Part 6

The construction of Mr. Clerihew’s heating apparatus is simple, and a moderate supply of fuel has a considerable effect in raising the temperature of cold damp air before it is brought into contact with the coffee through which it is drawn by the aid of the fans. This heated air becomes diffused throughout the whole of the chamber, which extends beneath the ground-floor in such a manner that no portion of the coffee which is on that floor can be free from its influence.

The fans at Rathoongodde are much more powerful than those in common use, the peculiarity in the shape of the blade giving them a great advantage as air-moving machines, in so far as the indraught is concerned, whilst one-half of the periphery being open a ready exit is afforded for the discharge of air. In the ordinary fan, if a smoking match is applied to any part of the indraught opening, the air will be seen to flow towards a neutral point in the centre of the fan, following a spiral direction, and thence in the periphery of the fan.

In Mr. Clerihew’s modification of the blade each film of air, so to speak, flows into the fan directly, until it impinges on the curvilinear part of the blade, and from that point is thrown at a right angle towards the periphery. The column of air being thus less distorted in its progress, there is not only a greater quantity discharged, but much less power is consumed in effecting that discharge--in the common fan it is evident, from the circumstance of the air flowing to an apex, that a great amount of power is wasted in producing the increased velocity with which a column of air equal in volume to the two ingress openings of the fan must pass so contracted an area before it is discharged; hence it is that the fan, as an air-moving machine, has been considered unequal to the screw.

The enclosed space of the coffee-curing house at Rathoongodde has an area in the cross section of 100 superficial feet, it is 70 feet long, and a pair of fans are placed at one end. Repeated experiments have shown that, when the fans make 100 revolutions per minute, a cloud of smoke travels to them from the centre of the enclosed space (a distance of 35 feet) in precisely 15 seconds, hence we have 100 × 35 = 3500 cubic feet of air discharged in a quarter of a minute, or 14,000 cubic feet per minute; a screw of nearly seven feet in diameter would be required to discharge the same amount of air, and the cost of it in England is 84 guineas, whilst the pair of fans made and fitted up at Rathoongodde cost under 9_l._

In the centre of the enclosed space, with a depth of four feet of coffee in the upper floor, the flame of a candle is blown to a right angle when the whole power of the fans is put on that floor; near to the fans it is extinguished, the air moving forward with a uniformly accelerated velocity from the farther end towards the fans, owing to the constant accessions made by the air entering the enclosed space throughout its whole length.

It has already been mentioned that the only entrance of air into the air-chamber beneath the ground-floor is by the opening in which the stove is placed, consequently, when this opening is closed by a damper, it is obvious that the whole power of the fans is exerted on the mass of coffee which is being cured on the upper floor, and that the division of this power may be regulated at will by more or less obstructing the entrance of air to the air-chamber by the damper. The upper floor is not supposed to be an air-tight apartment, but as the chief entrance of air is by the two doors in the end, its influx may be so far obstructed by closing them as to throw the greater part of the power of the fans on the coffee which is on the ground-floor, when this is required. Again, since it is obvious that, in wet weather, when the atmosphere is fully saturated with moisture proportionate to its temperature, it becomes a desideratum to introduce a portion of the artificially heated air into the vacant space which is over the coffee in the upper floor, so that the air which passes down through that coffee may have an absorbing tendency; this is accomplished by shutting the doors of the upper floor and throwing open the top-covering of the fan. By this means one-half of the air which is drawn from the stove is thrown in above the coffee in the upper floor, whilst the other half is discharged altogether. This infusion of heated air would on many occasions be attended with benefit, but the advantage will naturally depend on the comparative state of dryness of the coffee on the two floors.

In having recourse to these practical modifications some little judgment and observation are of more service than precept. It will be found, for instance, that if the coffee in the upper floor approaches the dry stage, it is better in wet weather to shut the doors of that floor as well as the tops of the fans, so that only a small flittering of air sufficient to ward off the first stages of decomposition may pass through that coffee, whilst the wet coffee below has the full benefit of a more rapid circulation of absorbent air.

Attention may now be directed to the practical results which these arrangements have afforded in the curing of coffee.

The coffee in the upper floor, as the crop advanced, gradually increased in depth until it stood at four feet all over the floor. When at this depth, with the fans making 100 revolutions per minute, the flow of air was quite sensible to the hand placed on the surface of the coffee, and was rendered apparent by the smoke from a match following the direction of the air; at the same time the rarefaction of the air within the enclosed space was so very slight as barely to be appreciable by a very delicate mountain barometer, though it had the effect of causing the door to shut with a slam; thus showing that a slight rarefaction of the air is sufficient to disturb the balance of atmospheric pressure, even when acting through a medium of coffee of considerable depth. The current of air thus established continued to flow without interruption until the fans were stopped.

