In proportion as the caloric increases, azote is disengaged, the herbaceous mucilage separates, the vegetable is, decomposed, the mixture absorbs oxygen. At first the liquor takes in the basin a green tinge. It is strongly agitated, that the elements of the vegetable may subtilize, and the fermentation speedily augments to the highest degree. The fermenting fluid passes from a green to a violet tinge, and this by degrees changes to a blue colour.

The first fermentation takes place in the trempoire, in which very clear water had been previously placed. The plant is prevented from swimming, by being pressed beneath the surface. The state of the plant, the ground that produced it, and the season in which it was cut, are guides to direct the manufacturer. This fermentation takes place more or less promptly, according to causes which concur to hasten or retard it. Ten, twenty, and thirty hours are most frequently the term: it rarely requires a longer time. In Terra Firma, when not prevented by the state of the plant, nature of the soil, or the season, twelve hours suffice for the fermentation. The great art of the fabrication is to check it at a proper degree. If the fermentation is too feeble or too brief, the 'plant remains impregnated with much essential salt, which diminishes the quantity of the indigo. If it be too long, the tender extremities of the plant undergo a putrefaction which destroys the colour.

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The odour of the fermenting liquid, and the numerous flies which fly over it, are signs to which the indigo-makers of Terra Firma attach most weight. There was published at St. Domingo, some years ago, the following criterion to ascertain invariably the correct fermentation of the indigo. "It is only requisite to write on white paper with the matter to -be examined. If this ink be of very high colour, it is a proof that the fermentation is not yet at its true point. The experiment is repeated every quarter of an hour, till it is perceived that the liquid has lost its colour." This was pronounced an infallible index to shew the true point of fermentation. This test had its time and its mode; but the planters returned to the use of the silver cup.

When the fermentation is advanced, some of the liquid is thrown into a silver cup, and shaken till grains are formed: by their quality, and that of the fluid, they judge of the fer mentation. In this experiment, the best method is to draw off the liquid, by means of a spout or cock, from the cuve into the eup*

The active genius and constant observation of the inhabitants of St. Domingo have carried the preparation of colonial produce to a degree of perfection which the neighbouring colonies have been unable to attain. The fabrication of indigo alone seemed condemned to be the perpetual sport of chance, and the caprice of circumstances. Its success was always doubtful. The fabricator of indigo who only lost a tenth of the cuves, or yats, of that plant, was considered as skilful. There were some who lost s fourth, The honour of ascertaining invariable rules was reserved for the intelligence and experience of M. Nazou, an inhabitant of the quarter of Mirbalais. The arts are indebted to him for certain marks, according to which indigo is made upon principles as constant as those which direct the refiner in the manufacture of sugar. M. Bruley, who has imparted this discovery in an excellent Memoir upon Indigo, read in the Lyceum of Arts, on the 30th Floreal, year 9, expresses himself thus: These precious advantages France will benceforth enjoy. She owes it to the labours and the intelligence of Citizen Nazon, a colonist, and a proprietor at St. Domingo, but at present in France, and an associate of the Lyceum. By judicious observations and long experience he has been enabled to secure the success of all the cuves of indigo.

***To obtain this' colouring substance, the indigo plant must be cut in its maturity. It must be put entire to macerate in a basin of mason-work, called a cuve. The dimensions of it are twelve feet, French measure— quatre metres. The maceration requires from fifteen to thirty, and even thirty-six hours; more or less, according to the temperature that is experienced at the moment. It is also necessary to have regard to the quality of the plant, the nature of the soil that produced it, and that of the water in which it is immersed. The first index which shews that the maceration approaches its proper point, is the sinking of the scum, or foam, which rises into the space of about a sixteenth of a metre, that was left vacant in the cuve on compressing the herbs. (A metre is three feet). When the cuve is covered with a kind of crust of a copper blue, the moment of sufficient maceration is not far distant. This symptom, however, is Sinsufficient, and often deceitful. There is another, on which more reliance can be placed; that is, to draw from a spout, or cock, in the lower part of the cuve, a little of the fluid it contains. It is received in a silver cup: when the feculent particles begin to precipitate to the bottom of the cup,

After signs of complete, fermentation are obtained, the whole contents of the cuve are passed into the batterie, where they undergo another process still more important, as it is in tended to separate the carbonic acid, and to facilitate the reunion of the particles composing the blue feculæ or sediment. This object is obtained by violently agitating the fluid. No less

then it is judged that the herbs have attained the true degree of maceration for obtaining indigo. Such was the procedure most in use; but it too often led to error. A certain mean to secure correctness, is to observe carefully the water contained in the cup. Five or six minutes after it has been placed there, it forms round the sides of the cup a glory (aureole) or cordon of feculæ or sediment, at first of a green colour, and then blue. When the maceration is not at the requisite point, this cordon or girdle has difficulty to detach itself from the sides of the cup, but finally precipitates, and con centrates at the bottom of the vase, always towards the centre, and the water above it becomes limpid, though of a yellowish tinge.

