The best manure for the sweet potato is anything green, such as fresh seaweed, green oats, bushes, or anything of the kind, put in in abundance.

Care should be taken to get early and good strong slips.  A slip with about six joints is quite long enough; three or four joints to be put under ground, and the rest above.  For slips, the land must be prepared as already described for the potatoes; this should be done before the slips are ready to cut.

The best way to plant slips is to drill, the same way as for the potatoes, only a little closer; then put the end of the slip in, leaving about two joints out of ground, placing them one foot apart.  The drills can be made in dry weather, so as not to have any delay when it rains; by this means a great many can be planted in a day.

The best land for sweet potatoes is the light sandy kind; a rich friable black mould, or a rocky substratum; for hill sides, rocky ravines, and places which would be called barren and unprofitable for other crops, are found to yield a good return when planted with sweet potatoes.  The best time to plant slips to get stock from, is the latter end of August or early in September, as the season may suit.

The sweet potato of Java, says Mr. Crawfurd, is the finest I ever met with.  Some are frequently of several pounds weight, and now and then have been found of the enormous weight of 50 lbs.  The sweetness is not disagreeable to the palate, though considerable, and they contain a large portion of farinaceous matter, being as mealy as the best of our own potatoes.  In Java it is cultivated in ordinary upland arable, or in the dry season as a green crop in succession to rice.

A tuberous root (Ocymum tuberosum), an inhabitant of the hot plains, is frequently cultivated in Java.  It is small, round, and much resembling in appearance the American potato, but has no great flavor.  Its local name is kantang.

CASSAVA OR MANIOC.

Of this plant, which is a shrub about six feet high, extensively grown for its farinaceous root, there are several species, nearly all natives of America, principally of Brazil, whence it derives one of its common names of Manihot or Mandioc.  Two species of Manihot have been found indigenous in South Australia.  The varieties commonly cultivated for their roots, are the sweet and the bitter.

1.  Sweet cassava (Janiphi (or Jatropha,) Loeflingii, Kunth; Manihot Aipi, of Pohl).—­This species has a spindle-shaped root brown externally, about six or seven ounces or more in weight, which contains amylaceous matter, without any bitterness, and is used as food, after being rasped and washed, so as to cleanse it from the fibrous matter, in the same manner as arrowroot is prepared.  It is distinguished from the bitter cassava by a tough ligneous fibre, which runs through the heart of the tuber.  Manihot starch is sometimes imported into Europe under the name of Brazilian arrowroot.  The cassava is known in Peru as yucca.