was finely
divided and distributed throughout the surface soil.

The Fineness of Limestone.--Experiments at the Pennsylvania experiment
station have shown that limestone has practically immediate
availability in an acid soil if all of it has ability to pass through a
screen having 60 meshes to the linear inch. Much of the limestone
meeting this test doubtless is fine enough to pass through an 100-mesh
screen. The requirement that a 60-mesh screen be used in testing is a
satisfactory one to the buyer that wants immediate results in the
field. A coarser product must be used in larger amount per acre, as
only the fine particles are available at once, and the object of the
application is to correct all the acidity. Where a coarse product,
containing some fine particles, can be used at such a low price per ton
that the application may consist of a large number of tons per acre,
the practice may be commended, but the essential thing is immediate
results, and only finely divided limestone can give them. Any long
railway or wagon haul makes a heavy application of coarsely pulverized
limestone inexpedient.

Hydrated Lime.--Many salesmen are too enthusiastic in their claims for
hydrated lime. It has advantages over pulverized limestone, stone-lime,
and pulverized lime, and there are disadvantages. The buyer of
pulverized limestone pays for the haul on 100 pounds of material to get
the 56 pounds of lime carried, while 74 pounds of the hydrate furnish
the same amount of actual lime, if all of it is a hydrate. While the
hydrate contains less strength than the stone-lime, it is in good
physical condition for distribution, and the stone-lime must be slaked.
The buyer will bear in mind, moreover, that much of the stone-lime
which is burned on farms comes from limestone that is not very pure,
and all impurity is waste. Most manufacturers of the hydrate locate
their costly plants where the limestone is relatively pure. Prudent
business reasons dictate such a course. A careful manufacturer of
hydrated lime takes out imperfectly burned and other faulty material
with screens. These advantages have some weight, but the fact remains
that a ton of pure stone-lime has considerably more acid-correcting
power than a ton of the hydrate.

Stone-lime.--Stone or lump-lime is composed of the 56 per cent of a
pure limestone that gives value to the limestone. Forty-four pounds of
waste material were driven off in the burning. Where railway or wagon