A cold glass tumbler taken into the store in a warm day, when the fans were not in motion, became instantly dimmed and wet by the precipitation of moisture from the internal air. When another glass was taken into the store, one minute after the fans were put in motion, it remained clear, without a trace of moisture.

A very satisfactory result soon showed itself, viz. that whilst the temperature of the air as it entered the moist coffee was 80° in a warm day, the temperature of the coffee itself, as indicated by an immersed thermometer, was only 58°; the wet coffee being invariably coldest when the air that was made to pass through it was warmest. This paradox admitted of easy explanation, when it was considered that each bean of undried coffee was under similar circumstances to evaporating vessels of water placed in a draught of warm air for the purpose of cooling the water. The cold thus produced was, therefore, the necessary concomitant of the evaporation that was going on, and the difference between these temperatures afforded a measure of the drying power in different states of the weather. The circumstance of the hot air lowering the temperature of the coffee was also favourable in another point of view, seeing that it has been shown that heat is one of the conditions which promotes mouldiness, or the germination of fungi.

Every bushel of parchment coffee contains half a cubic foot of air, a fact ascertained by a bushel which took thirty-three measures of water to fill it. When full of newly-washed coffee it took thirteen of these measures of the water to displace the air from the interstices of the beans without overflowing, so that we have 13--33 of air in a bushel of coffee; in other words, half a cubic foot. Hence, the fans in use are capable of giving a fresh atmosphere to 28,000 bushels of coffee every minute, or in the same time four fresh atmospheres to 7000 bushels.

During a continuance of nearly three months of wet weather which occurred at one crop time, the coffee in the curing-house dried very slowly, but was kept in a perfectly fresh and sweet state without the intervention of any manual labour, further than in depositing each day’s increase in the lower floor to dry off the surface water, and removing that of each previous day to the upper floor, where it was spread on the top of all the coffee that had previously accumulated. These three months of wet weather were succeeded by a fortnight of very dry weather, and, on examining the coffee at the end of that period, it was found to have reached the dry horny stage at which it is usual to despatch it from the estate to Colombo, for the purpose of being peeled and shipped. On examining the beans they were found to be of that clear colour which distinguishes coffee carefully cured in small quantities, with the advantage of the most favourable weather. Under like circumstances, viz. during such a continuation of wet weather, it would have been impossible to preserve the coffee free from more or less mustiness of smell, by manual labour employed in the usual way, whilst at the same time the expense of storework would have been more than fourfold. The whole expense of the storework, viz. pulping, washing, curing, and storing the Rathoongodde coffee, amounted to 2¼d. per cwt., and when it is considered that during crop time the value of every man’s labour is greatly increased, it is an object, as far as possible, to substitute mechanical contrivance for manual labour, so that all hands may be employed in gathering the crop as it ripens.

Every planter knows that when coffee is spread out in a single layer on the floor of his store, it becomes dry after a time, and is well cured without any further attention on his part; but it is impossible to devote sufficient space for this purpose without incurring an expense which would be quite incompatible with his circumstances. When, however, coffee is thus spread out in a single layer, it is obvious that the reason why it requires no attention is, because the beans being freely exposed to the atmosphere, there is naturally a constant change of the air by which they are surrounded; the same air is not sufficiently long in contact with the beans to excite the first action of decomposition, and the absorption of oxygen is not accomplished. Presuming, however, that it were so, the subsequent actions could not take place, for the products of the first action, viz. carbonic acid, heat and watery vapour, would immediately make their escape and be dissipated by the atmosphere, which is precisely what takes place when, by mechanical means, a draught of air is carried through a _mass_ of coffee. Hence, it is evident that the requirements of space are overcome by the adoption of this plan, and that a great mass of coffee is placed under conditions similar to those by which a single layer is influenced when exposed to a natural draught of atmospheric air.

SECTION XIV.

CULTIVATION IN SOUTHERN INDIA.

Southern India is becoming as celebrated for its coffee, as Northern India for its tea. We find that the exports of coffee from Madras have increased considerably during the last five years, and there is every reason for supposing that Southern India will shortly become the chief coffee-producing country of the world. We have no idea of the number of acres of land under coffee cultivation in the Madras Presidency, but it must be very large, for after its local wants have been supplied, coffee to the value of half a million sterling is exported.

In 1858-59 the shipments were 7,288,421 lbs. to foreign ports, and 4,083,917 lbs. to Indian ports. In 1862-63 the shipments were 16,292,238 lbs. to foreign ports, and 3,976,766 lbs. to Indian ports.

Though some parts of India are well adapted to the culture, it is not yet so extensively cultivated as might have been expected from the vicinity of its Arabian sites to the Malabar coast. There, however, some excellent coffee is grown, as well as in the hilly regions of Mysore and on the slopes of the Neilgherries, and some of these are of such good quality, and so carefully prepared, as to bring the same price as Mocha coffee. Some very good specimens of coffee have also been produced in the interior of India, as in the district of Chota Nagpore, where the culture might apparently be greatly extended, and be of great benefit for consumption in that part of the country.

