INDIGO. %$] 



SECTION IV. 



Indigo. 

 Indigofera tinctoria. Linn. 



The indigofera genus is extensive, embracing not less than fifty- 

 one known species, chiefly natives of India and of the Cape. The 

 most important of the whole is that now before us, the common in- 

 digo plant, specifically denominated by Linneus from its useful 

 dye, indigofera tinctoria. This plant is now chiefly cultivated in 

 North and South Carolina, and the neighbouring state of Georgia ; 

 the dye obtained from it bears the name of the plant which pro- 

 duces it ; which was probably so called from India, where it was first 

 cultivated, and from which country, for a considerable time, the 

 whole of what was consumed in Europe was brought. This plant, 

 when grown, resembles the fern, and when young is scarcely dis- 

 tinguishable from lucern grass. Indigo is generally planted after 

 the first rains which succeed the vernal equinox : the seed is put 

 into the ground in small straight trenches, about eighteen or twenty 

 inches asunder, and is fit for cutting the beginning of July. It 

 cuts again toward the end of August, and if a mild autumn suc- 

 ceeds, there is a third cutting at Michaelmas. The indigo land 

 must be weeded every day, and the plants cleansed from worms. 

 Each acre yields sixty or seventy pounds weight of indigo, which 

 at a medium is worth fifty pounds. 



The indigo when cut is first laid in a vat about twelve or four- 

 teen feet long, and four deep, to the height of about fourteen 

 inches, to macerate and digest. Then this vessel, which is called 

 the steeper, is filled with water : the whole having lain about 

 twelve or sixteen houTS, according to the weather, begins to fer- 

 ment, swell, rise, and grow insensibly warm ; at this time spars of 

 wood are run across to prevent its rising too much, and a pin is 

 then set to mark the highest point of its ascent : when it falls be- 

 low this mark, they judge that the fermentation has attained its 

 due pitch, and begins to abate ; upon which the manager turns a 

 cock, and lets off the water into another vat, which is called the 

 beater ; and the gross matter that remains in the first vat is carried 

 off to manure the ground. 



When the water, strongly impregnated with the particles of in. 



