NEWS

VOL. XXI. No. 529.

ON A MINERAL FROM SAN PAOLO.
By Dr. T. L. PHIPSON, F.C.S.,
Member of the Chemical Society of Paris.

A MINERAL from San Paolo, Brazil, was placed in my hands a short time ago in Paris; it was supposed to be a silicate of yttria, and was called Thelline or Thellite. It corresponded in appearance and properties with the silicate of yttria, described by M. Damour, in 1858, as having been found in the diamond sands of Bahia, Brazil; a brown mineral, said to be "probably a silicate of yttria," which whitens before the blowpipe, but does not fuse, and was found to be insoluble in phosphorus-salt.

A small sample of the specimen from San Paolo was confided to me for analysis, with a request that I would make known the result at an early opportunity.

The following is a description of the mineral and its analysis-It is of a light brown colour, translucent on the thin edges, and in the veins which traverse its substance; when pulverised it gives a light yellow powder of great brilliancy, which becomes bright red when heated; it is partially attacked by strong acids. Before the blowpipe it is infusible, but darkens and turns black in the inner flame, and, by continuing the heat for some time, the surface becomes quite white. It scratches glass like a diamond, and cuts it very nearly as easily as the latter, but it will not attack quartz; it gives flashes and sparks of fire when struck smartly in an agate mortar; it is quite devoid of crystallisation, and its fracture is imperfectly conchoidal. No trace of yttria could be obtained from this mineral, but it was found to contain about 1 per cent of glucina as an accidental constituent. It yielded— Silicic acid Water

Peroxide of iron and alumina with)

about 1 per cent of glucina

go'go 4'54

4°56

100'00

The presence of glucina in this mineral, which is evidently a kind of hydrated silica, menilite, or resinite, is rather interesting, and leads me to believe that this earth will be found in other natural kinds of silica. Silicate of glucina (Phenakite) is so closely allied to quartz in appearance and crystalline form that it is easily mistaken for it, and substances possessing, when crystallised, the same crystalline form are often found together in nature. I do not conclude from the above that the mineral I have examined is identical with M. Damour's silicate of yttria, for I am not aware that I have ever seen the latter. Doubtless he will some day publish an analysis of it. Analytical Laboratory, Putney, S.W.

BEET-ROOT SUGAR.

WHEN the Berlin apothecary, Marggraf, in the year 1747, made known, at a meeting of the Royal Prussian Academy of Sciences, the fact that the beet-roct contained sugar identical with that derived from sugar-cane, and that he had obtained, by means of alcohol, 6-2 per cent of sugar from the white variety of beet, and 45 per cent from the red-coloured root, he certainly did not dream that, within a century after his discovery, the manufacture of beet-root sugar would have become one of the most extensive of what is very properly termed, in the German language, landwirthschaftliche Gewerbe, but for which no very

good translation can be given. It is too much the fashion to be chiefly confined to larger centres of population; but this notion is not entertained on the Continent, where, beside beet-root sugar making, the preparation of madder and various derivatives therefrom is conducted in the country, rather than in towns. This is also the case with the distillation of spirits from wine, as well as that obtained from various other sources-viz., potatoes, beetroots, cherries, &c.

The proposals made by M. Marggraf to obtain sugar from beet-roots on the large scale did not then meet with any success, owing to a variety of concurrent causes, among which may be mentioned the cheapness of canesugar, imported into Germany from this country and Holland. About the end of last century, Messrs. Achard and Hermbstädt again called attention to this subject, and succeeded on a sufficiently large scale in obtaining from beet-roots about 6 per cent of crystallised sugar and 4 per cent of molasses. It was, however, mainly due to the political disturbances and wars of the latter end of the last and the first fifteen years of the present century that the manufacture of beet-root sugar was entered into commercially. This was principally due to the encouragement of Napoleon I., aided by the eminent judgment and sound scientific knowledge of one of his ministers-the famous Chaptal. It is true that, almost immediately after Napoleon's fall, the beet-root sugar industry collapsedbut only to be revived on sounder scientific and mercantile principles, its temporary collapse being partly due to the protective tariffs made in favour of colonial sugars; whilst, in some countries, beet-root sugar making was practically prohibited, also, by absurd and injudicious excise regulations.

