The Commercial Products of the Vegetable Kingdom - Part 28
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Part 28

The Messrs. Grar were so thoroughly satisfied with it, that when I was there they had taken down their original apparatus, and were re-erecting it on such a scale as to work up all the mola.s.ses by it, equal to almost five tons of sugar daily. Owing to this circ.u.mstance, I had not an opportunity of seeing the process on a working scale, but was shown the whole proceedings in the laboratory.

The only difficulties I see in applying this process at once to the cane juice, are the large quant.i.ty of barytes required, the expense of re-burning it and the entire change in works that would be necessary before it could be introduced. The advantage would be, the obtaining the whole sugar contained in the juice, free from all impurities, consequently white, and in the shape of a syrup marking 20 to 23 degrees instead of 8 or 10 degrees, thus saving fully half the evaporation now required. The sugar made in this way, I was told, contains no trace of barytes.

To show you the degree of economy practised in such establishments in France, I may mention that the washings of the saccharate of barytes are sold to the makers of potash and soda, who make a profit by boiling them down to obtain what salts they contain.

The carbonic acid is obtained by the combustion of charcoal in a closed iron furnace into which air is forced by an air pump, requiring, I believe, about one horse power. From the top of the furnace a pipe leads into a washing vessel, from which the gas is led into the bottom of the vats by pipes.

At Valenciennes I met with Mr. Cail, who, beside being an engineer and machine-maker, is interested in sugar-making, both in France and in the West Indies, and most thoroughly understands the subject. He invited me to accompany him to Douai, to see a new set of works which had been set agoing this month. I was of course too glad to accept his invitation, and started with him at six next morning, reached Douai at eight, and then proceeded to the works, which are a few miles out of town. In this work a new process is also employed; it is that of Mr. Rouseau, and is said to answer well. The beet root juice, as soon as possible after expression, is thrown up by a montjus into copper clarifiers with double bottoms, heated by steam at a pressure of five atmospheres. To every hundred litres of juice (=22 gals.) two kilogrammes of lime are added (about four and a half pounds English weight). The lime is most carefully prepared and mixed with large quant.i.ties of hot water till it forms a milk perfectly free from lumps. The steam is turned off, and the juice heated to 90 deg. A complete defecation has taken place, the steam is shut off, and the juice left a short time, to allow the heavier impurities to subside. It is then run off in the usual manner, undergoes a slight filtration through a cotton cloth placed over a layer of about four inches thick of animal charcoal, and runs into a second set of copper vessels placed on a lower level than the clarifiers; these vessels are heated by means of a coil of steam piping sufficient to make them boil. A second pipe pa.s.ses into them, making a single turn at the bottom of the vessel; this is pierced on the lower side with small holes, through which a stream of carbonic acid gas is forced.

This decomposes the saccharate of lime, which has been formed in consequence of the large excess of lime added to the clarifiers.

The lime is precipitated as carbonate. When precipitation has ceased, steam is turned on, and the whole made to boil; this expels any excess of carbonic acid; the liquor is then run off, undergoes a similar partial filtration to that mentioned above, and is then pa.s.sed through the charcoal filters to be decomposed. The sugar made by this process, directly from the beet-root juice, is nearly white.

The mola.s.ses is re-boiled as often as six times; each time undergoing a clarification and filtration through animal charcoal.

And the proceeds of the last re-boiling is certainly in appearance not worse than a great deal of muscovado I have seen shipped from Trinidad.

In this work there are about 150 people employed. The work goes on night and day, one gang replacing the other. The whole evaporation is done by two vacuum pans, each 6 feet in diameter, 80,000 kilogrammes of beet-root are used daily, from which about 6,000 kilogrammes of sugar are obtained, equal to about 6 tons English weight.

In these and every other works I visited--eight in all--the centrifugal machines were in use, and had in most cases been so for two years; those lately made have been much simplified in construction, and work admirably. Cail & Co., of Paris, are the makers; their charge is 3,000 francs for each machine (120 stg.).