According to local tradition, the coffee-plant was introduced into Mysore by a Mussulman pilgrim, named Baba Booden, who came from Arabia about two hundred years ago, and took up his abode as a hermit in the uninhabited hills in the Nuggur Division named after him, and where he established a college, which still exists, endowed by government. It is said that he brought some coffee-berries from Mocha, which he planted near to his hermitage, about which there are now to be seen some very old coffee-trees. However this may be, there is no doubt that the coffee-plant has been known in that neighbourhood from time immemorial, but the berry has never come into general use among the people for a beverage. It is only of late years that the coffee trade of these districts has become of any magnitude, or that planting has been carried to any important extent. The export of coffee from British India, which in 1851 was only 3239 tons, had increased in 1861 to 8535 tons; about one-fourth of this is shipped from Bombay, and nearly all the remainder from Madras.

More than thirty years ago a few Europeans were engaged in coffee planting near Chickmoogloor, a few miles from the Bababooden Hills. About twenty years ago the plantation producing the well-known coffee called “Cannon’s Mysore,” and others, on the Memzera, or “Bad Mountain,” was commenced by two enterprising gentlemen. The success of these has induced many more Europeans to plant coffee there, and the consequence is that the coffee trade of Mysore bids fair to emulate that of Ceylon. It has given, also, an example to other parts of India, and the plant originally taken from the Bababooden Muth is now extending over tens of thousands of acres in Coorg, the Wynaad district, the Neilgherry Hills, and along the Western Ghauts, north and south.

In Mysore the number of European coffee-planters has increased to about thirty, while the number of native planters is estimated at between three and four thousand.

The average produce per acre in Mysore is probably not half that of Ceylon. Some attempts have been made to cultivate coffee in the open country, but without success; it seems to require forest land and considerable elevation and moisture. “Cannon’s Mysore” is grown on a range of hills from 3500 to 4000 feet above the sea, having the benefit of the south-west monsoon, which very seldom fails at all, never entirely, and of the tail-end of the north-east monsoon. This elevation gives a pleasant climate, well suited to Europeans.

Several species of the genus Coffea (_C. alpestris_, _C. grumeloides_, and _C. Wightiana_) are indigenous to the Neilgherry Hills.

A berry, generally one which has itself fallen ripe from the tree, is put into the ground, usually in a nursery plot, though some planters prefer to place the seed in the identical hole which is to be its future situation. The nursery plan is, however, generally adopted, and here the young plant, which shoots up in about a month after it is sown, is allowed to remain until about sixteen months old. It, or rather we will say they, for hundreds and thousands are generally dealt with at once, are transplanted to holes which have been carefully prepared for them on the soil which is to be their future location. These holes are generally two feet cube, and many good planters prefer them even deeper; in this the plant is carefully placed and covered around, and in eighteen months from that time, _i.e._ about three years from the time the berry was first planted, our small coffee-tree begins to bear fruit, the first crop being of course very scanty.

The berry is picked from November to the end of February, by any number of men, women, and boys which can be collected, and who are paid by the quantity they pick, some expert hands earning a good deal.

The berry collected is carried to the house of the estate, and there having been weighed, is thrown into what is called a cherry loft, a wooden chamber, alongside of, but a little higher, than the place containing the pulper. From this cherry loft to the pulper the coffee is washed by a stream of water, which carries it along a trough so arranged as to catch and impede any stones or heavier materials from entering the pulping machine. These heavier materials sink to the bottom of the trough, and the buoyant coffee-berry, floating on the surface, is borne to its destination.

The object of the pulper is to remove the fleshy capsule from the berry, and this being accomplished, the coffee passes on in one direction, whilst the pulp, by a clever arrangement of the mechanism of the instrument, is pushed away in another. The berry is now thrown into a vat and allowed to ferment, until the remaining mucilaginous substance adherent to the parchment covering is easily washed away by water.

This accomplished, it is thrown on open exposed places, called barbecues, and allowed to dry in the sun. This takes about twelve days, when it is packed in gunny (jute) bags, placed upon bullocks, and despatched to the coast.

There it is what is called garbled, that is, having been once more exposed to the sun and thoroughly dried, it is placed in circular troughs, and over it large heavy wheels, shod with iron nails, are made to revolve. This removes what is called the parchment skin, leaving the berry now covered only with a beautifully fine coating, the silver skin.

It is then, by a number of women employed for the purpose, carefully sized; after this, passed through a pea-berry mill, the object being to separate the round pea-shaped berry from the flatter, the former being much more prized, and fetching a higher price in the market, though why, it is difficult to say, as it makes no better coffee than the other; and as it has to be deprived of its form by roasting and grinding before it comes to table, the advantage of its pea-shaped figure is, to say the least of it, somewhat obscure.