The plant known as Beta maritima (an unsightly biannual vegetable, which grows wild on the coast of the Mediterranean in Spain, Dalmatia, and some parts of France) is the mother plant from which the sugar-yielding beet has been derived. The well-known red beet is a different variety of the same genus. The beet has been an object of regular cultivation as a suitable cattle-fodder only from the beginning of this century, since which time several varieties have been obtained, partly as a result of cultivation, partly, also, as a consequence of climate and soil. The Beta cicla, or so-called white Silesian beet-root, is considered by many as the best variety for the production of sugar. This root, as well as the other varieties, is a biannual plant. The first year after sowing it only produces rootlets and leaves; in the second year of its growth, the root becomes developed; and, were it not that this vegetable cannot very well stand frost, the best period for its gathering would be in the spring following its second winter. This condition, however, cannot be complied with, and the crop is gathered in the autumn. The weight of the crop of roots gathered from one hectare varies, as might be expected, considerably; but the following figures may give some idea of this subject :-In Austria, from 416 to 580 cwts., yielding from 3080 to 4336 lbs. of sugar; Bohemia, from 448 to 580 cwts., yielding from 3344 to 4640 lbs. of sugar; Prussia, about 720 cwts., yielding about 5344 lbs. of sugar; France, 596 cwts., yielding 4464 lbs. of sugar. The composition of a good kind of the Beta cicla, in 100 parts, is :-Water, 835; sugar, with a trace of dextrine (about o∙1), 10'5; ligneous fibre, o8; albumen, casein, and other albumenoid substances, 15; fatty matter, o1; organic substancesviz., pectine, citric, and pectic acids, a substance which, in contact with air, assumes a rose colour, asparagin, oxalates and pectinates of lime, potassa, and soda; inorganic salts-viz., nitrate and sulphate of potassa, chloride of potassium, phosphate of lime, and magnesia, all together, 37 per cent. It is evident that the juice obtained from a plant of that complex composition is a somewhat difficult fluid to deal with for obtaining sugar therefrom; and, in order fully to illustrate the triumph of well-applied science in this respect, we quote, for compari

son's sake, the percentage composition of sugar-cane:— Sugar, 178; water, 720; cellulose, 9'8; saline matter, o'4. There are various processes in use for obtaining sugar from beet-root; but the following is an outline of the general mode of operating:-The roots are dug up, and the head bearing the leaves (which serve together as fodder) is cut off commonly on the field. The roots are then carted to the sugar works, and there washed by machinery, it being essential that neither clay nor pebbles should remain adhering, since these might injure the machinery by which the roots are next made into pulp, by being torn up by very sharp circular saws, placed close together on a revolving cylinder, making from 1000 to 1200 revolutions per minute. The pulp is placed in bags made of a very strong linen tissue, and from twenty-five to fifty of these bags are placed on each other on the movable plate of a hydraulic press, care being taken to place between every two bags a frame wicker-work or perforated tinned-iron plates. The pressure which can be applied averages from 500 to 700 lbs. per square inch; generally the pressing process is repeated, sometimes with, sometimes without previous moistening of the cake, which, in some cases, is also broken up again. Before we follow the juice obtained by this pressure, we may pay a moment's attention to the cake obtained after it has been submitted to repeated pressure. It exhibits a hard, somewhat plank-like appearance, varying in size with the size of the press-plate, and about § or of an inch thickness. It contains, according to an analysis made at Hohenheim*:-Water, 15.61; ash, 127; cellulose, 1'47; sugar, 1'72; carbohydrates (starch, &c.), 2.84; proteine compounds, o'28; together, 23.2. To which add, to make up the 100 parts of beet-root, 76.8 per cent of juice, containing:Water, 65'95; sugar, 10·17; carbohydrates, 0.63; proteine compounds, o'58. The cake is used as fodder for cattle, or, in some cases, for the manufacture of brandy, vinegar, and, last, but not least, for the manufacture of paper, for which it is increasingly in demand.