They require about one and a half horse power each. As they are wrought in France, one machine is about equal to work off a ton and a half of sugar daily, working all the 24 hours. Mr. Cail recommends a separate engine for those machines; so that they can be used at any time, independent of the other machinery. The charge put into a machine is about 80 kilogrammes, from which about 30 to 35 kilogrammes of dry sugar is obtained; the calculation is, I believe, 40 per cent. I weighed some of the baskets of sugar taken out after drying, and found them 35 kilogrammes. Sugar intended for the machine is never concentrated beyond 41 degrees Baume; that made from the juice direct is allowed 18 to 34 hours to crystallize, and is put into the machine in a semi-liquid state; the motion at first is comparatively slow; in about three minutes the sugar appears nearly dry; about three-fourths of a gallon of brown syrup is then poured into the machine whilst in motion, and the speed brought up to its highest, about 1200 revolutions a minute; in 3 or 4 minutes more the machine is stopped, the sugar scooped out and thrown into baskets, the inside of the revolving part, and especially the wire cloth, carefully washed with a brush and water, and a fresh charge put in. The whole time betwixt each charge is about 15 minutes. From the large proportion of mola.s.ses you will see very plainly that those who do not intend to re-boil, need not think of centrifugal machines. The sugar dried in this way is not altogether white, but has a slight greyish yellow tinge.

Of the other sugar works which I visited, the only one of peculiar interest was that of Mr. Dequesne, near Valenciennes. Here the roots are first cut into small pieces by an instrument similar to a turnip slicer, then dried in a species of kiln, and stored up till required. In this way I was told beet-root could be preserved with very little deterioration for a full year, and this enables Mr.

Dequesne to go on making sugar all the year round. When the sugar is to be extracted, the dried cuttings are put into a series of closed vessels connected by pipes, and by a system of continuous filtration of warm water through these vessels the solution of sugar is obtained, of a density equal, I believe, to 25 degrees Baume; it is a good deal colored, and requires filtration through animal charcoal. Mr. Dequesne informed me that for five years he had been unable to make this mode of sugar-making cover its expenses, owing to the loss occasioned by fermentation taking place in the beet-root; but that he has now entirely overcome that difficulty; by what means I was not told.

The number of macerating vessels is fourteen, ten of which are working at a time, the other four filling and emptying.

A greater number of vessels, Mr. Dequesne thinks, would be advantageous, as cold instead of hot water could then be employed.

He thinks a similar plan might be introduced in the West Indies with great advantage, and that by employing the proper means to prevent fermentation the sun's heat would be quite sufficient to dry the cane slices.

Mr. Dubranfaut and Mr. Rouseau's processes are patented in England.

The terms for the use of the former would, I was told, be made so moderate, as to offer no obstruction to its being used in the colonies. What Mr. Rouseau's terms are I could not learn.

There are now 288 works making beet root sugar in France, and over 30 in Belgium. The same manufacture is rapidly spreading in Germany and Russia, and is now being introduced in Italy. Whilst at Valenciennes, I learned that two English gentlemen had just preceded me in visiting the works in that neighbourhood, mentioning that they had in view introducing the beet root sugar manufacture in Ireland.

The sugar crop of France was last year over 60,000,000 of kilogrammes (60,000 tons). For two years _Belgium has been exporting_ to the Mediterranean. One maker told me that he had last year exported a considerable part of his crop. It would therefore appear, that even beet root sugar can compete in _other than the producing country_ with the sugar of the tropics--a most significant hint that, unless the cane can be made to yield more and better sugar than is now generally got from it, there is some risk of its being ultimately beaten by the beet root, the cultivation of which is now carried on with so much profit that new works are springing up every year, in almost every country of the continent.

