Our knowledge of the conditions regulating the digestion and absorption of food-products within the intestinal canal would not be complete without some reference to the processes of decomposition emitting from the presence of bacteria in the intestinal tract. In the healthy breast-fed child fermentative processes predominate over those of putrefaction. In the healthy child who is artificially nourished, putrefactive processes to a limited extent are always demonstrable in the intestine; under diseased conditions the evacuations usually mani fest from their offensive odor the considerable degree of putrefaction Present (even when the infants are breast-fed). We must assume that the intestinal secretions furnish the material which undergoes these changes, for we know that milk is not liable to putrefaction, in fact milk-sugar may to a certain extent hinder putrefaetion. Leaving now the field of strictly proven facts we know that the amount of the intes tinal secretions is increased by artificial feeding and by certain diseased conditions, both of which promote putrefaction, all the more since the antiseptic action of the gastric juice is checked and limited under these conditions. In the healthy breast-fed child, fermentation exceeds putre faction at all times, since the intestinal secretions are less active and the antiseptic action of free hydrochloric acid reaehes its full develop ment. A eertain symptomatic importance must then be ascribed to
the seeondary process of intestinal putrefaetion in the infant's intestinal tract; whether the products of putrefaction can directly influence or injure the organism, is not yet definitely known.
The finding of products of intestinal putrefaction in the urine of the infants helps to substantiate what has just been said. Tialican is always absent from the urine of healthy breast-fed children, is not often found in the urine of artifieally fed infants, but is frequently present in acute and chronic disturbances of nutrition. What we know about the ethereal sulphates in the urine during the first year, eorroborates this view. The relation of the biliary coloring matter to intestinal putre faction may aid in diagnosis. Bilirubin is found in the feces where there is no putrefaction (healthy breast-fed child); when there bi putrefac tion its reduction to liydro-bilirubin (urobilin, stercobilin) is favored Schinidt's sublimate reaction— Schlkora). In older children on a mixed diet as in adult life, we find under normal conditions intestinal putrefaction, hydrobilirubin in the stools, and decomposition products in the urine.