The Commercial Products of the Vegetable Kingdom Part 22

The progressive increase in its exports is marked by the following return of imports into Great Britain from the island:--

Cwt.

1826 93,723 1827 186,782 1828 204,344 1829 361,325 1830 297,958 1831 485,710 1832 517,553 1833 521,904 1834 516,077 1835 553,891 1836 558,237 1837 497,302 1838 537,455 1839 604,671 1840 690,294 1841 545,356 1842 716,009 1843 696,652 1844 545,415 1845 716,173 1846 845,197 1847 1,193,571 1848 886,184 1849 893,524 1850 1,003,296 1851 999,337

_East Indies_.--Sugar is a very old and extensive cultivation in India. It would probably be within the mark, to estimate the annual produce of the country at a million of tons. An official return shows that the quant.i.ty of sugar carried on one road of the interior, for provincial consumption, is about equal to the whole quant.i.ty shipped from Calcutta--some 50,000 or 60,000 tons.

India is fast becoming a great sugar producing country, although its produce and processes of manufacture are rude and imperfect. The Coolies who return from time to time to the Indian ports, bring with them much acquired knowledge and experience from the Mauritius.

In 1825, the import of sugar from the East Indies was but 146,000 cwt., and it fluctuated greatly in succeeding years, being occasionally as low as 76,600 cwt. In 1837 the quant.i.ty imported was just double what it was in 1827. In 1841, it had reached as high as 1,239,738 cwt., and subsequently kept steady for a few years at 1,100,000 cwt.--and for the last four years has averaged 1,400,000 cwt.

_Java_.--Attention has been withdrawn, in a great measure, from sugar cultivation in Java, owing to coffee being found a more remunerative staple. The following figures serve to show the extent of its exports of sugar:--

Cwt.

1826 23,565 1827 38,357 1828 31,301 1829 91,227 1830 129,300 1831 144,077 1832 292,705 1833 151,128 1834 443,911 1835 523,162 1836 607,336 1837 820,063 1838 873,056 1839 999,895 1840 1,231,135 1841 1,252,041 1842 1,105,856 1843 1,162,211 1844 1,260,790 1845 1,812,500 1848 1,798,612 1850 1,797,874 1851 1,987,957 1852 2,090,845

In 1840, we imported from Java 75,533 cwt.; in 1841, 87,342 cwt.; in 1842, 24,922 cwt.; in 1843, 35,161 cwt.; and in 1844, about 72,000 cwt.; but most of this was only sent to Cowes, for orders, to be transhipped to the Continent.

_Philippines_.--The exports from Manila into this country in 1841, were 133,482 cwt.; in 1842, 63,464 cwt.; and in 1843, 48,977 cwt. In the fifteen years between 1835 and 1850, the export of sugar from the Philippine Islands more than doubled:--

Tons.

1835 11,542 1836 14,875 1837 12,293 1838 12,375 1839 15,631 1840 16,563 1841 15,321 1842 18,540 1843 22,239 1844 21,528 1845 24,500 1850 28,745

About a third of this is raw sugar, the rest is clayed or refined. It is singular, that though these islands belong to Spain, the export of this staple product to that country should be limited to about 600 tons; America taking about one-sixth, and England and her colonies the remainder. There is now an increased demand for the Australian colonies, consequent upon the large influx of population to that quarter.

Export of sugar from Manila in 1850.

Piculs.

To Great Britain 146,926 " Continent of Europe 50,830 " Australian Colonies 142,359 " Singapore, Batavia, and Bombay 12,749 " California and the Pacific 29,144 " The United States 77,919 ------- 459,927

The sugar cane occurs in a wild state on many of the islands of the Pacific, but in no part of the American continent, notwithstanding a contrary opinion has been expressed.

The following are the chief varieties cultivated in the West Indies, Louisiana, the East Indies, and Mauritius:--

1. Common or creole cane, so called from being introduced from the New World.

2. Yellow Bourbon.

3. Yellow Otaheite.

4. Otaheite with purple bands.

5. Purple Otaheite.

6. Ribbon cane.

My friend, Mr. L. Wray, in his "Practical Sugar Planter," considers the Bourbon, and yellow, or straw-coloured Otaheite cane, as identical, but merely altered by change of soil and climate. The yield from these cane-plants seems to be about the same in either Indies, viz., in good land about two-and-a-half tons of dry sugar per acre--sometimes three tons.

A very large species of red cane, grown at Gowhatty, in a.s.sam, is made favorable mention of for its strength of growth, early maturity, and juiciness; and Mr. Wray strongly recommends the introduction into the West Indies of another fine variety, generally grown in the Straits' settlements, where it is known by the name of the Salangore cane. He considers they would ratoon better than any other cane, and the return from it is on the average 3,600 lbs. of dry sugar to the acre.

