In dealing with cases such as I shall describe, it is needful usually to give and to have digested a surplus of food, so that we are more concerned now to know the forms of food which thin or fatten, and the means which aid us to digest temporarily an excess.
As to quantity, it suffices to say that while by lessening food we may easily and surely make people lose weight, we cannot be sure to fatten by merely increasing the amount of food given; something more is wanted in the way of digestives or tonics to enable the patient to prepare and appropriate what is given, and but too often we fail miserably in all our means of giving capacity to assimilate food.

As I have said before, and wish to repeat, to gain in fat is, in the feeble, nearly always to gain in blood; and I hope to point out in these pages some of the means by which these ends can be attained.
_Note_ .-- The statements made on page 21 and the following paragraphs about obesity in England and with us are no longer exact, but have been allowed to stand in the text as recording facts true at the time of writing them, in 1877.

At the present a medical observer familiar with both countries must note several decided changes: more fat people, more people even enormously stout, are seen with us than formerly, and fewer of the "inordinately fat middle-aged people" in England than used to be encountered.

With us the over-fat are chiefly to be found among the women of the well-to-do classes of the cities, and from thirty years old onward.

They persecute the medical men to reduce their weight, and the vast number of advertisements of quack and proprietary remedies against obesity indicate how wide-spread the tendency must be.
Among women somewhat younger, as indeed among men, the American observer whose recollection takes him back twenty-five years must note a more hopeful change, a very decided average increase of stature, not merely in height but in general development.