There is likewise separated from the rest what is called “triage,” the broken and otherwise defective beans, which are also packed by themselves, and which again, we believe, though selling more cheaply, are found to make quite as good an infusion for a beverage as their more aristocratic friends the pea-berries. However, pea-berries, flats, and triage, are all ultimately packed in square wooden boxes and shipped to England, where it is sold, roasted, ground, and drank.

In Wynaad, in the close of 1863, there were 93 coffee estates, covering 50,000 acres, of which about 15,000 acres were planted; 6100 acres had trees over two years old on them. There were also about 3600 acres under culture with coffee by the natives. Wynaad is an elevated plateau, rising somewhat abruptly from the western or Malabar side, but sloping more towards the Mysore or easterly side.

The quantity of coffee exported from Tellicherry during the official year ending April, 1862, was 58,500 cwt., of which about 30,000 cwt. is supposed to have come from Wynaad, the rest from Coorg. 8 cwt. of coffee per acre is considered an average yield in Wynaad, 10 cwt. a good crop.

SECTION XV.

BOURBON, JAVA, AND THE EAST.

It was from Beit-el-Faguil, the European factory near Mocha, that the coffee-tree was transported to the island of Bourbon, in the year 1718, and it is remarkable that the islanders recognised the plant as natural to their own country, and brought the astonished importers abundance from their native mountains. In Bourbon they distinguish four varieties of the coffee-plant.

1. The Mocha, which is very delicate, for the plants degenerate and often perish after a good crop.

2. The Levoy, which is more hardy, but the coffee is inferior in quality.

3. The Myrtle, a variety of the Mocha, very hardy, and yielding abundant crops.

4. The Marron, or wild coffee, with such bitter and narcotic properties that it can only be used by admixture with the berries of one of the other varieties.

JAVA.--In Java, coffee is a government monopoly, and the planters bring their coffee to a central government depôt for sale at a fixed price. The island exports about 1,250,000 cwts. of coffee annually. Java coffee has lost much of its former repute from being largely saturated with moisture, artificially to the extent of 14 per cent.; this increases the weight, but must injure the quality in transport.

At the Paris Exhibition of 1855, the Netherlands Commercial Association contributed a very varied collection of two dozen varieties of coffees from the Dutch government possessions in Java, under the following classification: Brown, clear brown, deep yellow, yellow, yellowish, white, whitish, pale of Havana kind, blue, fine green, handsome green, green, greenish, mottled green, deep green West India kind, green West India kind, pale green West India kind, dark Demerara kind, green Demerara kind, deep grey, triage, common black, greenish Menado, and white Padang. The Netherlands Society sell about 1,000,000 bags or bales of coffee annually.

The following were the exports of coffee from Java in 1862:

piculs. To Holland on private account 128,047 To other countries 165,116 By the Netherlands Trading Company 877,241 --------- 1,170,404

The position of the coffee trade of Java is shown in the figures annexed, for five years:

EXPORT AND VALUE OF COFFEE.

tons. value. 1858 66,575 £2,614,505 1859 59,769 2,565,137 1860 54,638 2,486,115 1861 61,783 2,850,518 1862 63,286 3,465,747

Three kinds of Java coffee are commonly brought to Europe--Jacatra (usually sold as Java), Cheribou, and Samarang. The first is the best, the second is generally a little lighter colour and of somewhat inferior quality, and the third has yellowish brown, or green, flattened beans. What is generally sold in the Dutch markets as Samarang is, however, simply a kind of “triage,” with black beans of a coarse flavour.

SIAM.--On the hilly districts of the east coast of the Gulf of Siam the cultivation of coffee is carried on to a limited extent, and some very fine samples of Siam coffee were shown at the International Exhibition of 1862, sent me by Messrs. Markwold and Co., and by Sir Robert Schomburgk, the British Consul-General.

SUMATRA is one of the worst kinds of coffee received from the Eastern Archipelago. The beans are large, dark yellow or brown, and occasionally even black, and the flavour varies considerably. The production in Sumatra averages about 5 to 6,000,000 lbs., but has often been double that amount.

CELEBES.--With the exception of Menado, which has large beans of a pale greenish or yellow colour, Celebes coffee is greatly inferior to Java, and it is questionable whether the colour when brought to market is not given by artificial means. The production is about 1,000,000 lbs.

PHILIPPINES.--Manilla coffee is one of the best of the Eastern kinds, and quite equal to Java. The average production is about 3,000,000 lbs. The beans are medium-sized, and of a pale greenish colour. The coffee is shipped in bags of about 150 lbs., or in cases or chests of 200 lbs. to 300 lbs.