The juice, as it runs from the press-plate, is led, by means of gutters, to what is termed a monte-jus, and by its means (by steam) forced up to the defecation-pan, wherein it is rapidly heated, by means of steam (the pan being jacketed), to 85°. This temperature having been reached, a thin milk of lime is added, and the fluid thoroughly stirred up. The lime saturates the free acid present in the juice, and precipitates as well as decomposes the albuminous substances, ammonia being consequently evolved. In order that the lime should act properly, it is necessary to increase the heat, which is raised to near the boiling point of the fluid. The quantity of lime added depends upon the quality of the roots, but is generally about from 1 to 2 lbs. for every 100 litres of juice. The liquor in the defecation-pan is run off clear from the supernatant scum, by means of an ingeniouslycontrived tap, and, previous to reaching the animal-charcoal filters, the fluid is filtered through a peculiar kind of flannel, made on purpose. The defecated juice is not a pure solution of sugar; it contains saccharate of lime, free sugar, free potassa, soda, and some ammonia; small quantities of organic nitrogenous substances, and sulphate and nitrate of potassa. The removal of a portion of these impurities is effected, in many instances, by filtration through animal charcoal, next submitted to the action of a current of carbonic acid, whereby the saccharate of lime is decomposed; and the clear liquid is evaporated to a density of 24° to 25° Beaumé (sp. gr., 1199 to 1210), and again filtered over animal charcoal, in order to remove from the liquid (technically, clearsel) colouring matter and other impurities. The filtered juice should have the colour of pale sherry, and be free from any suspended

This place is situated near Stuttgart, in Wurtemberg, and is one of the largest and the best conducted agricultural colleges in Europe. It is fitted up, not only for theoretical, but also for practical, instruction, and contains a model beet-root sugar work, brewery, distillery, and other manufactories belonging to the class termed, in Germany, Landwirthschaftliche Gewerbe, on a sufficiently large scale for practi

cal use.

CHEMICAL NEWS, Jan. 14, 1870.

This

impurities. The filtered liquor is next evaporated to a density of about 42° Beaumé (sp. gr., 1412). evaporation is best performed in a vacuum-pan. When the proper degree of concentration has been attained, the thickish magma (a mixture of cystallised sugar and syrup or molasses) is run into a copper pan, technically termed a cooler; but this is in so far a misnomer, as the contents of the pan are heated by steam to a higher temperature (above 120°) than was attained in the vacuum-pan. The contents of the pan are kept in constant motion, by means of stirring, while a gang of men are busy carrying the pasty mass to the sugar-loaf forms, in order therein to solidify, and to be deprived of adhering syrup by being washed with a solution of pure sugar, sufficiently concentrated for it not to dissolve any crystallisable sugar, while effectually removing the molasses. Instead of this rather expensive process, which yields refined sugar, it is often omitted, and in its stead is substituted the use of the centrifugal machine, or, also, of the so-called Schutzenbach boxes (iron tanks, with a false bottom made of wire-gauze, upon which the magma, after it has been heated in the coolers, is run), and there left for several days, until the molasses have entirely run off; the produce being raw beet-root sugar, which is not fit for consumption until it has been refined, even if its colour is only pale yellow.

The molasses from beet-root sugar are unfit for use as swetenings, owing to the large quantity of mineral salts they contain. According to Meitzendorf, these molasses consist, in 100 parts, of:—Water, 10:8; mineral salts, 10'5; proteine compounds, 98; sugar (cane-sugar and noncrystallisable sugar), pectin, fatty matter, caramel, and other undetermined organic substances, 68.9. This material is employed for the manufacture of spirits, which, however, are not at all agreeable to the palate, but might be rendered pure by re-distillation with quicklime and the use of freshly-ignited wood-charcoal. The residue of this distillation is a valuable source of potash. In Russia and some parts of Silesia, the molasses are used, along with other fodder, for the cattle-a practice which deserves encouragement.

