s no
exception to this rule. Milk even very slightly acid is certain to
disagree with an infant; it is therefore always worth while the moment
that a hand-fed infant seems ailing to ascertain this point. If
alkaline, the milk will deepen the blue colour of litmus paper, which is
to be had of any chemist; if acid, it will discharge the colour and turn
it red. It is, perhaps, as well to add that, as the oxygen in the
atmosphere tends to redden litmus paper, it should not be left exposed
to the air, but should always be kept in a glass-stoppered bottle.

The milk of the cow is very liable to alteration from comparatively
slight causes, and particularly from changes in the animal's diet; while
even in the most favourable circumstances if the animal is shut up in a
city and stall-fed, all the solid constituents of its milk suffer a
remarkable diminution; while the secretion further has a great tendency
to become acid, or to undergo even more serious deterioration. Mere
acidity of the milk can be counteracted for the moment by the addition
of lime-water, or by stirring up with it a small quantity of prepared
chalk, which may be allowed to subside to the bottom of the vessel; or
if it should happen, though indeed that is rarely the case in these
circumstances, that the child is constipated, carbonate of magnesia may
be substituted for the chalk or lime-water. If these simple proceedings
are not sufficient to restore the infant's health, it will be wise to
seek at once for another source of milk supply, and to place the
suspected milk in the hands of the medical officer of health or of the
public analyst, in order that it may be submitted to a thorough chemical
and microscopical examination.

The difficulty sometimes found in obtaining an unvaryingly good milk
supply, as well as practical convenience in many respects, has led to
the extensive employment of various forms of condensed milk. They form
undoubtedly the best substitute for fresh cows' milk which we possess,
and are a great boon especially to the poor in large towns where the
milk supply is often scanty, not always fresh, and sometimes of bad
quality. I should certainly prefer condensed milk for an infant to milk
from cows living in close dirty stables, such as my experience thirty
years ago made me familiar with in some parts of London.

Still all the varieties of condensed milk are far inferior in quality
to good fresh milk. They contain less butter, less albumen,