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deal of valuable soil, that would otherwise be washed away every 
year, can be retained by terracing the hillsides and heavy slopes. 
Were it not for such terracing the grape vine would not grow in 
many parts of Europe today. It is not always possible to carry 
out these principles, but where stones and wood are available ni 
sufficient quantities a great deal can be accomplished to save the 
land from gradual impoverishment. Stone walls or fascines built 
at certain intervals across the slopes or hollows will tend to arrest 
the rapid flow of the water during a rain storm and cause the 
precipitation of much of the soil particles carried along by the 
water. 
WINDBREAKS. 
Soils of a sandy or dusty nature are often carried away by 
strong winds during a dry season. Jt is extremely difficult to pre- 
vent this but often the planting of suitable trees in rows at regu- 
lar intervals has been found very beneficial. 
Improving the mechanical and physical condition of soils. 
LIMING. 
Usually all soils contain sufficient lime to serve as plantfood for 
any number of crops, although the form in which the lime is 
present may not be suitable for certain plants. Lime is, however, 
frequently used to correct unfavorable mechanical, physical or 
chemical condition of soils. The reasons for the use of lime on 
soils are manifold and consequently it is important to know which 
form of lime to use in order to produce the best results under the 
prevailing circumstances. It depends entirely upon the soil to 
be treated, and the object of the treatment. It is easy enough 
for a chemist to say, "Your soil needs lime, you should apply, 
say, 1000 lbs. of burnt or slaked lime per acre and you will see 
a great improvement." Very often this improvement fails to 
materialize, and it is not seldom that reverse results are produced 
or the results will only show after several years. The fact of 
the matter is it is extremely difficult to determine, from a chemi- 
cal analysis alone, in what form the lime should be applied to a 
given soil ; many other circumstances have to be taken into con- 
sideration. There is usually no other course to pursue than a 
practical experiment in the field. 
The forms in which lime is usually applied are as follows : 
Quicklime, powdered, slaked or hydrated. 
Carbonate of Lime. 
Sulphate of Lime (gypsum or land plaster). 
Phosphate of Lime (as mono-, di-and-tricalcium phosphate). 
