In Indio, where the cultivation would doubtless he attended with great success and profit, all trace are good proteetors except those which change their hark; the best are the mango (.11fangifera indica), jack (Artocarpus integrifolia), ouatier (Bomb= malabAricum), and physie-nut (Curcas purgans tfatropha Cureas]). The last muat not be planted alone, as it sheds its leaves when the vanilla is in full beariug. Perhaps none is better than Erythrina indica, already widely utilized as a ahade-tree in Eastern agriculture. The best planting-aeason is March-May. The most auitable tiers are tho leaves of the vacoua (Pan,tanus utilis), which will have rotted and fallen off by the time that the plants are able to dispense with them.
Spontaneous fecundation of the plant is comparatively rare, as the labellum or upper lip of the etigmatic orifice completely covers the female organ, and the anther reats on that valve of the stigma. In countries where the plant is left to itself, a length of 12-26 in. of vine only produces one pod, though the number of flowers in that length may he 40. All may be artificially fecundated by slipping away the labellum from beneath the anther, and so bringing that organ into direct con tact with the stigtna ; but only the finest flowers (about doz.) on each buach should be fecun dated, or the plant would die of exhaustion. Fecundation is known to be assured when the flower ie persistent and dries at the end of the fruit. The remaining buds should -be cut off.
As already observed, the fecundated flower decays at the extremity of the ovary, and, after some days, falls off; leaving the persistent gynostem attached to the fruit, which continues to grow for a month, but must be left on the stem for 6 months longer to allow it to ripen. Each pod should theu be out off eeparately, as it matures, instead of detaching the entire bunch, as is done in some countries. The only certain indication of maturity is the crackling produced when tbe pod ia pinched between the fingers ; the apple-green or greenish-yellow colour is not a sufficiently reliable sign. It ie quite as important to avoid gathering the pods too soon as too late. If unripe, the pro duct will lack fragrance, eoleur, &c. ; if over-ripe, the pod will be yellow at the end, und, if not already split, ie apt to become so in curing.
The odour of vanilla does net pre-exist in the ripe fruit, but is developed by fermentation. Wheu a pod is allowed to remain on the plant, it splits into two unequal pat te, becoming first yellow, then brown, and finally black. While it is drying, it exudes an unctuous liquid of dark-red colour called " balsam of vanilla," and, when quite dry, becomes brittle and devoid of all perfume. The following are the various processes for curing vanilla. In Guiana., the beans are placed in ashes, and there left until they begin to shrivel ; they are then wiped, rubbed over with olive-oil, and, their lower end having been tied, etre hung in the open air to dry. In Peru, they are dipped into boiling water, tied at the end, and hung in the open air for 20 days to dry ; they are then lightly smeared over with castor-oil, and a few days later are tied up in bundles. In Mexico, as soon as gathered, the beaus are placed in heaps under a shed, protected from sun and rain, and, in a few days, when they begin to shrivel, are submitted to the " sweating " proceas. This is carried on in two different ways, according to the state of the weather. If it happens to be warm and fine, the beans are spread out iu the early morning on a woollen blanket, and exposed to the direct rays of the sun. At about
noon or 1 r.m., the blanket is folded around the beans, and the bundle is left in the sun for the re mainder of the day. In the evening, all the vanilla is enclosed in air-tight boxes, so that it may sweat the whole night. The next day, the beans are again exposed to the direct action of the sun. They then acquire a dark coffee-colour, the tint being deeper in proportion to the success of the sweating operation. Should the weather be cloudy, the vanilla is made into bundles, and a number of these axe packed together into a small bale, which is first wrapped in a woollen cloth, then in a coating of banana leaves, and the whole, enclosed in a mat, is firmly bound, and sprinkled with water. The bales containing the largest beans are now placed in an oven heated to 60° (140° F.). When the temperature of the oven has fallen to 45° (113° F.), the smaller beaus are introduced, and the oven is closed tightly. In 24 hours, the smaller beans are taken out ; and 12 hours later the larger oues. During this process, the vanilla has " sweated," and acquired a fine chestnut colour. The delicate operation of drying has now to be commenced. The beans are spread on matting, and exposed to the sun every day for about two months. When the drying is nearly complete, sun-heat is no longer needed, and they are spread out in a dry place until the necessary degree of desiccation is arrived at ; they are then tied up in small packets. In the Rdunion process, the beans are sorted according to length, to be scalded. The long ones are steeped in water heated to 90° (191° F.) during 10 seconds, the medium size during 15 seconds, and the short ones fully & minute. They are then exposed to the sun between two woollen blankets until they acquire the characteristic chestnut colour. After this exposure, which may last 6-8 days, the beans are spread out under sheds to dry gradually. The sheds in this colony being roofed with zinc, they really constitute drying stoves, through which a current of hot air continually circulates. This desiccation takes about a month, during which time the only care necessary is to turn the beans frequently, so that they dry evenly. At the moment when it is found that the beans may be twisted easily round the finger without cracking—that is to say, when they have acquired a degree of dryness which can be known only by experience—the operation requiring the most minute and vigilant care commences : this is termed the " smoothing " process. The operator must pass every bean between his fingers, and repeat this frequently, for, on drying, the beans exude from their entire surface a natural fatty oil. It is to this oil, which exudes as the fermentation proceeds, that the lustre and suppleness of the bean is due. When sufficiently dry. they are tied up in bundles of uniform length. In this manner, the three commercial sorts are obtained :—(1) " Fine " : 8-11 in. long, nearly black, unctuous, glossy and clean looking ; these soon become covered with frost-like crystals. (2) " Woody " : 6-8 in. long, lighter in colour, more or less spotted with grey, not glossy ; these are the pods gathered in an unripe condition ; they crystallize very little, if at all. (3) " Vanillons," of which there are two sorts, those obtained from short but ripe fruit, which are excellent, and frost well ; and those from abortive and unripe fruit, whose perfume is simply the result of absorption from the fine beans with which they have so long been in contact.