The Continent of Europe contains 1184 beet-root sugar works situated in Germany, France, Russia (inclusive of Poland), Austria, and Belgium. There are, perhaps, scattered over the rest of Europe, some dozen of these works yet; but their production does not materially add to the 4,475,000 cwts. of beet-root sugar annually produced by the works above named. It is evident that, in countries where labour is cheap, and whose inhabitants, but for the beet-root, would be dependent for their supply of sugar upon countries which possess colonies, or dependencies where sugar-cane can be grown, the cultivation of beetroots intended for the manufacture of sugar is a decided boon. In some cases, objection may be raised to this industry, since it cannot be denied the extensive culture of such crops as, for instance, beet-root, tobacco, madder, &c., may interfere, to some extent, with the cultivation of cereals. Yet, however cogent this objection (which has, also, been several times brought forward against the extensive cultivation of sugar-cane in hot climates), it is an undeniable fact that the rural populations in Europe derive great benefit from this industry, which keeps them suitably employed during the winter months of each year; and the results obtained fully prove that beet-root sugar can hold its ground, and compete successfully with colonial sugar when placed on equality therewith.

As regards the United Kingdom, it cannot but cause some astonishment, that a country ranking first in agriculture, and doubly so in everything relating to manufacturing industry, should have hitherto lagged behind in the successful carrying out of this industry—a fact the more to be wondered at since the cultivation of root crops is very extensively carried on, and the beet-root residues may serve as food for cattle even better than the roots purposely cultivated for that purpose. Agricultural labourers can (as instanced by Continental experience) be readily taught the operations of the beet-sugar manufacture; and the skilled

supervision does not require more than, at the utmost, halfa-dozen men. In France, Belgium, and Germany, women, as well as men, are employed in these works. As to climate, excepting the central and northern parts of Scotland, and the high moor grounds, the United Kingdom is as favourably situated for the cultivation of beet-root for sugar manufacture as any portion of the European Continent; while the higher standard of agricultural efficiency in this country would greatly tend to secure good crops with existing system of rotation. As regards the duty on sugar, this is now equalised with that payable in the neighbouring countries-France, Belgium, and the Netherlands. So that, if this matter were to be properly taken up, and economically carried out, with due foresight, and there were brought to bear upon it that practical scientific knowledge which has raised, on the Continent, this industry from a puny infancy to the full strength of vigorous manhood, there is no doubt that it may become a source of great improvement and well-being to the rural population of this country.

ON THE

MANUFACTURE OF CRUCIBLE STEEL.

By R. H. SMITH, F.C.S., &c.

A GREAT deal is being talked about the production of caststeel directly fron iron ores, or its manufacture from inferior kinds of English iron; but little is known or said (outside the immediate manufacturing districts) as to how the immense quantities of this substance are produced at the present time. The conversion of iron into steel is, perhaps, to be classed among one of the most peculiar, but, at the same time, interesting, processes with which chemists are acquainted.

The ordinary converting furnaces are of a conical shape, the bar-iron laying in stone pots, in contact with charcoal; and the heat to which the iron is exposed is regulated according to the purpose for which it may afterwards be required. The time generally occupied in what is termed "conversion" is about three weeks, a week being taken to raise the heat to a sufficient degree, a second to maintain it at the required temperature, and a third to gradually cool the furnace. When cold, the bars are withdrawn, and found to be covered with blisters, and, if broken, possessing a fracture totally different in appearance to that shown by the iron before treated in the manner described. Several tempers, as they are technically called, are produced in one furnace, and much care is necessary in selecting them out for the different requirements of the melter.

Too much care cannot be taken in the melting of steel, as the after work so much depends upon this part of the process. The melting-holes are on a level with the floor of the furnace-room. Each hole has a flue; and some six, twelve, or more, of these form a flat stack. The grate bars at the bottom of each hole are approached by means of a cellar below. The crucibles, or pots, as they are called, made from a mixture of several kinds of clay and a little cokedust, are formed into shape by means of a plug and flask. The pots are annealed over night, and, when at a dullred heat in the morning, placed in the holes by means of tongs, each furnace taking two pots.

The bar-steel of the required hardness is now broken up, and the crucible charged by means of an iron funnel. The first heat, as it is called, will take from four to five hours before it is ready to be poured; but this greatly depends on the nature and hardness of the steel. The holes are watched and worked by the puller-out; but the word to draw the pot is given by the melter.