"For my own part, I have always reckoned as an average, 3,600 lbs.

of dry sugar to the acre as the return this cane will give, on anything like good land, in the Straits, according to the present imperfect mode of expressing and manufacture; but, considering the surpa.s.sing richness of land in the West India Islands, Demerara, and Mauritius, I should not be in any way surprised to find that it would there give even three tons an acre.

The Salangore cane grows firm and strong; stands upright much better than the Otaheite; gives juice most abundantly, which is sweet and easy of clarification, boils well, and produces a very fine, fair sugar, of a bold and sparkling grain."

Much discussion has arisen on the subject of raising the sugar cane from seed, and the possibility has been universally denied among the planters and agricultural societies of the West India colonies. Mr.

Pritchard, a sugar planter of Louisiana, in the "United States Patent Report for 1850," however, states:--

"It is an error to suppose that the cane cannot be propagated from the seed. This may be the case when the seed is obtained from plants that have been produced for a number of years from buds, or eyes.

All plants that have been produced in this way for a series of years, lose the faculty of forming prolific seeds; and the sugar cane is governed by the same laws which govern the whole vegetable kingdom. It cannot, therefore, be expected to produce seeds after it has been cultivated for a great length of time."

The sugar cane is composed of water, woody fibre, and soluble matter, or sugar. In round numbers it may be stated that the proportions are 72 per cent. of water, 10 per cent. of woody fibre, and 18 per cent.

of sugar.

The fluid contents of a cane, according to Dr. Evans, contain 90 per cent. of the entire structure of the stem.

1,000 grains of sugar cane, being burnt, gave 7 grains of ash, which, on a.n.a.lysis, furnished the following components:--

Silica 1.78 Phosphate of lime 3.41 Red oxide of iron and clay .17 Carbonate of potash 1.46 Sulphate of potash .15 Carbonate of magnesia .43 Sulphate of lime 6 ---- 7.46

The following is the quantative a.n.a.lysis of a portion of soil taken from the surface of a cane field, on the Diamond estate, in St.

Vincent, West Indies: --

Alumina soluble in acids 12.87 Organic matter 11.26 Gypsum .23 Carbonate of lime 12.52 ---- of magnesia .71 Oxide of iron 8.51 Oxide of manganese .33 Insoluble silicious and aluminous matter 53.57 ------ 100.00

The sugar of the cane and grape sugar are distinguished by the following difference in their elements, as proved by a.n.a.lysis:--

Cane sugar. Grape sugar.

Carbon 12 12 Hydrogen 10 12 Oxygen 10 12 Water 1 2

There is a remarkable difference, however, between their fermentable properties. When a solution is made of the same quant.i.ties of these two sugars, in equal proportions of distilled water, it will be necessary to add eight times as much of the same ferment to induce alcoholic fermentation in the solution of cane sugar, as in that of grape sugar. Under the action of a larger quant.i.ty of ferment, cane sugar is transformed into grape sugar.

If you cut a sugar cane in two, and examine the interior part of it with a magnifying gla.s.s, you perceive the crystals of sugar as distinct and as white as those of double-refined sugar. The object of the operator should be then either to extract those crystals without altering their color, or, if that be found impracticable, to separate them from the impurities mixed with them, while the juice is in its natural state, and yet contains but little coloring matter. Instead of this, the juice is limed while all the impurities are in it. In separating the feculencies from the juice and uniting them in large flakes, lime dissolves a portion of them and forms with them coloring matter, which we all know at once discolors the juice, when lime is used in excess. Afterwards heat is applied, either in clarifiers or in the grand copper, but most of the impurities found in the juice will decompose, and burn at a degree of heat far below the boiling point, say at 120 deg. of Fahrenheit. This is shown by the thick scales continually forming in the grande. From that degree of heat the decomposition goes on in the clarifier till the juice is drawn, and continues in the grande so long as there are feculencies left. This decomposition greatly increases the quant.i.ty of coloring matter, so that, as the juice is being clarified, it loses in color what it gains in purity. And here let me show the relative value of the "grande" and of clarifiers as agents of clarification. In the grande, if it is well attended to, the sc.u.mmings are taken up as soon as they rise. A portion of them is removed before they begin to decompose, and the process goes on, so that before the juice reaches the boiling point nearly all the feculencies are removed, and the source of coloring matter is removed with them. Clarifiers reach the boiling point much quicker, and cannot easily be sc.u.mmed. The general practice is to bring them to that point without sc.u.mming, to let the feculencies separate from the juice by cooling and by rest, and to wash out the clarifiers every second or third time they are filled. Heat and alkalies acting in them upon the acc.u.mulated feculencies of one, two, or three charges, dissolve a much larger portion of those feculencies than they can possibly do in the grande. The formation of coloring matter continues during the time of rest, and accordingly planters, after repeated trials, generally agree that juice well clarified in the grande, has a lighter and brighter color, and makes better sugar than that obtained from clarifiers.