In going through the French works, I made inquiries as to how far the procede Melsens had been adopted, and was everywhere told it was a total failure. I, however, determined to see Mr. Melsens and judge for myself how far it might be applicable to the cane, even if a failure with regard to the beet root. I, therefore, went on to Brussels, enclosed my letters of introduction and card, and received in return a note, appointing to meet me next morning. I found him one of the best and most obliging of men. He immediately offered to go over some experiments on beet root juice with me at his laboratory, where I accordingly spent the greater part of two days with him, and went over a variety of experiments; and from what I saw and a.s.sisted in doing, I feel strongly inclined to think that, notwithstanding the French commission at Martinique report otherwise, some modification of Mr. Melsens' process may be most advantageously employed in making cane sugar if not as a defecator, at least to prevent fermentation, and, probably, also as a decolorising agent.

Mr. Melsens showed me letters he had received from Java from a person with whom he had no acquaintance, stating that he had used the bisulphate of lime with complete success; and whilst I was with him he again received letters from the same person, stating that by its use he had not only improved the quality of sugar, but had raised the return to 9 per cent. of the weight of cane. From the letters which I saw, the process appears to have been tried on a very large scale, with the advantage of filters and a vacuum pan.

Where the old mode of leaving half the dirt with the sugar, and boiling up to a temperature of 340 degrees or thereby, is continued, I fear there is not much chance of either bisulphate or anything else making any very great improvement.

The use of bisulphate of lime is patented in England and the colonies, but I believe I may state the charge for the right of using it will be made extremely moderate.

The points which appeared to me worthy of remark in visiting the beet-root sugar works are, the extreme care that nothing shall be lost--the great attention paid to cleanliness in every part of the process, besides the particular care given to defecation. No vessel is ever used twice without being thoroughly washed. Such a thing as the employment of an open fire in any part of the manufacture is quite unknown. Everything is done by steam, of a pressure of from 4 to 5 atmospheres. In the more recently started works, the evaporation is entirely carried on in vacuum. In some of the older works copper evaporators, heated by coils of steam piping, and having covers, with chimneys to carry off the vapor, are still used; but of the eight works I visited I only saw them in use in one of them, and they are nowhere used excepting to evaporate to the point when the second filtration takes place.

The coolers I saw were invariably made of iron, and varied in depth from 2 to over 6 feet. These very deep vessels are used for the crystallization of sugar, made of the fourth, fifth and sixth re-boilings of mola.s.ses, which requires from three to six months.

One thing struck me forcibly in going over the French and Belgian works; it was the extreme liberality with which I was allowed to go over every part of them; to remain in them as long as I pleased; had all my inquiries answered, and every explanation given; in most striking contrast to the grudging manner in which I have been trotted over some of the refineries in England, as if those who showed them were afraid I should gain any information on the subject of their trade.

Mr. H. Colman, speaking of the agriculture of the Continent, gives some information he obtained on the comparative cost of producing beet and cane sugar. A hectare (two and a half acres) produces, in the Isle of Bourbon, about 76,000 kilogrammes (a kilogramme is nearly two and one-fifth pounds) of cane, which will give 2,200 kilogrammes of sugar, and the cost for labor is 2,500 francs. A hectare of beet root produces 40,000 kilogrammes of roots, which yield 2,400 kilogrammes of sugar, and the expense of the culture is 354 francs. The cost of the cane sugar in this case is 27 centimes, and of the beet sugar 14 centimes only, per kilogramme.

These are extraordinary statements, and will be looked at by the political economist and the philanthropist with great interest. There are few of the northern states of Europe, or of the United States, which might not produce their own sugar; and when we take into account the value of this product, even in its remains after the sugar is extracted, for the fattening of cattle and sheep, and of course for the enrichment of the land for the succeeding crops, its important bearing upon agricultural improvement cannot be exaggerated.