The puller-out now lifts the crucible from the hole with large tongs, and places it upon the floor of the furnace. Its contents are then poured by the melter into a mould,

made of cast-iron in two pieces, covered with a coat of coal-tar soot, and held together by rings and wedges.

Great care is required in pouring, or teaming, the steel, as it is technically called, and skill in judging the proper heat when to cast it. Mild or soft steel should be teemed immediately the pot is withdrawn from the furnace; but hard steel may often remain a few minutes with advantage. Each crucible should last one day, and is used three times, with charges of 50, 45, and 40 lbs. respectively. All steel above a chisel temper contains o'90 to 1'00 per cent of carbon. If well melted it will settle down in the mould, leaving a small hole at the top of the ingot. If, however, the molten steel has not remained long enough in the fire, it will pour fiery; and, if the ingot, on cooling, be broken, it will be found to be full of small holes, called honeycombs. Great precaution must also be used in not allowing the metal to remain too long in the fire, as hard steel, when of good quality, will soon scorch, and so render the ingot very brittle.

Well melted steel (say of a tool temper) may be thus known. The ingot will be of a blue colour, with a smooth and even skin; the fracture of uniform brightness, and the outer edge perhaps slightly scorched.

Another very important operation to which steel is subject is the hammering; and probably more good steel is spoiled in this department than any other. The ingot should be well soaked in the flame of the forge-furnace, and not at once (as is often the case) put into a dead firewhere the heat is what is called "dead," and where no flame surrounds the ingot.

The fineness of the fracture of a bar of finished steel greatly depends upon the heat that the bar is allowed to retain when the finishing-stroke of the hammer is upon it. Coarseness and fineness of grain, as judging the temper or quality of cast-steel, is far over-estimated. It is, to a certain extent, an indication of hardness; but so much depends upon the way the bar has been finished, that it is of little practical value. However, best cast-steel, especially when hard, will show a fracture of a silky nature; and, when soft, will look bright, and shine like glass. Common cast-steel, on the other hand, will lack that brightness which is so characteristic of good steel; it will look dull, and have, so to speak, a leaden appearance about it.

In the working of steel, too much care cannot be bestowed; and, where (as in razor-making) the workman is required to use a steel containing about 1.50 per cent of carbon, the durability of the razor will almost entirely depend upon the heat to which he subjects it while forging it into shape.

A useful tool-steel" will contain about 12 to 1.35 per cent of carbon. Spindle-steel, or large-size turning tools, will work well if containing about 115 per cent of carbon. Chisel-steel is a temper much used, will harden at a low heat, and possesses great toughness. Steel of 0.85 to 0.75 per cent of carbon will weld easily, and is adapted for "cold setts," or tools where the principal punishment is on the unhardened part.

In melting, charcoal is largely used when the bar-steel is not of the required hardness. Wolfram and titanium are occasionally used, but with little advantage.

Binoxide of manganese is univerally employed. It forms a good flux, and protects the molten-steel from the action of the air.

Spiegeleisen is much used in Sheffield. It is an alloy of iron with manganese and carbon. The following is an analysis of a good spiegeleisen :Iron (by difference) Manganese Carbon

84.78

IO 21 5'01

100'00

Among the many irons employed in steel-making, none have acquired the reputation that those imported from Sweden have won for themselves, and especially those known as the Dannemora marks.

m

Such brands as Double Bullet (00) and hoop L (L) command a high price, and are much used where the best quality steel is required. Second Swedes, such as Wand Crown, Steinbuck, Great S, K6, &c., are good bodied irons, largely employed, and making a very good steel. Of the commoner marks may be quoted (CW) (SV8) Spider, and FG; and, where a high price cannot be ob tained for the steel, such brands are recommended, being found to melt and work well. English irons and spring ends are also melted, but make an inferior quality of caststeel.

The following is an analysis of tool-steel:

CHEMICAL NEWS, Jan. 14, 1870.

