FORMATION OF F^CES. 83 



Schmidt shows that the intermediate circulation of water toward the 

 intestine is far more considerable than its final excretion, and Water furnish- 

 amounts in one day to nearly one fourth of the whole quan- |^ 1] 

 tity of water in the body. 



As the digested mass passes onward, driven by the peristaltic motions 

 through the convolutions of the intestine, it becomes of a Complex chan- 

 more solid consistency, as the absorbents gradually remove testinai^on^" 

 its liquid portions. By the time it has reached the coacum, tents, 

 the same effect which arose in the stomach from salivary digestion is 

 repeated, for the traces of unabsorbed lactic acid cause nutritive diges- 

 tion to be again feebly resumed, at all events in herbivorous animals, if 

 not in man, whose ccecum is rudimentary, under the form of the appen- 

 dix vermiformis. From Peyer's glands a secretion has exuded, which 

 perhaps gives to the mass the characteristic odor it is now assuming, if, 

 indeed, these organs are not connected with absorption. The effete re- 

 mains are finally voided as fasces, which, due allowance being made for 

 the water they contain, amounting to about 75 per cent., may be rep- 

 resented as averaging about 1J ounce per day. These excrementitious 

 remains, colored yellow by the coloring material of the bile, are partly de- 

 rived from the residues of the food which have been unacted upon, and 

 partly from the decay of the system itself. The microscopt shows the 

 remains of cell membranes, and the walls of vegetable vas- Formation 

 cular tissues, starch granules, and chlorophyll, the relics of car- of faeces ' 

 tilaginous and fibrous tissues, shreds of muscular fibre, fat-cells. From 

 the digestive tract there have been derived mucus corpuscles, epithelial 

 cells, and the coloring matter of the bile. Perhaps, too, much of the wa- 

 ter which gives consistency to the fasces has been derived from the intes- 

 tinal walls, for in quantity, under certain circumstances, it may exceed 

 the amount that has been used as drink. 



In its passage through the intestine, that portion of the bile which has 

 not been absorbed undergoes- considerable changes, its conju- Disappearance 

 gated acids degenerating into dyslysin, which may be recog- of the blle - 

 nized in the fseces, as is also the case with the modified pigmentary mat- 

 ters ; the soluble mineral constituents are, for the most part, absorbed. 



The reducing agencies in the intestine, and the manner in which sub- 

 stances can find their way into the urinary secretion, is well Incidental re- 

 illustrated by the administration of indigo, which undergoes fnSntts? 11 

 deoxidation into the condition of suboxide of isatine, and will, tine, 

 notwithstanding the agency of arterial blood, appear in that condition in 

 the urine, to which, upon contact of the air, it imparts a blue tint, becom- 

 ing more intense under a prolonged exposure, and eventually indigo-blue 

 being deposited. Such a result not only shows how energetic are the re- 

 ducing agencies in the intestine, but also with what facility very oxidiz- 



