the course of the day, you would have
given one spoonful of gelatine, which spoonful has no nutritive power
whatever.

And, nevertheless, gelatine contains a large quantity of nitrogen, which
is one of the most powerful elements in nutrition; on the other hand,
beef tea may be chosen as an illustration of great nutrient power in
sickness, co-existing with a very small amount of solid nitrogenous
matter.

[Sidenote: Beef tea]

Dr. Christison says that "every one will be struck with the readiness
with which" certain classes of "patients will often take diluted meat
juice or beef tea repeatedly, when they refuse all other kinds of food."
This is particularly remarkable in "cases of gastric fever, in which,"
he says, "little or nothing else besides beef tea or diluted meat juice"
has been taken for weeks or even months, "and yet a pint of beef tea
contains scarcely 1/4 oz. of anything but water,"--the result is so
striking that he asks what is its mode of action? "Not simply nutrient--
1/4 oz. of the most nutritive material cannot nearly replace the daily
wear and tear of the tissues in any circumstances. Possibly," he says,
"it belongs to a new denomination of remedies."

It has been observed that a small quantity of beef tea added to other
articles of nutrition augments their power out of all proportion to the
additional amount of solid matter.

The reason why jelly should be innutritious and beef tea nutritious to
the sick, is a secret yet undiscovered, but it clearly shows that
careful observation of the sick is the only clue to the best dietary.

[Sidenote: Observation, not chemistry, must decide sick diet.]

Chemistry has as yet afforded little insight into the dieting of sick.
All that chemistry can tell us is the amount of "carboniferous" or
"nitrogenous" elements discoverable in different dietetic articles. It
has given us lists of dietetic substances, arranged in the order of
their richness in one or other of these principles; but that is all. In
the great majority of cases, the stomach of the patient is guided by
other principles of selection than merely the amount of carbon or
nitrogen in the diet. No doubt, in this as in other things, nature has
very definite rules for her guidance, but these rules can only be
ascertained by the most careful observation at the bedside. She there
teaches us that living chemistry, the chemistry of reparation, is
something different from the chemistry of the laboratory