INDIGO. 



367 



skilled labour than is believed to obtain anywhere in South America, 

 this inferiority in intrinsic value might be avoided. This done, the 

 crop would be a very profitable one, a moderate yield being about 

 50 lbs. of marketable indigo to the acre of ground devoted to the 

 cultivation of the plants. The crop seems adapted to a wide range of 

 country, the Hispaniola indigo growing in a deep, rich soil ; the 

 Bahamas variety in the poorest ground of So^ fch Carolina ; and 

 the wild or indigenous kind being stated to bf hardy and thrifty 

 under almost all conditions. In South Carolin* the seed has been 

 sown after the first spring rains, and the plants c Jt successively in the 

 early part of July and toward the end of August. The weeds must 

 be kept down with the greatest care. Formerly one labourer was 

 allowed to every two acres of ground, but it is believed that with 

 improved machinery twice this area can be cultivated per man 

 employed. The manufacture is described as follows : — 



" When the plant is beginning to blossom, it is fit for cutting. 

 When cut, great care should be taken to bring it to the steeper 

 without pressing or shaking it, as a great part of the beauty of the 

 indigo depends upon the fine farina which adheres to the leaves of 

 the plant. The apparatus for making the indigo is inconsiderable 

 and not expensive, for, besides a pump, the whole consists only of vats 

 and tubs of Cyprus wood. 



" The indigo, when cut, is first laid in a vat about 12 or 14 feet 

 long, and 4 feet deep, to the height o' about 14 inches, to macerate 

 and digest ; then this vessel, which is -ailed the steeper, is filled with 

 water; the whole having laid from'-,bout twelve to sixteen hours, 

 according to the weather, begins to ferment, swell, rise, and grow 

 sensibly warm. At this time spars of wood are run across to mark 

 the highest point of its ascent ; when it falls below this mark they 

 judge the fermentation has attained its due pitch, and begins to abate ; 

 this directs the manager to open a cock and let off the water into 

 another vat, which is called the heater. The gross matter that 

 remains in the first vat is carried off to manure the ground, for 

 which purpose it is excellent, and new cuttings are put in, as long 

 as the harvest of the weed continues. When the water, strongly 

 impregnated with the particles of indigo, has run into the second vat 

 or beater, they attend with a sort of bottomless buckets, with long 

 handles, to work and agitate it when it froths, ferments, and rises 

 above the rim of the vessel that contains it. To allay this violent 

 fermentation, oil is thrown in as the froth rises, which instantly sinks 

 it. When this beating has continued for twenty, thirty, or thirty-five 

 minutes, according to the state of the weather (for in cold weather it 

 requires the longest continued beating), a small muddy grain begins 

 to be formed ; the salts and other particles of the plant, united, dis- 

 solved, and before mixed with the water, are now reunited together 

 and begin to granulate. To discover these particles the better, and to 

 find when the liquor is sufficiently beaten, they take up some of it from 

 time to time on a plate or in a glass. When it appears in a hopeful 

 condition, they let loose some lime-water from an adjacent vessel, 

 gently stirring the whole, which wonderfully facilitates the operation, 

 the indigo granulates more fully, the liquor assumes a purplish colour, 



