The juice of the Sorghums is much less pure at best, and varies greatly in the different varieties. In the first place it contains, besides the true cane sugar or sucrose, a variable but very considerable amount of glucose or grape sugar, which is predominant at first, then gradually diminishes as the maturity of the cane is approached, and forms an inevitable source of difficulty in the making of sugar from the juice. In other respects, likewise, (e. g. in the contents of mineral salts) the sorghum juice is not as pure as that of the sugar cane; and as the stem is not nearly as juicy as in the case of the latter, its product per acre, with the ordinary processes, is at best considerably less. But it can be grown where the cane cannot, and geographically is the real competitor of the sugar beet, since both flourish in the same climates and soils, at least in this country. The average sugar percentage found in sorghum, in the East, is about 14.8 per cent.; the average of three California samples, not yet quite mature for sugarmaking, which the writer examined in 1880, was over 14.3 per cent.; the juice contained at the same time, however, an average of 6.5 per cent. of impurities which stand in the way of the granulation of the sugar. This proportion would probably have been materially improved upon by greater maturity of the cane. But it is nevertheless true that when worked on the large scale, the sorghum juice, in consequence of uneven maturity of different stalks and of the several parts of the same stalk, has averaged only about from 10 to 11 per cent. of cane sugar, with some 4 per cent. of other solids. From these causes, sorghum has been until recently regarded as adapted only to the manufacture of syrup or molasses, and it has gained wide acceptance in this capacity in the Eastern States; while the production of sugar from it is as yet in its infancy, with the chances of financial success apparently against it, from causes inherent in the nature of the plant.

As regards the Sugar Beet, its juice is in some respects the least pure of the three. When the ordinary process of sugar-boiling is applied to it, there results a black, tarrylooking mass, whose taste fully justifies its nauseous aspect, and from which little sugar will separate even upon long standing. It certainly required the confidence of a chemist in the resources of his science to take hold of the problem of making white and pure-tasted sugar from such a raw material; and the solution of the problem stands as one of the most striking instances of the utility of apparently recondite research in developing latent resources for industrial

uses.

The juice of the beet (of which from 75 to 80 per cent. can be extracted by hydraulic pressure) ranges in its sugar contents from 6 to as much as 21 per cent.; but the average content of the beets worked in Germany does not exceed 12 to 13 per cent. of cane sugar, the best annual average of one factory having nevertheless ranged as high as 15.6 per cent. The beet juice, however, does not naturally contain any other kind of sugar that would follow the cane sugar into the purified juice, as in the case of sorghum. Besides the sucrose, the beet juice carries only what the manufacturer designates as "non-sugar;" and practically all of this "non-sugar" that is of vegetable origin, can be more or less readily separated out by the treatment of the juice prior to or after the final evaporation. After this purification there remain in it, with the cane sugar, only the greater part of the ash ingredients-mineral salts derived from the soil. The quantity of these is from twice. to as much as five times greater than in the tropical cane juice; but apart from these salts, and a usually smaller percentage of sugar, the purified beet juice stands even with cane juice as regards purity and consequent facility of granulation.

These saline ash ingredients, as stated before, tend to transform the sucrose into

other sugars during the evaporation; their presence is, therefore, very objectionable, and when of a certain kind and in considerable amount, they may render the profitable production of sugar from the juice the juice impossible, by the excessive formation of molasses; a product which as derived from beets is of very little value, being uneatable and, under our present laws, not even capable of profitable transformation into alcohol.

From this unfavorable character of beet molasses there results, also, the propriety of combining the complete purification of the product into "refined sugar" with the working-up of the raw material, with which it forms, practically, one continued process. A beet sugar factory is almost of necessity also a refinery, and turns out only white sugar; while in the case of cane, the juice is first converted into an intermediate product-brown sugar, muscovado, &c.—at the plantations, and is then usually shipped beyond the sea to refineries located in the great commercial centers.

