terms of the compromise act, the duty on the raw sugar underwent biennial reductions, while the drawback was unaltered, the drawback became a direct bounty, and the business was increased as follows':—

1851...

579,627,298 11,220,723 568,406,575

In these figures we have taken no account of maple sugar, because, although that article is a valuable product in the new States, it does not conflict with the cane sugars where the latter are introduced through the operation of the public works, the returns, of which all show an increasing market for the cane sugar, as the districts through which they run become more settled. The prominent fact in the above table is, that while Louisiana aud Cuba afford equal supplies for the consumption of the Union, the former has far outrun Cuba, notwithstanding that the latter has become so much more dependent upon the United States for a market.

The great increase in the import of refined sugar in 1851 was from Belvium and Holland, stimulated by the low price of raw sugars there. Under the operation of the falling duty upon raw sugar, and the unchanged rate of drawback, the export of refined sugars rose from 2,000,000 pounds in 1837, to nearly 14,000,000 pounds in 1841. With the close of that fiscal year, the drawback was reduced from 5 cents to 3 cents, and after January, 1842, to 2 cents. The effect was the instant cessation of the trade, making a difference of near 27,000,000 pounds in the quantity of brown sugar reexported in the shape of refined sugar. This was a very important item, and its effect upon the market was by no means properly estimated.

We

may now take a table of the whole export of sugar from the United States, that is, raw sugar of foreign and domestic origin, and of refined sugar equal to raw, at the rate of two pounds raw for one of refined, as follows:

TOTAL EXPORT OF RAW SUGAR, FOREIGN AND DOMESTIC, AND OF REFINED EQUAL TO RAW,

This table gives the whole annual export demand for raw sugar. The sugar trade of Great Britain in 1849 and 1850 exhibited the following results. The importation of sugar amounted to the quantities here stated:

1840.

1850.

The total quantities of all kinds of sugar and molasses re-exported in the same two years, together with the exports of sugar refined in England,

The gross amount of duty received on the imported sugar was 4,139,9997. in 1849, and 1850, 4,130,819/.

The duties on the importation of sugar into England have varied very considerably. Between the years 1661 and 1815 the duty was gradually raised from 1s. 6d. to 30s. per cwt. on British plantation sugar. From 1815 to 1844 it varied from 24s. to 30s. East India sugar paid a higher duty than West India until 1836, when the two were assimilated. Foreign sugar paid a duty of 60s. to 63s. per cwt. until the recent legislative changes. In 1844 a change was made, whereby sugar from certain foreign countries, under certain defined circumstances, might be admitted at 34s. instead of 63s. duty. In 1845 another act fixed the duty on sugar, from either the East Indies or West Indies, at sums varying from 14s. to 21s., according

to the quality. By an act passed in 1846, there was to be a gradual reduction of duties from 1846 to 1851, at the expiration of which period the duty on foreign sugar was to be the same as that on East or West India sugar. By another act of the British parliament passed in 1848 this principle of gradual reduction is to extend until July, 1854, after which time sugars from all countries will be placed on the same footing. They will pay at that time the following import duties per cwt.:

all

Since preparing the preceding pages on "Sugar and the Sugar Trade," the London Morning Chronicle comes to our hands with the following description of a patent method of sugar manufacture, which has been introduced into Cuba and other sugar producing countries. It increases the quantity of sugar produced besides improving its quality. Patents for the improvement have been secured, as we learn, in the United States.

