296 INFECTIONS OF THE DIGESTIVE TRACT 



tains little or no indican. The cases in which large 

 quantities of indican are found in the urine must be 

 regarded as belonging in a different category from the 

 cases which are now under discussion. But it must be 

 admitted that a patient may show considerable ^changes 

 in regard to the indol production; a person who at one 

 time produces little intestinal indol will at other times 

 produce a considerable amount. Although the indican 

 of the urine is usually small or may be wholly absent, 

 the ethereal sulphates are often somewhat in excess. 

 The explanation of this fact is not clear. It indicates 

 that other putrefactive products than indol have been 

 absorbed from the intestine and have paired with sul- 

 phuric acid. In some cases perhaps phenolic bodies are 

 responsible for the increase in the ethereal sulphates, 

 but I have observed cases in which the increase in the 

 ethereal sulphates appeared to me to be out of propor- 

 tion to the amount of phenol recoverable from the urine. 

 It is quite possible that substances heretofore over- 

 looked have been largely responsible for the increase of 

 ethereal sulphates observed. There are, however, cases 

 of excessive saccharo-butyric putrefaction in which one 

 cannot say that the ethereal sulphates are in excess. 



Of the formation of sulphur compounds hi the intesti- 

 nal tract during the process of saccharo-butyric putre- 

 faction little is yet known. There is no evidence that 

 hydrogen sulphide is produced in excessive amount in 

 these cases. As regards the formation of mercaptan, 

 the evidence is against the view that anything more 

 than a trace of methyl mercaptan is liberated from the 



