INFECTIONS OF THE DIGESTIVE TRACT 145 



material to a beaker of distilled water. Under these 

 circumstances the color compound diffuses out into the 

 water and imparts to it a distinct and often strong red 

 color which is frequently more pronounced than one 

 would have predicted from the appearance of the mate- 

 rial which has developed the red color under the influ- 

 ence of the Schmidt procedure as ordinarily carried out. 



In the course of a systematic examination of the faeces 

 from normal individuals and from many pathological 

 series it was noted that the mercuric chloride reaction 

 was strongest in persons suffering from intestinal dis- 

 orders, especially in those with intestinal putrefaction. 

 The weakest reactions were found in the case of alcoholic 

 stools and in those of children and young adults present- 

 ing only slight indications of intestinal putrefactive 

 decomposition (low ethereal sulphates, absence of indican, 

 and low phenol). 



The Dimethylamidobenzaldehyde Reaction of the Fceces. 

 - If one extracts human faeces with an aqueous sodium 

 chloride solution (two grams of fseces to twenty grams 

 of 0.85 per cent, sodium chloride solution), the extract 

 will usually yield a color reaction with a suitably 

 prepared acid solution of Ehrlich's aldehyde. 1 In the 

 case of healthy children or adolescents on a mixed diet 

 the color obtained is usually a light rose, and may be very 

 faint. Between this light tint and a very deep cherry- 

 red, all transitions are met. 2 



1 Water, 270 c.c.; concentrated H 2 S0 4 , 30 c.c.; Ehrlich's alde- 

 hyde, 15 grams. 



2 We have employed a graded color scale in order to record our 

 results with some degree of accuracy. 



