Masses of unchewed meat, gristle, tendon ends, fragments of bones etc., act analogously to the first group of vegetable masses considered.

In short, the only kind of indigestible residue which can be relied upon to produce a laxative effect, without more or less danger, is the soft, moss-like network of cellulose found in green vegetables, fresh or dried fruits, bulbs, tubers, soft roots and stalks etc. Even figs are objectionable on account of the small seeds.

It is much better to administer a medicinal cathartic than to employ dietetic measures that produce marked gaseous fermentation, that result in a large mass of residue containing undigested starch or that eventuate in a colliquative diarrhoea as practically always follows the excessive use of relatively innutritious vegetables.

Any kind of oil or fat when used in excess of the physiologic limit - about 150 grams a day - is laxative, even if no excess of fermentation occurs. Clear fat or oil, taken without other food, is more laxative than that properly mixed.

It is usually overlooked - indeed the observation may be claimed to be original, at least in its practical application - that normal movements of the bowels depend to some degree upon the production of carbon dioxid gas by the reaction of gastric hydrochloric acid with pancreatic, biliary and intestinal alkaline carbonates. It is a conservative estimate that, in the digestion of the three meals, at least one gram of pure hydrochloric acid is secreted by the stomach and more than enough alkali for its neutralization. From the molecular weights, it is a matter of simple calculation that each gram of hydrochloric acid yields 44/73 of a gram of carbon dioxid, occupying at body temperature and ordinary atmospheric pressure a volume of 1200 c.c. Thus, the maintenance of a digestive equilibrium between the acid and alkaline factors, is important in securing normal intestinal movements.

Any food may be considered constipating which contains tannic acid or which yields little indigestible residue. Thus, even liquid foods such as milk, provdiing that the quantity of water is not too great, that digestion is good and germ activity not excessive, and that balancing cathartic factors, including idisyn-cratic irritation are not present, are constipating. Tea is especially liable to produce constipation, not only because it contains considerable tannin to act upon the bowel, but because it is commonly used by those who take too little water and too little food, and also because it tends to depress gastric secretion so that the normal formation of carbon dioxid from the interaction of hydrochloric acid and alkaline carbonates, is diminished. Obviously, any great formation of organic acids by fermentation would result in carbon dioxid production and even irritative diarrhoea might result.

Milk curds which do not digest, may act to produce diarrhoea almost exactly like lumps of unchewed meat.

Very fine wheat or rice biscuits, especially if made with considerable raw flour may result in faecal accumulation.

Bread stuffs made of fine cereal flours, cooked milk, eggs, beef juice, etc., barring indigestion and fermentation, yield little residue, and are, therefore, constipating.

On an average diet, fully half of the faecal mass consists of bacteria, shed epithelium and true excrementitious matter, largely discharged in the bile. Thus, even on a diet as free as possible from indigestible residue, the faeces amount to 30 - 50 grams a day.

Intestinal Indigestion. Owing to the fact that intestinal digestion takes place in a long cavity, whose contents are not retained in any one place for a fairly regular physiologic period of considerable length, it is impossible, even by physiologic experiment, to make as definite statements regarding its course, as for that of gastric digestion. Owing, also, to the practical impossibility of withdrawing contents for examination from above, and to the fact that the faecal discharge always consists of overlapping ingredients, that digestion and absorption are normally nearly completed in the caecum, some hours before the faeces are finally obtainable and that digestive processes are confused by high grades of chemic change due to bacteria, it is impossible to study clinically, the process or results of intestinal digestion, with any degree of accuracy comparable to that of gastric digestion.

Hence, while it is very easy to use the term intestinal indigestion, it is very difficult to do so in an intelligent manner. That is to say, we cannot discriminate sharply between apparently functional and plainly organic disturbances of the intestine, nor can we discriminate indigestion from saprophytosis even to the approximate degree possible for stomach contents. Again, it must be remembered that true failure of digestion in the intestine is not so much a disturbance of the intestine as of the pancreas.

Thus, the intelligent dietetic treatment of so-called intestinal indigestion, must depend upon an examination of the faeces, a consideration of the perfection of mouth and gastric digestion, the indirect evidences of pancreatic and hepatic lesions, and the inspection of the rectum, if blood, mucus, pus etc. appear.

The intestine cannot be expected to digest dense masses of either vegetable or animal tissue. Hence, the appearance of undigested huckleberries, corn, peas, beans, tendon ends, pork rind etc., does not constitute a true intestinal indigestion but demands proper comminution, outside the body, or by mastication, or more careful trimming of food. Small macroscopic or microscopic masses of cellulose, plant hairs, and the yellow masses of altered muscle, are to be expected in any case. An excessive indigestion of relatively indigestible and innutritious vegetables naturally leads to increased peristalsis, watery discharges and considerable fermentation of cellulose. While literally an intestinal indigestion, such an occurrence, with relatively enormous waste of ingested nutriment is inevitable and the only appropriate radical treatment is to remove the dietetic cause.

In other cases, the so-called intestinal indigestion consists in a marked increase of saprophytosis, sometimes mainly involving the proteins by the increase in colon bacilli, in numbers or virulence, when indicanuria and sulphur-containing gases enable a clinical diagnosis to be made; sometimes mainly the carbohydrates, including cellulose. In some cases the bacillus lactis aerogenes is the principal offender. Again the saprophytosis consists in an enormous development of yeast cells, so that the faecal mass, if kept warm, rises almost like a mass of dough or froths if more liquid. Herter has demonstrated the frequent oc-curance of the bacillus aerogenes capsulatus.

In such cases, there is a general indication to purge the intestine, to administer small quantities of almost perfectly digestible foods, with artificial digestion or digestants, if necessary. In order to lessen the development of a particular kind of microor-ganism,|the pabulum should be changed, that is to say, an entirely different kind of diet should be instituted for a longer or shorter period. If the condition has been mainly one of putrefaction, meats should be discontinued and cereals and fresh vegetables should be given. Especially in infants and fever patients, there is often an indication to discontinue milk and use white of egg and meat extracts, with cereals if not contraindicated.

Many cases of so-called chronic intestinal indigestion are really cases of colitis, with mucus varying in consistency from a gelatinous mass to dense shreds, usually believed to be "casts," especially if tubular. The inflammation of the large intestine may be quite local, as a proctitis, typhlitis or appendicitis.

True intestinal indigestion can be determined-only by careful chemic tests either of the faeces directly or by means of Einhorn's method of attaching different kinds of food as mutton fat, tendon or catgut, muscle, raw and cooked potato, to beads of different colors, using gauze if necessary to prevent accidental detachment of friable substances.

For obvious physiologic reasons, a true intestinal indigestion usually indicates pancreatic failure. Much confusion has arisen from the search of medical Ponce de Leons after pathognomonic signs. It should be realized that an organic lesion of the pancreas, especially if localized, does not necessarily interfere to a conspicuous or even to an appreciable degree with function, and that repair and compensatory hypertrophy or superfunction may occur, just as for any other organ. It is precisely as irrational to expect macroscopic evidence of fat indigestion or absolute failure to digest raw starch in a pancreatic lesion, as to expect the average case of hepatic sclerosis to manifest glycosuria or the average case of pneumonia or pulmonary tuberculosis to manifest dyspnoea, of extreme degree. On the other hand, a functional failure may occur when the pancreas is not organically diseased.

Thus the dietetic management must correspond to the actual findings and not to what might be expected a priori.