t and final lack of perfect distribution of the
former remain important. The stone is relatively easy to handle, being
slightly granular and passing through a distributor without trouble. The
fact that it is not caustic, like the hydrated, is in its favor. When
everything is taken into account, one is justified in using limestone or
air-slaked lime at a cost per ton three-fourths as great as that of lump
lime. It is to be borne in mind that in these estimates the cost per ton
is not that at the factory or at one's own railway station, but on the
farm. The freight and cartage to the farm are based on weight of
material, and more material per acre is required when the worthless
portion has not been driven off by burning. If one must use one and
three-quarters tons of limestone to have the equivalent of one ton of
fresh burned lime, it is evident that the cost of freight and cartage of
the worthless portion might make cost prohibitive if distances were very
great. Farms lying a long distance from a railway station may easily
find that fresh burned lime is the only form of lime they can afford.
The basis for correct estimate is cost delivered in the field.

_Storage._ One advantage possessed by the limestone is ease of storage.
There is no inconvenience or loss. The stone may be ordered at any time
of the year when teams are least busy upon other work, and it can be
held till wanted. In this way the cost of cartage to the farm may be
kept relatively low, and the material is at hand when wanted, regardless
of rush of work or delays of railroads. This advantage is partial
counterbalance to the cost of freight on the worthless portion of
unburned stone.

_Valuing Limestone._ The estimates, so far as labor and convenience are
concerned, are merely suggestive, and rest upon the presumption that the
stone is satisfactorily fine. It has been urged in another chapter that
immediate effectiveness is determined by fineness, but as a working
basis we assumed that when all the stone would pass through a screen
having sixty wires to the inch it would give the desired results. The
coarsest portion would not be available at once, but when an application
is heavy enough to serve for a year or more, we have enough very fine
material in such a grade of stone to meet immediate need. When
estimating values of such a grade and coarser grades, the amount per
acre to be used is a factor. The coarse is unsatisfactory if the price
is not low enoug