29

and the proportion of contained cellulose scanty, digestion is very complete and
that under contrary conditions, low absorption is to be expected. Unfortunately
the dietaries of Bengal jails are very bulky and contain a large amount of cellulose
so that digestion and absorption is very imperfect: we have rarely found more
than 55 per cent. of the protein of the ordinary jail diet absorbed when the
full diet was consumed. This is in general agreement with the findings of other
observers as the following table, compiled by Hutchison, shows:—

    Relative absorption of the protein of various foods—

Diet.

  Protein not absorbed.
Meat             2.3 per cent.
Lentil flour             10.5
Dried peas             17.0
Beans             30.3
Potatoes             32.0
Lentils (soaked and boiled)             40.0

The fact that in Bengal jail diets the absorption of protein is on an even lower scale
than that given in the above list can be quite satisfactorily explained by the ex-
treme bulkiness of the prisoners' full diet when cooked; as evidence of this we find
that diminution in the bulk of the diet is at once accompanied by an increase in
the percentage of protein absorbed.

     One factor in the causation of this deficient absorption of protein, besides those
already referred to, is that the presence of a large amount of starch in the intestines
appears to be unfavourable to the absorption of protein.

     Hutchison attributes this to the fermentation of part of the starch leading to
the production of acids that unduly quicken the intestinal movements, and hurry
the contents through the small bowel where absorption is most active, into the
large bowel where absorption is at a minimum.

     That active fermentation does take place on jail dietaries there is plenty of
evidence to show, and there is no doubt that one reason, why a diminution in the
bulk of these diets is followed by an increased protein absorption, is that the exces-
sive fermentation is lessened, and the intestinal contents are not so hurried on,
more, relatively and actually, of the protein of the diminished diet being absorbed.
According to Hutchison the total capacity of an ordinary sized European stomach
is about 1,200 grammes and the weight of the ordinary cooked jail diet is at least
4,000 grammes, so that the stomach would be required to be filled to the extreme
limits of its capacity three times a day in order to get through the total amount.
Of course the habitual ingestion of these bulky diets leads to distension of the
stomach and bowels with a consequent disproportionate abdominal development.
This increase in the capacity of the stomach allows of more food being taken
and also, when the bulk of the food is decreased, gives rise to the feeling,