That form of the iron process in which chloride of iron is used does not appear to be suitable for this purpose, on account of the possible loss of chlorine which may take place in the operation; but Bunsen's method of dissolving the ore with hydrochloric acid, passing the liberated chlorine into iodide of potassium solution, and determining the iodine liberated, would probably answer the purpose.

However, there is reason to believe that Sherer and Rumpf have overlooked another circumstance which must be considered in regard to the method of Fresenius and Will. With certain limitations, there is little doubt that this method gives results which are uniform, especially if the manganese ore tested in that way is of German origin, or if it resembles the German ore in being soft and readily soluble; but many varieties of manganese ore now in use are not of that kind. The Spanish, Nova Scotian, and Californian ores, for instance, are often excessively hard, and, even when finely powdered, difficult to dissolve thoroughly. In testing such ores by the method of Fresenius and Will, there is, in the first place, a risk of incomplete solution, which would make the result too low. If heat be applied to the apparatus in order to render solution complete, there is, in the second place, a risk of driving off water, which would make the result too high.

In some instances, the differences that have obtained between the results of tests could not be referred to the presence of iron as metal or protoxide in the ores, inasmuch as Fresenius and Will's method, has, in those cases, been

differences arose from the difficult solubility of the ore. But, however that may be, it seems no longer admissible to use that method for testing manganese ores generally, although there is no reason to doubt the uniformity of its results when applied to the soft kind of ores formerly in use almost exclusively.

The decision then adopted by the Association would seem to have been based more upon differences found, in practice, to exist between working results and the indications of tests made for determining the percentage of manganese binoxide in sample, rather than upon any probable or ascertained cause of variation in the results obtained by the method of Fresenius and Will. It would seem, also, to indicate a desire on the part of manufacturers that tests of manganese ore should express the amount of binoxide available for liberating chlorine, and not the amount actually present in the ores. it is in this respect that the iron method has an advantage over the method of Fresenius and Will, since the presence of iron as metal or protoxide in manganese ore would affect its power of liberating chlorine. The result of a test of such manganese ore by the iron method would be correspondingly affected; but that would not be the case if the method of Fresenius and Will were adopted in the testing.

Much of the discrepancy between the results of tests of manganese ore, and many of the disputes that have arisen as to the percentage of these ores, may, in all probability, have been due to the circumstance mentioned above; and, to provide against a recurrence of such differences, it would seem desirable that, in regard to a certain class of manganese ores, some other mode of testing than that of Fresenius and Will should be agreed upon, so that the valuation of those ores may be based upon the available binoxide, and not upon the actual

amount.

For these reasons, and on account of the long time requisite for dissolving manganese ores of this kind, the method of Fresenius and Will is not well adapted for testing them. For some time past, therefore, I have adopted Mohr's method of using a known quantity of a standard solution of oxalic acid, together with excess of sulphuric acid, for dissolving the ore; if necessary boiling until the ore is completely dissolved, and then, by means of a standard solution of permanganate, determining the quantity of oxalic acid remaining undecomposed. This method is very convenient for testing manganese ores, and since it involves only one weighing for each test, the source of error is less than in the method of Fresenius and Will. The results obtained are also very uniform.

This method has also the advantage of giving results which fairly represent the amount of available binoxide in manganese ores; for any iron that may be present as metal or protoxide would consume an equivalent quantity of permanganate solution, and thus apparently reduce the quantity of oxalic acid decomposed by the binoxide to an extent proportionate to the amount of iron existing in the ore. Thus, for instance, if the quantity of oxalic acid decomposed by 100 grains of manganese ore free from iron or protoxide of iron were 109'53 grains the ore would contain 765 per cent binoxide and the whole of that would be available. But, if the 100 grains of ore also contained 5.6 grains of metallic iron, or an equivalent of protoxide, the permanganate solution required for peroxidising that iron would represent 63 grains of oxalic acid, and the quantity of oxalic acid decomposed by the binoxide would appear so much less than it really was, or 103:23 grains instead of 109.53 grains. Accordingly, the amount of binoxide would be represented as 72.1 per cent, instead of 76.5 per cent; and that would, in fact, be the amount of binoxide available for generating chlorine.

This method of testing recommends itself by its simplicity, and by the fact that the standard solutions of