According to M. Peligot, the average amount of sugar in beets is 12 per cent.; but, by extraction, they obtain only 6 per cent. The cane contains about 18 per cent. of saccharine matter, but they get only about 7. The expense of cultivating a hectare of beets, according to Dombasle, is 354 francs. An hectare of cane, which produces 2,200 kilogrammes of sugar, in the Island of Bourbon, and only 2,000 in French Guiana, demands the labor of twelve negroes, the annual expense of each of whom is 250 francs, according to M. Labran.--(Commission of Inquiry in 1840.)

Sugar has become not only an article of luxury, but of utility, to such a degree, that a supply of it const.i.tutes an important article of importation, and is of national consequence. For sugar the world has. .h.i.therto relied on the cane, with the exception of some parts of India, where the sugar palm yields it much more cheaply. The sugar cane is, however, a tropical plant, and, of course, its cultivation must of necessity be limited to such hot countries. France, during the wars of Napoleon, shut out from her Indian possessions or deprived of them, commenced making sugar from beets, and it proving unexpectedly successful and profitable, it has as we have just seen, extended not only over that empire, but nearly the whole of continental Europe, where it forms an important item in their system of cultivation and profit. The manufacture has been attempted in the United States; but though the facts of the ease and certainty with which the beets may be grown and their great value for stock has been fully ascertained, still little progress in the production of sugar from them has been made there.

MAPLE SUGAR.

There are few trees in the American forest of more value than the maple (_Acer saccharinum_). As an ornamental tree, it is exceeded by few; its ashes abound in alkali, and from it a large proportion of the potash of commerce is produced; and its sap furnishes a sugar of the best quality, and in abundance. It likewise affords mola.s.ses and an excellent vinegar. In the maple the sugar amounts to five per cent. of the whole sap. There is no tree whose shape and whose foliage is more beautiful, and whose presence indicates a more generous, fertile, and permanent soil than the rock maple: in various cabinet-work its timber vies with black walnut and mahogany for durability and beauty; and as an article of fuel its wood equals the solid hickory. Its height is sometimes 100 feet, but it usually grows to a height varying from forty to eighty feet. It is bushy, therefore an elegant shade tree.

The maple is indigenous to the forests of America, and wherever there has been opportunity for a second growth, this tree attains to a considerable size much sooner than might be imagined. In the course of ten or fifteen years the maple becomes of a size to produce sugar. The trees which have come up since the first clearing, produce sap that yields much more saccharine than the original forest maples.

The whole interior of the northern part of the United States have relied, and still rely, more on their maple woodlands for sugar than on any other source; and as a branch of domestic manufacture and home production, the business is of no little consequence. The time occupied too in the manufacture is very limited, and occurs at a season when very little other labor can be performed.

Hitherto but comparatively little attention has been bestowed upon this important branch of industry in Canada. The inhabitants of that province might doubtless manufacture a sufficient quant.i.ty of maple sugar to supply the demand or consumption in this article for the whole population of the country. This variety of sugar may be refined, and made as valuable for table use as the finest qualities of West India sugar. On the south sh.o.r.e of Lake Huron, and the islands of that inland sea, there are forests of sugar

maple unsurveyed capable of producing a supply for the whole population. The Indians upon those islands have lately turned their attention pretty largely to the manufacture of sugar from the maple; and many tons have been exported from this source. If the Indians could obtain a fair value for their sugar, say seven or eight dollars per 100 lbs., they would extend their operations upon a large scale.

Upon these islands alone, there are upwards of a million of full-grown maple trees, capable of yielding each from two and a half to three pounds of excellent sugar per annum; and if proper attention were given to this branch of production in that quarter, I see no reason why a most profitable business could not be carried on. Every farmer who has a grove of sugar maple, should endeavour to manufacture at least sufficient for the consumption of his own family. In most cases 150 trees of medium growth would yield an amount of sap that would make 300 lbs. of sugar, twenty-five gallons of mola.s.ses, and a barrel of vinegar. The labor required to manufacture this amount of sugar, mola.s.ses, and vinegar, would scarcely be felt by the well-organised cultivator, as the season for the business is at the close of the winter, and opening spring, when no labor can be done upon the land.

