appetite is not always a safe guide to follow.

_How can one know whether the strength or the quantity of the food
should be increased?_

In the early weeks it is well first to increase the strength of the
food, the next time to increase the quantity, then the strength again,
etc. After the fourth or fifth month, the quantity, chiefly, should be
increased.

_If a slight disturbance or discomfort occurs after the food has been
strengthened, is it best to go back to the weaker formula or to
persist with the new one?_

Symptoms of minor discomfort are seen for a day or two with many
infants after an ordinary increase in food; but in most cases an
infant soon becomes accustomed to the stronger food and is able to
digest it. If, however, the symptoms of disturbance are marked, one
should promptly go back to the weaker formula. The next increase
should be a smaller one.

_Should one be disturbed if for the first two or three weeks of
artificial feeding the gain in weight is very slight or even if there
is none?_

Not as a rule. If the infant does not lose weight, is perfectly
comfortable, sleeps most of the time, and does not suffer from any
symptoms of indigestion, such as colic, vomiting, etc., one may be
sure that all is going well and that the infant is becoming used to
his new food. As the child's appetite improves and his digestion is