per cent of the energy value of the corn consumed by it, and in
pork-production this percentage scarcely rises to 16. This is the
reason meat-making animals give way before increase in population in
congested countries. Their office becomes, more and more, the
conversion of products inedible to man to edible products. In our
country their number will increase, doubtless, for a long period of
time, finding their places more surely on eastern farms rather than on
western ranches. They must find the cheaper land, and that is no longer
confined to the west. They must be where coarse materials, inedible to
man, are found, and that is on eastern as well as on western farms.
Their office will not be the conversion of crops into manure, but the
conversion of coarse materials into human food in the form of meat or
milk. This is the trend, and while the consummation may happily be far
in the future, its consideration helps us to an appreciation of the
facts regarding nature's provision for maintaining the productiveness
of the soil.

Sales off the Farm.--The day is now here when the major portion of
human food must be provided in grain and vegetables and fruit, and the
demand for hay and grain for animals off the farm is very large. Fiber
products likewise must be supplied. The draft upon the soil is heavy,
but it must be good farm practice to supply bread and vegetables and
fruit to the 70 per cent of our population that is not on farms. The
great majority of farmers do not feed all their crops to livestock, and
the amount of food-stuffs, for human beings and animals, that is now
going off the farms is none too great.

Many farmers who incline to believe that they are safely guarding
fertility by feeding the most of their crops are not returning to the
fields one third of the plant-food that their crops remove. There is no
virtue in feeding when the manure is permitted to waste away. The
losses in stable and barnyard, the wastes from bad distribution by
animals, and the sales from the farm of some crops, animals, and milk,
lead to the estimate that one half of the farms on which livestock is
kept do not give to the fields in the form of manure over 30 per cent
of the fertility taken out of them by crops. This estimate, for which
no accurate data is possible, probably is too high. The sales of food
for man and animal are a necessity, and the scheme of farming involving
such sales is right, provided the farmer makes use of other