

 meals of the day ingest a gelatine capsule (No. oo) containing 0.2-0.3 of a gram 

 of carmine or charcoal. Make an inspection of all stools subsequently dropped 

 and note the time interval elapsing between the ingestion of the capsule and the 

 appearance of its contents in the feces. Under normal conditions this period is 

 ordinarily 24 hours. This test is thus an index of intestinal motility. 



20. Influence of Foods upon the Color of the Stool. Ingest a diet which 

 contains a liberal quantity of one of the following articles of diet, "separate" the 

 feces (page 587) and after the "marker" appears note the color of the stools 

 evacuated : 



Article of diet Color of stool 



Milk, 



Light yellow or grayish white. 



Meat i Brownish black. 



21. Quantitative Determination of Fecal Amylase (The Author's 1 Modification 

 of Wohlgemuth's 2 Method). Weigh accurately about 2 grams of fresh feces into 

 a mortar, 3 add 8 c.c. of a phosphate-chloride solution (o.i mol dihydrogen sodium 

 phosphate and 0.2 mol disodium hydrogen phosphate per liter of i per cent sodium 

 chloride), 2 c.c. at a time, rubbing the feces mixture to a homogeneous consistency 

 after each addition of the extraction medium. Permit the mixture to stand at 

 room temperature for a half-hour with frequent stirring. We now have a neutral 

 fecal suspension. Transfer this suspension to a 15 c.c. graduated centrifuge tube, 

 being sure to wash the mortar and pestle carefully with the phosphate-chloride 

 solution and add all washings to the suspension in the centrifuge tube. The sus- 

 pension is now made up to the 15 c.c. mark with the phosphate-chloride solution 



1 Hawk: Arch. Int. Med., 8, 552, 1911. 



2 Wohlgemuth: Berl. kiln. Woch., 47, 3, 92, 1910; also seepage 192, this book. 



3 Duplicate determinations should be made. 