In proportion to the amount of labor and money expended in the production of maple sugar, it is as capable of yielding as large a return of profits as any other branch of farm business. It is certainly an object of great national interest to the inhabitants of our North American Colonies, that they should supply their own market with such products as their highly-favored country is capable of producing. Sugar is an article which will ever find a ready sale at highly-remunerating prices, provided that it be properly manufactured and brought into market in good condition. It requires a little outlay at first to purchase buckets, cisterns, and boilers, to stock a sugar bush; but by carefully using the above necessary apparatus, they will last for a very long period. A farmer can supply himself with the suitable materials for performing the sugar business without any cost further than his own labor. The spring is the season of the year that everything should be put in readiness,--even the wood should be chopped and drawn to the spot, so that when the sap commences to run, there may be no impediments in the way to hinder the complete success of the business.

Large tracts of land in the Ottawa district are covered with the true sugar maple. It is found in great numbers in the eastern townships of Lower Canada, where considerable forests of miles in extent contain nothing else, and in other places it is mixed with various trees.

There is scarcely a spot in Lower Canada where it is not to be met with. Capt. Marryatt has stated that there were trees enough on the sh.o.r.es of Lakes Huron and Superior, to supply the whole world with sugar. In the United States, the manufacture of the sugar was first attempted about the year 1752, by some farmers of New England, as a branch of rural economy. This gradually spread wherever the tree was known. Now it forms an article of food throughout a large portion of the country. Almost every farmer prepares sugar enough from the trees in his neighbourhood for the consumption of his family during the year, and has often a surplus for sale. It is much cheaper than muscovado, being sold at from 2d. to 3d. per pound, whilst common muscovado cannot be bought for less than 4d. to 5d. per pound.

The province of Canada produced nearly ten million pounds in 1852, 6,190,694 being made in Lower Canada, and 3,581,505 in Upper Canada.

The quant.i.ty made in Lower Canada in 1849 was only about 1,537,093 lbs. The maple sugar product of the Canadas in 1848 was officially stated as follows:--

lbs.

Upper Canada 4,160,667 Lower Canada 2,303,158 --------- 6,463,835

This product is therefore of immense importance to the British North American provinces, all of which, under a judicious system, might be made to produce vastly increased quant.i.ties of this wholesome and valuable commodity.

The importation of sugar in Canada may very safely be computed at 40,000 per annum, and the whole of this amount of money could be retained in the country if the people would only look well to the matter.

In tapping the tree, the gouge is the best implement that can be used, provided it is an object to save the timber. It is usual, when using the gouge, to take out a chip about an inch and a half in diameter; but this system is objectionable where the maple is not abundant, as it subjects the timber to decay; it is a better course to make an incision by holding the gouge obliquely upwards an inch or more in the wood. A spout, or spile, as it is termed, about a foot long, to conduct off the sap, is inserted about two inches below this incision with the same gouge. By this mode of tapping, the wound in the tree is so small that it will be perfectly healed or grown over in two years.

A boiler, of thick sheet-iron, made to rest on the top of an arch, by which the sides would be free from heat, and only the bottom is exposed, is doubtless a secure and rapid process of evaporation. The sides and ends of the boiler may be made of well-seasoned boards, which will answer the same purpose as if made solely of sheet-iron.

When the sap is boiled down into syrup or thin mola.s.ses, it must be taken out of the boiler and strained through a flannel cloth into a tub, where it should settle about twenty-four hours. The clear syrup should be separated from the sediment, which will be found in the bottom of the tub. The pure syrup must be boiled down into sugar over a slow fire. A short time, however, before the syrup is brought to a boiling heat, to complete the clarifying process, the whites of five eggs well beaten, about one quart of new milk, and a spoonful of saleratus, should be all well mixed with a sufficient amount of syrup, to make 100 lbs. of sugar. The sc.u.m which would rise on the top must be skimmed off. Caution is to be observed in not allowing the syrup to boil until the skimming process is completed. To secure a good article, the greatest attention must be bestowed in granulating the syrup. The boxes or tubs for draining should be large at the top and small at the bottom. The bottom of the tubs should be bored full of small holes, to let the mola.s.ses drain through. After it has nearly done draining, the sugar may be dissolved, and the process of clarifying, granulating, and draining repeated, which will give as pure a quality of sugar as the best refined West India article.