The first object of research should be to find means of clarifying the juice without creating coloring matter. It is said that presses something like those used to press cotton, have lately been successfully employed in the West Indies, instead of rollers; that the juice obtained is much purer, and that a much larger quant.i.ty of it is extracted from the cane. If so, this will be a great improvement, and the first step of the process I should recommend. From juice thus obtained, I have no doubt that all impurities less soluble than itself may be separated by mechanical means before heat and alkalies are applied, or at least with a very small quant.i.ty of alkalies. All other liquids, all fatty substances and oils, except cotton seed oil, are clarified by a very rapid process. Cane juice can no doubt be clarified by similar means, and if this were accomplished the process of sugar making would be very much simplified.

The clarified juice might then be placed in an evaporator, heated by the waste steam of the engine; then be limed and sc.u.mmed if necessary, and concentrated to fifteen or sixteen of the prese sirop; then purified by filtration through animal charcoal, if white sugar was wanted, or by rest for other qualities; and finally concentrated in vacuum pans of great power, such pans as Mr. Thomas A. Morgan, of Louisiana, now uses, and which, I am informed, are only made in America.

The superiority of the vacuum pan is not universally admitted, and we are told that in France it is superseded by open pans, similar to those called in America "Mape's Evaporators." However this may be, I cannot help believing that the vacuum pan has many decided advantages over all others. One is manifest; the sugar may be grained in the pan, and the granulation is completely under the control of the operator.

He may accelerate or r.e.t.a.r.d it at pleasure; he may carry it so far that sugar will not run from the pan, and will have to be taken out of it; he may so conduct the operation as to increase, almost at will, the size and hardness of the crystals. This last is an indispensable requisite if the practice of draining sugar in pneumatic pans should be adopted.

The atmospheric pressure is made too powerful for sugars boiled in any other manner; it breaks and destroys the crystals, and in a very few days sets the sugar to fermenting.

The pneumatic draining of sugar has many things to recommend it--the usual loss by drainage is avoided, sugar is got ready for market day by day, as it is made, and it may be bleached by pouring white syrup over it and forcing it through the ma.s.s. It is said that the process is attended with considerable loss in weight, but as all that drains from the pan may be boiled over once or twice, it is not easy to conceive how the loss can occur.

Cane juice contains many ingredients besides sugar, the princ.i.p.al of which are alb.u.men, gluten, gum, starch, resin, wax, coloring matter, and certain salts, all of which, either collectively or individually, have the power of preventing granulation, as may be proved by their addition to a syrup of pure sugar, which will then defy all attempts to make it crystallise. If, therefore, we want to make good sugar, we must endeavour to free our cane juice as much as possible from those substances.

Now, cane juice is no more the sap of the cane, than apple juice is that of the apple tree; it is the natural product of the cane, and, in all probability, would contain but a small proportion of these foreign matters if it could be expressed without being accompanied by the sap, they being the natural const.i.tuents of the last-named fluid. A patent has, I believe, been lately taken out for separating the cane juice without the sap. However, in the absence of such an improvement, much may be done by care and attention at the mill; the green bands and trash which usually accompany the canes from the field, should, therefore, be carefully removed before they are pa.s.sed through, as they contain no saccharine matter, abound in the deleterious substances already mentioned, and communicate a bad color to the juice; therefore, _the ripe cane only should pa.s.s through the mill_.

There are but few planters who have not had to contend with sour juice, and they attribute the difficulty they experience in making sugar therefrom, to the presence of acetic acid, or vinegar; but this is quite an erroneous idea, as the acetic acid is very volatile, and evaporates quickly on the application of heat, which may be proved by throwing a gallon of strong vinegar into a pan of liquor; it will do no harm, provided it be boiled before tempering; on the contrary, the effect, if it be properly done, will be beneficial, as it will promote the coagulation of the alb.u.men; it is the gum which is always formed during the acetous fermentation of sugar that prevents granulation; hence, then, acidity is strictly to be guarded against, as fermentation once commenced, it will be impossible to make good sugar, it will continue throughout the process, and even in the hogshead; so that canes should be ground as soon as possible after they are cut, and all rat-eaten and broken ones carefully excluded. Canes may, however, be kept some days without fermenting, provided they be not broken or damaged, it being, as we said before, the mixture of the sap and the cane juice that makes the liquid so p.r.o.ne to fermentation; and the mill, gutters, and everything with which the juice is likely to come in contact, should be kept carefully clean, and whitewashed immediately after, and the whitewash removed before use, as acetate of lime being an exceedingly soluble and deliquescent salt, will not improve the quality of the sugar; whilst the gutter should be short, and sheltered from the sun's rays, they having the effect of greatly expediting chemical action.