Before discussing the relative commercial prospects of the two prominent sugar crops, it will be proper to give the general reader some insight into the processes through which a beet must pass before acquiring the dignity of white sugar. Most of these may be found illustrated at the Alvarado factory (at this time the only representative of its kind in the United States) and in its neighborhood.

First, as to the root itself, it should be understood that the production of such giants as we are wont to see in the line of common beets and pumpkins, is most emphatically out of place in the case of the sugar-beet. Within reasonable limits, and other things being equal, the smaller the (mature) beet, the higher are, as a rule, its sugar-percentage and purity. Roots above two pounds in weight are usually rejected by the factories, and one and a half pounds is the maximum weight desired; the reason of this will be obvious to any one who will

taste, against each other, the central and the exterior parts of a large beet. The latter will be found very sweet, while the central parts are sometimes almost devoid of sweetness, even to a slight saltiness. Now a small root is "all outside," while its big brother is chiefly "inside." Hence it is obvious that lands whose exuberance cannot be restrained (such as black adobe and rich alluvial soils), are not well adapted to the production of sugar beets, and for obvious reasons saline and "alkali" soils must also be avoided. On the other hand, roots much below three-quarters of a pound in weight, are often fibrous and poorly developed.

Of soil ingredients favorable to the best development of the sugar-making qualities, lime stands foremost and as analysis has shown our soils to be almost throughout rich in that substance, most of the State would on that score be suitable for this culture. But climatic considerations as well as soil quality point especially to the valleys of the coast region, from Mendocino to Los Angeles, as adapted to it; since the excessive heat prevailing in the interior valley in summer would probably prove too much for the preservation of that crispness which is deemed essential in a first-class sugar beet. All the essential conditions of success in its cultivation seem to be combined in a large portion of the " Alameda plains" and other level or sloping lands of the bay region and lower Sacramento, where the lighter sediment soils prevail, and where at present cereal culture, or that of fruit, constitute almost the only alternatives. Between Oakland and San Jose, and in the valley beyond, there is abundant room and excellent opportunity for this addition to diversified agriculture; and with a sufficient number of factories to insure a market, wheat would probably, in this region, soon be abandoned for this sugar crop, so far as the soils permit. The Los Angeles region has already, as above stated, given excellent results as re

gards both quality and quantity of the beet crop, and Ventura and San Luis Obispo can with certainty count on a similar outcome. Parts of Solano, Yolo, and Sacramento Counties, also, will doubtless be successful in sugar beet culture. In fact, the highest sugar percentage until recently known to the writer-19 per cent-has been reported from Sacramento County. As the crispness alluded to as important, is so only with regard to keeping qualities, it may turn out that interior localities having cheap water transportation to the factories, can grow the sugarbeet advantageously for immediate use by the latter. It is intended to test this question practically during the year 1887.

Good beet lands should yield from sixteen to twenty tons of roots per acre; near Alvarado, twenty-four tons has been not an uncommon yield. As the price paid for beets, delivered at the Alvarado factory, has averaged about $4 per ton, the crop is likely to pay quite as well as the average of orchards, and many times better than wheat, so soon as a local market is assured. It is however absolutely essential that the greatest care should be exercised in the selection of seed; this is very commonly undertaken by the factories themselves, they being the parties most deeply interested in the high quality of the crop. It is in fact through the influence of the intelligent self-interest thus brought to bear by the factories, that the sugar-contents of the beet have been raised to so high an average, and in some cases actually to the full percentage of the tropical sugar cane. Moreover, deep and thorough tillage, and clean culture, are necessary conditions of success. The best roots have rather short, spreading tops, of a light green tint, and maturity is indicated by the yellowing and drying-up of the older leaves. The roots are then loosened, but not plowed up, by means of a deep-running subsoil plow run between the rows, after which they are taken up by hand.

