r stimulating properties belonging to flesh, yet
the inhabitants of fishing-towns are shown to be unusually strong and
healthy. The flesh of some fish is white, and of others red; the red
holding much more oil, and being therefore less digestible. In _Salmon_,
the most nutritious of all fishes, there are, in a hundred parts, sixteen
of nitrogen, six of fat, nearly two of saline matter, and seventy-seven of
water. _Eels_ contain thirteen parts of fat. _Codfish_, the best-known of
all the white fish, vary greatly, according to the time of year in which
they are taken, being much more digestible in season than out (i.e., from
October to May). _Mackerel_ and _Herring_ both abound in oil, the latter
especially, giving not only relish to the Irishman's potato, but the
carbon he needs as heat-food. _Shell-fish_ are far less digestible, the
_Oyster_ being the only exception. The nitrogenous matter in oysters is
fourteen parts, of fatty matter one and a half, of saline matter two, and
of water eighty. At the time of spawning--from May to September--they lose
their good condition, and become unwholesome. _Lobsters_ rank next in
importance, and are more delicate and finer-flavored than _Crabs_. Both
are, however, very difficult of digestion, and should only be used
occasionally. The many forms of pickled and smoked fish are convenient,
but always less wholesome than fresh.

MILK comes next, and has already been considered in a previous chapter. It
is sometimes found to disagree with the stomach, but usually because
looked upon as drink and not as real food, the usual supply of which is
taken, forgetful of the fact that a glass or two of milk contains as much
nourishment as two-thirds of the average meal. The nitrogenous matter in
milk is known as caseine, and it is this which principally forms cheese.

CHEESE is commonly considered only a relish, but is in reality one of the
most condensed forms of nitrogenous food; and a growing knowledge of its
value has at last induced the Army Department to add it to the army ration
list. Mattieu Williams, after giving the chemical formulas of caseine and
the other elements of cheese, writes; "I have good and sufficient reasons
for thus specifying the properties of this constituent of food. I regard
it as the most important of all that I have to describe in connection with
my subject,--The Science of Cookery. It contains, as I shall presently
show, more nutritious material than any other food t