The new processes are fourfold in their character, comprising, first, a new mode of obtaining the saccharine juice from the cane; secondly, a new mode of defecating and filtering the juice so obtained; thirdly, the boiling and concentrating of the juice; and fourthly, the crystallization and final curing of the sugar. The varied processes are to be seen at a model sugar-house, at the works of Mr. Bessemer, Baxter-house, Old St. Pancras Road, London. By the first improvement, in the construction of the cane-press, a difference in the yield of the cane is obtained, as compared with the old rolling mill, of about 20 per cent. In the new machine, the pressing tubes are reduced in length from 30 inches to 12, the first four of which are parallel, and 3 inches wide-the next four inches of their length being taper, and terminating with a width of but 1 inch, the smaller contracted point extending as far as the exit end of the tube. By this change of form, the entire removal of the elasticity in the "magas" occupying the tubes is removed, and after the cane has been collapsed by the severe pressure, and its breadth at the same time gradually lessened, every fiber and cell is made to assume new relative positions-not one remains unruptured and an increased quantity of the juice is consequently expelled at the trough. In addition to this advantage, there is obviously a more equal distribution of power in each revolution of the machine; the deleterious chlorophyl or coloring matter of the outer portion of the cane is not expelled with the juice, as in the ordinary apparatus; the machine may be more easily fed, and weighs considerably less than rolling machines generally in use.

The juice, when expelled from the cane, is unavoidably mixed with numberless minute fragments of cellular tissue, albumen, and other extraneous matter, which, if not speedily removed, tend to produce the acidification of the liquid. At this stage comes in the second of the processes invented by Mr. Bessemer. The present mode of defecation and filtration consists in raising the temperature of the liquor to 15 degrees Fahrenheit, when a quantity of lime is thrown in for the purpose of neutralizing the free acid, and assisting in the coagulation of the albumen; the temperature is increased to 180 degrees Fahrenheit, when, after allowing time for settling, the scum is removed and the clear liquor drawn off into the "grand" copper, where it is subjected to boiling heat, when the feculent and other albuminous matters are kept constantly removed from its surface. The more completely these impurities are removed, the greater will be the brightness and value of the finished product. In the new process the juice passes through a wire strainer direct from the spout of the mill into the clarifiers, where it is raised to boiling heat by the application of steam, at which temperature it is kept for about three minutes, by which time the whole of its albuminous con

stituents and feculent matter will have been coagulated and chemically separated, but will, of course, still remain mechanically mixed, and, in the form of light flock, pervade the entire bulk of the fluid. These substances are then effectually removed by a process similar to that employed in the manufacture of paper. A drum of about two feet in diameter and from four to five feet in length, is made to revolve slowly in a small semi-circular tray or vessel. This drum is covered with fine wire cloth, through which the water forces its way, leaving a muddy coating of extraneous matters on the other side, which coming in contact as it revolves with a fixed scraper, similar in principle to the "doctor" employed in calico printing, is made to fall off in a state something like dry mud into a receptacle prepared for it. The process is self-acting. It takes in its own supply of foul liquor from an elevated cistern, delivers the clear juice into the evaporating pan, and discharges the refuse as we have already stated.

Up to this stage, the advantages obtained must be evident to all who are acquainted with this interesting branch of manufacture. The liquor being received direct from the press, avoids the necessity of the use of liquor pumps; the clarifiers, not being used as subsiding vessels, are not required to be so large; the loss of juice in the removal of the scum and in the sediment is prevented; the use of the "mont-jus" is rendered unnecessary; the coagulation of the albuminous matter is more rapidly obtained; the evaporating process may follow immediately after the pressing of the canes; and finally, the self-cleansing filter performs its work much better than any continuous process of skimming, and renders unnecessary that watchful attendance which is now so imperatively necessary in order to obtain the required brightness and color of the sugar. The saving of manual labor by those improvements is self-evident.

On the various modes of boiling and concentrating the juice at present in use, whether by a series of semi-globular pans, the vacuum pans, Gadsden's pan, or the apparatus of Mr. Crossley or Mr. Schroder, it is not necessary now to speak; the principle in one and all of them being the same-that of evaporating the fluid from the saccharine matter. The inventor of the process now under consideration, contends that, in all the existing arrangements for the separation of the water from the sugar, boiling under any form, or the use of surfaces or pipes heated by steam, must be totally excluded if the formation of molasses is to be prevented. It is a well established fact that a thermometer placed in a solution heated by steam or the direct action of fire, furnishes no indication of the temperature to which the liquid is exposed, as a vast amount of latent heat is absorbed by fluids in their formation into steam. To the forgetfulness of this simple fact, are to be traced many of the fatal mistakes at present connected with the manufacture of sugar.