The roots are expected to be delivered

with the tops trimmed off, but not otherwise cleaned. It is important that they should be bruised as little as possible. From the dump at the factory they are fed into a hopper from which an apron, or preferably a stream of water, conveys them to the washing tanks. In these they undergo a thorough cleansing by the action of revolving stirrers, which, being invisible beneath the muddy water, impart to the beet multitude a ludicrous appearance of eager and apparently unprovoked activity, from which they presently emerge as "neat as a pin."

In the older practice of the art, still prevailing to some extent, the roots are now delivered into the hoppers of huge revolving graters, to be converted into a soft mush, from which the juice is then extracted either by means of centrifugals or hydraulic presses, or by displacement with water (maceration), or by both methods combined. The press, with its unavoidable incumbrance of costly manual labor, is, however, being more and more replaced by the use of the "diffusion" process, in use at the Alvarado factory, in which the roots, not grated but finely sliced by a machine, are subjected to the action of warm water in large cylindrical closed tanks. called "diffusers," and arranged in a series or circle styled a "battery." In such a battery the water used in extraction passes successively through the entire series of tanks charged with the sliced beets (technically called "cossettes") and becomes warmer and richer in sugar at each passage, until it emerges from the last tank sufficiently rich for boiling. When the cossettes in tank. No. I have become exhausted of all their sugar by the contined passage of fresh water, the contents are discharged through a manhole, and replaced by a fresh charge. No. I now becomes the last in the series, the richest juice being passed into it from the rest of the battery; No. 2 is the next to be exhausted and re-charged in its turn; and so on continuously.

As a matter of course the juice so ob

tained is weaker than would be that obtained by pressing, to the extent of the water used in the diffusion process, say about 15 per cent on an average; but the additional cost thus incurred in the evaporation is amply made up by the more complete extraction of the sugar, and other advantages of too technical a character to be here explained.

Beet cake, whether from pressing or from diffusion, is a very valuable food for cattle, and forms one of the regular sources of income for the factories. In Europe it is not uncommonly exchanged weight for weight, for the fresh roots; at Alvarado it is thus far sold at the low rate of one dollar a ton.

The juice, whether obtained by pressure or diffusion, passes on to the steam-jacketed "defecating" pans or tanks. It reaches these as a usually dark-tinted, unattractive looking and smelling liquid, which on being rapidly heated up to about 180 degrees Fahr., deposits a flocculent mass which is chemically similar to albumen or white-ofegg, and thus on coagulating incloses within its flocks most of the fibrous and fleshy partieles still floating in the liquid; corresponding precisely to the "skimmings" in domestic jelly-making. This alone, however, would not purify the juice sufficiently for the sugar-boiler's purpose; he therefore adds to it, during the heating-up, from two to five per cent of lime, previously slaked. The lime, combining with the acids and most of the gummy and albuminous matters, as well as with some of the sugar of the juice, forms with the former a thick, greenish scum, beneath which the juice appears almost clear and of a yellowish tint, and can be drawn off after a few minutes' rest. The scum and sediment remaining in the pan (from 18 to 30 per cent) is drained of its juice as far as practicable, in flat filtering bags or boxes, in which it is afterwards subjected to hydraulic or other pressure to obtain the remainder. The limy residue constitutes a good fertilizer for the neighboring

beet fields; but at Alvarado is thus far mostly used in road-making.

The clear juice still contains an excess of lime, which would be prejudicial in the succeeding operations. This excess is removed by bubbling through the boiling juice, by means of a pump, air charged with carbonic acid gas, obtained by the combustion of coke or charcoal in a special furnace. The lime separates out in the form of whitish flocks; and if the beets were of good composition and the operations have been carefully managed, the sweet juice ("thin juice ") is now ready for the charcoal filters.

