of loam. The soil should be able to
maintain very uniform conditions of moisture. Sudden variations in the
amount of water supplied are injurious: a sandy soil cannot retain
water; on the other hand a clay soil often maintains too great a supply,
and rank growth with excess of foliage ensues. The best soil for cotton
is thus a deep, well-drained loam, able to afford a uniform supply of
moisture during the growing period. Wind is another important factor, as
cotton does not do well in localities subject to very high winds; and in
exposed situations, otherwise favourable, wind belts have at times to be
provided.

_Cultivation in the United States._--The United States being the most
important cotton-producing country, the methods of cultivation practised
there are first described, notes on methods adopted in other countries
being added only when these differ considerably from American practice.

The culture of cotton must be a clean one. It is not necessarily deep
culture, and during the growing season the cultivation is preferably
very shallow. The result is a great destruction of the humus of the
soil, and great leaching and washing, especially in the light loams of
the hill country of the United States. The main object, therefore, of
the American cotton-planter is to prevent erosion. Wherever the planters
have failed to guard their fields by hillside ploughing and terracing,
these have been extensively denuded of soil, rendering them barren, and
devastating other fields lying at a lower level, which are covered by
the wash. The hillsides have gradually to be terraced with the plough,
upon almost an exact level. On the better farms this is done with a
spirit-level or compass from time to time and hillside ditches put in at
the proper places. In the moist bottom-lands along the rivers it is the
custom to throw the soil up in high beds with the plough, and then to
cultivate them deep. This is the more common method of drainage, but it
is expensive, as it has to be renewed every few years. More intelligent
planters drain their bottom-lands with underground or open drains. In
the case of small plantations the difficulties of adjusting a
right-of-way for outlet ditches have interfered seriously with this
plan. Many planters question the wisdom of deepbreaking and subsoiling.
There can be no question that a deep soil is better for the
cotton-plant; but the expense of obtaining it, the risk of injuring the
soil through leachin