The indigo imported from the western hemisphere was for some time considered superior in quality to that of the East. Its cultivation, however, has been neglected, and the Bengal indigo is preferred at present to any imported from South America, where it is now only cultivated by the Brazilians and Colombians. If proper attention were paid to the cultivation of the plant, and to the preparation of the dye, it is very likely part of that important trade would be brought back. It thrives best in a moist climate, and the interior of Guiana, chiefly newly-cleared land, would be well adapted for it.
The late Mr. Dunlop ("Travels in Central America") gives an interesting description, which, at the risk of repetition in some points, I shall give entire.
"Several vessels generally arrive at the Union from South America at the time of the periodical fairs, where nearly all the indigo (the only produce of any importance), is disposed of; formerly it reached 10,000 bales, but at present it does not at most exceed 3,000 bales of 150 lbs. each.
The indigo well known in Europe by the name of Guatemala indigo, was never cultivated in that province (in the same manner as not a grain of the Honduras cochineal is grown there), being entirely grown in the state of San Salvador, in the vicinity of San Miguel, San Vicenti, and the City of Salvador, with the exception of a small quantity of very superior quality grown in the state of Nicaragua, and a few bales in Costa Rica, which is all consumed in the State. Under the government of Spain, the produce of the state of San Salvador alone had reached 10,000 bales, and that of Nicaragua 2,000; the produce of San Salvador in 1820, two years before its independence, being 8,323 bales. But since 1822 the annual produce had gradually declined, and in 1846 it did not exceed 1,000 to 1,200 bales, nearly all the indigo estates being abandoned, partly, no doubt, from the great fall in the price of the article, but more on account of the impossibility of getting laborers to work steadily.
The plant cultivated in Central America for the manufacture of indigo, is the triennial plant, supposed to be a native of America; but there is also an indigenous perennial plant, abounding in many parts of Central America, which produces indigo of a very superior quality, but gives less than half the weight which is produced by the cultivated species. The ground for sowing the indigo seed is prepared in April,—a piece of good forest land near one of the towns being selected, a part is cut to make a rude fence, and the remainder burnt, which is easily accomplished, as everything is very dry at that season; and the ground is afterwards scratched with two sticks, fastened crosswise, to resemble somewhat the shape of a plough, and the seed scattered over it by hand. The rainy season always commences early in May, and the indigo is ready for cutting about the middle of July, taking about two and a half months to come to perfection. The growing crop somewhat resembles lucerne, and is in the best state for making indigo, when it becomes covered with a sort of greenish farina.
The crop of the first year is small, and sometimes not worth manufacturing; that of the second year is the best, and the third is also very good, if it has been carefully weeded; but many indigo fields have lasted more than ten years without being re-sown, as the seed which falls naturally springs up again, and where the land is good yields nearly as large a crop as a new sown field. When the plant is ready for manufacturing, a number of men are collected, each of whom is either provided with, or brings his own mule or horse, if he has one. Two men always go together, cut the plant, then about the height of full-grown red clover, and take it to the vats, which are large tanks made of brick and lime, holding at least 1,000 gallons, and some as much as 10,000. Into these the plant is thrown till they are nearly full, when weights are put above it to prevent its floating; and the vats filled with water till it covers the mass of the indigo plant. After remaining from twelve to twenty-four hours, according to the state of the plant, weather, and other circumstances (the time required being determined by the color which the water assumes), the herb is taken out, and the water beaten with paddles in the very small vats, and by a wheel suspended above and turned by men or horses in the larger ones, till it changes from a green color, which it has acquired ere the removal of the herb, to a fine blue, when it is allowed to stand for some hours, till the coloring matter has settled to the bottom of the tank, a process which is generally hastened by throwing in an infusion of certain herbs to facilitate its settlement, or as the natives term it curdle (cuajar) the colored water. As soon as all the color has settled, the water is drawn off, and the blue, which is of the consistency of thick mud, is taken out of the vat and spread upon cotton, or coarse woollen cloth, and dried in the sun. The color in a great measure depends upon removing the herb exactly at the proper time, and upon properly beating the water, neither too long, or too short. Unless these processes are properly performed, the indigo will not be of first-rate quality; but some estates will never produce the best indigo, whatever care may be bestowed on the manufacture.
A mansana, of 100 yards square, which is nearly two British statute acres, produces generally about 100 to 120 lbs. of indigo, the carriage and cutting of the herb costing about twenty dollars, and the cleaning of the field and all other expenses connected with it, including the manufacture of the indigo, about as much more.
The indigo of Central America is not put into moulds when drying, as that of Bengal, but is allowed to remain in the rough shape in which it dries, and without further preparation is ready for baling and exportation.
The bales are generally made up in 150 lbs. each, and the quality is classed by numbers, from 1 to 9; Nos. 1 to 3 being of the quality called cobres in Europe; Nos. 4 to 6 of that called cortes, and Nos. 7 to 9 of that called flores; Nos. 1 to 6 do not at present pay the expenses of manufacture, and are never intentionally made. No doubt, with a little more skill in the manufacture, the whole might, as in Bengal, be made of the quality called flores; but such improvements cannot be expected till a new race of people inhabit Central America. At present about one-half of the indigo produced is under No. 7, and as the cultivation is said not to pay at the present prices—and, indeed, hardly can be supposed to compete with Bengal, a country where labor is so much cheaper, and capital abundant—it is probable, that the cultivation will shortly be entirely abandoned, unless the price should again rise in Europe." In 1846, 21,933 lbs. of indigo were exported from Angostura.
The following particulars were contributed to my "Colonial Magazine," by the late Dr. Edward Binns, of Jamaica:—