These filters do not serve to remove any remaining turbidity, which should not exist at this stage; but are intended to free the juice from impurities remaining in solution, which resist the lime defecating process, and would seriously impair the quantity and quality of the sugar product. The charcoal used is made from animal bones ("bone-black"), and is prepared for the use of refineries in special establishments, of which several are in active operation in San Francisco. The bone charcoal is used in a state of coarse granulation resembling black blasting powder, and is carefully freed from dust. The granulated bone charcoal is packed into iron cylinders, varying in their dimensions from 12 to over 24 feet in height and from 20 to 38 inches in diameter, which are usually arranged into "batteries" of from three to five cylinders, connected by pipes through which the filtered juice passes automatically, by liquid pressure, from the bottom of one to the top of the next, so as to insure its adequate purification. The charcoal has, however, only a limited power of absorption; it gradually becomes saturated with the impurities of the juice, and can take up no more. It is then washed wirh water to remove the sugar remaining in it, and afterward discharged in order to undergo the "reviving "process; while the cylinder,

charged with fresh charcoal, now takes its place as the last of the battery; precisely as is done in the diffusion process when the sugar of a charge of cossettes has been exhausted.

The "reviving" of the charcoal, for the restoration of its purifying power, is done by successive leaching with weak acid, which dissolves the lime and other mineral substances absorbed; then a process of fermentation, whereby the bulk of the vegetable substances retained by it is destroyed or rendered soluble in water. It is then washed, and finally heated to low redness in closed retorts or cylinders set in a furnace. From these, after cooling, it returns to the filters.

The evaporation of the filtered juice is accomplished in two successive periods. During the first, it is reduced to about onehalf of its original bulk, in a battery of "evaporators;" the juice thus concentrated (" thick juice") is once more passed through the charcoal filters for a final purification; after which it is subjected, in the " vacuum pan," to the final boiling for "masse cuite " or syrup, which on cooling solidifies into crude sugar.

Both evaporations take place in closed vessels in which the best possible vacuum is maintained by means of air pumps, in order that the liquids may boil at as low a temperature as possible; their vapor being condensed by means of a spray of cold water, which with the condensed vapor escapes through a vertical pipe constituting a giant barometer, with overflowing reservoir below. The ingenious arrangements by which the vapor from the evaporators as well as the escape steam from the engine are made to do double and triple duty in aiding the lowtemperature evaporations, are too complex to be more than mentioned here; but it is only fair to state that the refinements of thermic science have been brought into play in this connection, resulting in a material saving in the cost of manufacture, and often

turning the scales as between profit and loss.

According to the method of boiling-down, as controlled by a skilled sugar-boiler, the product is either a very thick syrup, which is left to solidify gradually; or, in the practice most generally prevailing, the "boiled stuff" already comes from the vacuum pan filled with granulated sugar of greater or less fineness, at the option of the boiler. In the older process of refining this brown sugar, it is placed in sieve-bottomed boxes from which the dark-colored syrup drains gradually, and is then followed with a "white syrup" or a solution of pure sugar, which soon displaces the colored one and leaves behind a pure white mass. According to the more modern practice, the cooled "masse cuite" is placed in "centrifuges"— cylinder-shaped sieves-which revolve with great rapidity inside of another cylinder. The holes of the sieves, while retaining the grains of sugar, allow the syrup to pass through in the form of spray, which collects in the outer casing, followed, as in the case of the stationary sieve boxes, by either white syrup or simple water, sprinkled on the inner surface by the operator; or else by steam blown in, which first condenses and so supplies the needful water, but afterwards heats and partially dries the sugar, which is now clean and white; and for transformation into the "granulated" grades of commerce, only requires to be thoroughly dried. This is commonly done in a horizontal, cylindrical drying chamber, within which revolve. little stirring shovels, that at the same time move the drying sugar forward to the farther end. The final phase is seen in a rather noisy "clog dance" executed on revolving platforms by the familiar white barrels, while being filled with the now floury, dry sugar. The knowledge of the fact that this is done for the purpose of closer packing, hardly detracts from the amusing effect of this final jollification, after so many hardships undergone in the sugar's course from the field to the cask.