of the partially depleted surface removed by erosion year by year,
the supply of phosphorus is thus permanently provided for unless the
bed rock is brought too near the surface. It is doubtful if the
direct addition of phosphorus to your sloping lands will ever be
necessary or profitable. Certainly such addition is not advisable
until you have brought the land to as high a state of fertility as
is practicable by means of limestone, legumes, and manure."

"That seems clearly to be the case with most of the land now under
cultivation on this farm," said Mr. West "Can you tell me anything
about this hydrated lime?

"I can tell you it is correctly named," Percy replied. "_Hydrated_
means _watered,_ and an investment in hydrated lime is properly
classed with other watered investments. If you prefer to use
hydrated lime I would suggest that you buy fresh burned lump lime
and do the hydrating yourself, which only requires that you add
eighteen pounds of water to each fifty-six pounds of quick lime; in
other words, that you slack the lime by adding water in the proper
proportion. Both quick lime and hydrated lime are known as caustic
lime. Webster says that the word _caustic_ means 'capable of
destroying the texture of anything or eating away its substance by
chemical action.'

"This definition is correct for caustic lime, as you can easily
determine by keeping your hand in a bucket of slacked lime a few
minutes. Caustic lime eats away the organic matter of the soil. In
an experiment conducted by the Pennsylvania Experiment Station,
during a period of sixteen years, eight tons of hydrated lime
destroyed organic matter equivalent to thirty-seven tons of farm