"When these signs are perceived, they indicate infallibly the success of this first operation. The liquid is then passed into a second basin or cuve, made below the former. This second cuve is called batterie, because its use is to beat the fluid still charged with the fecule. That it may speedily detach itself, it is stirred: this operation is performed with the arm, or with a mill. It is essential that it be not beaten too long a time; excess of beating mixes anew the fecula with the water, from which they cannot be again separated, and the contents of the cuve are lost: in place of indigo, only troubled water is obtained.

*The latter inconvenience may be easily avoided with a little attention. When it is observed that the feculent particles are sufficiently united, the water is poured from the batterie into a third and smaller basin or cuve, called diablotin. The bottom of the batterie is found covered with a blue and very liquid paste: this is received in sacks of coarse linen, in form of reversed cones, and the watery parts are left to drain from them. The -sacks are then emptied upon tables in the sechoirs, or drying places; the blue paste is kneaded; 'when it becomes thick, it is spread, and cut in small (squares, that it may the sooner become dry. The indigo is then made, and is soon sufficiently dry to be marketable.-I. suppress details contained in a much longer memoir, of which I furnish only an extract. It was important to make known, that there exists a certain process, by pursuing which there is no fear of being deceived in the fabrication of indigo.

"Experience has proved that this process has never failed to produce complete success; more than fifteen hundred cuves, fabricated according to it in different quarters of St. Domingo, have furnished proofs of its correctness."

care, attention, and experience, are requisite in this, than the preceding operation. According as it is well or ill performed, it may correct the errors of imperfect fermentation, or may occasion the loss of indigo which has thus far been correctly fabricated. If it be not sufficiently beaten, the grain is left diffused in the water, without re-uniting at the bottom of the cuve; the mass of feculent matter that forms the indigo is also diminished. If it be beaten too much, the grain is dissolved and broken.

The facility with which the grain precipitates to the bottom of the batterie, is an unequivocal sign that the beating has arrived at the correct point. We should not hesitate to pour off the water, and to empty the miry or feculent matter into the third cuve, or Riposoir.

It only remains to put the indigo in sacks, which should be suspended to facilitate the expression of the water it still retains. It is then put to dry in the sun, in boxes made for the purpose. Before it is perfectly dry, it is cut in small pieces of an inch square, which detach themselves readily from the box when the indigo is entirely dry. The inbabitants of Terra Firma dry the indigo under sheds. This method is more tedious, but is favourable to the quality of the indigo. Its combination is more intimate, as is proved by the hardness it acquires. The different actions it experiences increase its lustre. In short, thes weight in proportion to bulk is greater than that of indigo dried in the sun. Yet, however well dried and drained the indigo may be, it always experiences in the first months of its fabrication a diminution sufficiently evident to warrant a hastening of the sale..

It is customary to pack the indigo in barrels, and thus.to circulate it in commerce. The Spaniards alone put it into packages of a hundred pounds, and so well conditioned, that the rough usage they encounter between the place of mangfacture and the sea-port does not occasion any damage.

Indigo is packed in sacks of coarse linen, and the sack vis covered with a beef's hide, so hermetically sewed, that nothing ycan - penetrate it. These packets are called seroons; they possess great advantages over barrels; they are more, solid;

may fall on stones without incurring danger; and are much more convenient for transportation. Two seroons make the load of one animal. They are stowed to much greater advantage in stores and buildings; and in their circulation in Europe, they have much less to fear from the carelessness or unskilfulness of carriers.Depon's Travels in South America, vol. i., p. 406, &c.' vot nas is, a dakitoa to earn m

1. An Account of a Tribe of People called KROOMEN, inhabiting a small District of the Grain Coast of Africa, between Cape Mount and Cape Palmas. By By the late THOMAS ide LUDLAM, Esq. formerly Governor of Sierra to Leone, and one of the Commissioners of African Inquiry

THE district inhabited by the Kroomen, extends, accord ing to the maps, about twenty miles along the coast, from north-west to south-east. Its extent inland is not accurately known, but it is supposed, from the best information I could procure, not to exceed the same distance, and may, perhaps, fall considerably short of it: it cannot be great, as the Krooomen have no towns except on the sea coast. The Kroo counstry lies between 4o 54′ and 5° 7′ N. latitude. Fettra-Kroo, the principal town, is in long. 7°48′ W...

The general aspect of the country is champaign, and it is very woody. It is free, however, from marshes. Its chief vegetable productions are rice, cassada, yams, plantanes, and Malaguetta pepper. The rice which it produces is valued by Europeans on saccount of its superior whiteness to what is in