f the plowman's wearily making one furrow at a time, the
gang-plows of the plains cut many furrows at one time, and instead of
walking the plowman rides. The shredder and husker turns the hitherto
useless cornstalk into food, and at the same time husks, or shucks, the
corn.

The farmer of the future must know three things well: first, what
machines he can profitably use; second, how to manage these machines;
third, how to care for these machines.

[Illustration: FIG. 276. PROPERLY PROTECTED TOOLS AND MACHINES]

[Illustration: FIG. 277. UNPROTECTED TOOLS AND MACHINES]

[Illustration: FIG. 278. THE HARVESTER AT WORK]

[Illustration: FIG. 279. IN NEED OF IMPROVEMENT]

The machinery that makes farming so much more economical and that makes
the farmer's life so much easier and more comfortable is too complicated
to be put into the hands of bunglers who will soon destroy it, and it is
too costly to be left in the fields or under trees to rust and rot.

If it is not convenient for every farmer to have a separate tool-house,
he should at least set apart a room in his barn, or a shed for storing
his tools and machines. As soon as a plow, harrow, cultivator--indeed
any tool or machine--has finished its share of work for the season, it
should receive whatever attention it needs to prevent rusting, and
should be carefully housed.

Such care, which is neither costly nor burdensome, will add many years
to the life of a machine.

SECTION LXVI. LIMING THE LAND

Occasionally, when a cook puts too much vinegar in a salad, the dish
becomes so sour that it is unfit to eat. The vinegar which the cook uses
belongs to a large group of compounds known as acids. The acids are
common in nature. They have the power not only of making salads sour but
also of making land sour. Frequently land becomes so sour from acids
forming in it that it will not bear its usual crops. The acids must then
be removed or the land will become useless.

The land may be soured in several ways. Whenever a large amount of
vegetable matter decays in land, acids are formed, and at times sourness
of the soil results. Often soils sour because they are not well drained
or because, from lack of proper tillage, air cannot make its way into
the soil. Sometimes all these causes may combine to produce sourness.
Since most crops cannot thrive on very sour soil, the farmer must find
some method of making his land sweet again.

So far as we now know, liming the land