Thus, while the temperature of the sirup during ebullition in a vacuum-pan indicates as low perhaps as 180 degress Fahrenheit, the copper worm against which portions of the sugar are constantly brought in contact, is equal to and often above 220 degrees Fahrenheit: the consequence of which is the destruction of the color, and an injury to the crystallizing powers of the sugar. By an arrangement which Mr. Bessemer terms a hot air evaporator, the concentration of saccharine fluids may now, however, be affected without the slightest injury to color or quality, and in an increased quantity.

This apparatus consists of a tank of thin plate iron, of about 10 feet by 8 feet, and 24 feet in depth, which has a false bottom, curved so as to form two parallel segments of a cylinder. Above these and coincident with them is a hollow drum of eighteen inches in diameter, mounted on an axis, and upon which is formed a broad spiral blade in the shape of a screw, or "creeper," the thread of which is about fifteen inches in depth, and the convolutions three-quarters of an inch apart; and between each of the blades or threads of the screw, holes are formed spirally from one end of the drum to the other. At oue end of the hollow drum, air, supplied by a blowing fan, and heated to 150 degress by passing along a flue, is made to enter, which escapes through the holes in the drum in the radial direction, and sweeps like the hot breath of the simoon over the wet surfaces of the various revolving blades, absorbs the moisture thus exposed to its action, and

passes off in an invisible vapor. Upwards of six thousand square feet of evaporating surface is thus obtained in the small space of 10 feet by 8 feet. The screws make about eight revolutions per minute, and as they revolve, the more concentrated portions of the fluid are washed off as they descend into the fluid, and fresh portions are being constantly brought up on the surface of the screw, to be in like manner subjected to the hot-air blast. Finally, after three or four hours, the whole of the surplus liquor is carried off; the remaining fluid is sufficiently concentrated, and assumes a thick gelatinous appearance; and the screw, made to revolve in the opposite direction, expels the solution from the tank ready for the process of crystallization. By this process the sugar is not at any time exposed to a hotter surface than 140 degrees. No boiling, consequently, takes place, no slea is formed, and not one grain of crystallized sugar is converted into molasses. The entire cost of fuel for evaporation is saved, the waste heat of the chimney and waste steam of the engine being alone employed, and the apparatus costs less than the ordinary vapor pans; it can be worked with a small amount of wind or water power. Three hogsheads of sugar, it is stated, can be obtained where two only are now produced, whilst the quality will be superior in color and taste, and will be perfectly free from molasses.

The separation of the crystals from the mother liquor in which they are found, is effected in a most ingenious and efficient manner by the use of the air-pump. The transformation from the most repulsive and unwholesome-looking black sugar into a fine white sugar, is completed in one-seventh of a second by this process. The principle adopted is precisely that employed in "gassing" lace-an operation resorted to for the purpose of removing the minute filaments of cotton adhering to the surface of the fabric. In the case of the crystals of sugar, a thin flim of fluid matter is required to be removed from the surface of the crystal, and this is effected by bringing it into contact with water-a material which would as quickly dissolve the crystal itself, as the flame of the gas would destroy the delicate and fragile web of the bobbin net. How can the water be thus brought into contact with the sugar for such a short period, and in such a manner as only to remove the outer coating of molasses, and leave the crystal uninjured? The process is a very simple one. A table of nine feet in circumference is made to revolve eight times per minute, having a coating of sugar spread over it to the depth of half an inch, and which consequently moves over a space of 72 feet per minute. At one part of the revolution the table is made to pass under a pipe of two inches in diameter, from which a shower of water is falling, and as the pipe is but one-sixth of a foot in diameter, and the table passes it at the rate of 72 feet per minute, it follows that each portion which comes under the falling water will be retained only 1-432 of a minute in each revolution. This table being covered with a thin brass wire gauze, has placed immediately under it a vacuum chamber, into which the falling water, carrying with it the semi-fluid coating of molasses, is drawn as the table revolves, the crystallized sugar remains on the surface pure and white, and is delivered by a scraper into the hogshead placed for its reception.