The greatest objections that are advanced against maple sugar are, that the processes made use of in preparing the sugar for market are so rude and imperfect that it is too generally acid, and besides charged with salts of the oxide of iron, insomuch that it ordinarily strikes a black color with tea. These objections may be removed without any comparative difficulty, as it has been proved to demonstration, by the application of one ounce of clear lime-water to a gallon of maple sap, that the acidity will be completely neutralised, and the danger of the syrup adhering to the sides of the boiler totally removed. The acid so peculiar to the maple sugar, when combined with lime in the above proportion, is found to be excessively soluble in alcohol; so much so, that yellow sugar can be rendered white in a few minutes by placing it in an inverted cone, open at the top, with small holes at the bottom, and by pouring on the base of the cone a quant.i.ty of alcohol. This should filtrate through until the sugar is white; it should then be dried and re-dissolved in boiling water, and again evaporated until it becomes dense enough to crystallise. Then pour it into the cones again, and let it harden. By this process a very white sample of sugar may be made, and both the alcohol and acids will be thoroughly dispelled with the vapor.

The process of making maple sugar it will be seen is very simple and easily performed. The trees must be of suitable size, and within a convenient distance of the place where the operations of boiling, &c., are to be performed. When gathered, the sap should be boiled as early as possible, as the quality of the sugar is in a great degree dependent on the newness or freshness of the sap. There is a tendency to acidity in this fluid which produces a quick effect in preventing the making of sugar; and which, when the sap is obliged to be kept for many hours in the reservoirs, must be counteracted by throwing into them a few quarts of slaked lime. During the time of sugar making, warm weather, in which the trees will not discharge their sap, sometimes occurs, and the buckets become white and slimy, from the souring of the little sap they contain. In this case they should be brought to the boiler and washed out carefully with hot water, and a handful of lime to each.

In reducing the sap, the great danger to be apprehended is from burning the liquid after it is made to the consistence of mola.s.ses, since, when this is done, it is impossible to convert it into sugar; a tough, black, sticky ma.s.s, of little value, being the result. Indeed, constant care and attention is required to produce a first-rate article: for though sugar may be made in almost any way where the sap can be procured, yet unless the strictest care is observed in the processes, in gathering and boiling the sap, clarifying the syrup, and in converting the syrup to sugar, a dirty inferior article will be made, instead of the beautiful and delicious sweet which the maple, properly treated, is sure to yield.

The quant.i.ty of sugar produced in a year varies considerably from the same trees. The cause of this difference is to be found in the depth of snow, continued cold, or a sudden transition from cold to warm, thus abridging the period of sugar-making. A sharp frost at night, with clear warm days, is the most favorable to the sugar-maker.

Perhaps four pounds of sugar from a tree may be a pretty fair average of seasons generally, although we have known the growth to exceed six pounds, and sink as low as three. A man will take care of one hundred trees easily, during the season of sugar, which usually lasts from about the middle of March into April, perhaps employing him twenty days in the whole. Dr. Jackson, in his Report of the Maine Geological Survey, gives the following instances of the production of sugar in that State:--

Lbs. of Sugar.

At the Forks of the Kennebec, twelve persons made 3,605 On No. 1, 2d range, one man and a boy made 1,000 In Farmington, Mr. t.i.tcomb made 1,500 In Moscow, thirty families made 10,500 In Bingham, twenty-five families made 9,000 In Concord, thirty families made 11,000