Sulphate Sentence Examples

This outlet having been closed by small stones and sulphate of lime cement, the pit is filled with sulphur ore, which is heaped up considerably beyond the edge of the pit and covered with a layer of burnt-out ore.

From the heating of native calcium sulphate and carbon is obtained calx sulphurata (U.S. and B.P.), or sulphurated lime, a greyish-white powder.

The whole of the lead and sulphur of the sulphide was found to be present in the sulphate; in other words, the combining ratio of the lead and sulphur was not altered by the addition of the oxygen.

The most common of these sulphides is cobaltous sulphide, CoS, which occurs naturally as syepoorite, and can be artificially prepared by heating cobaltous oxide with sulphur, or by fusing anhydrous cobalt sulphate with barium sulphide and common salt.

In "cold galvanizing" the zinc is deposited electrolytically from a bath, preferably kept neutral or slightly acid, containing a io% solution of crystallized zinc sulphate, ZnSO 4.7H20.

The superiority which is claimed for Burton ales is attributed to the use of well-water impregnated with sulphate of lime derived from the gypseous deposits of the district.

The aqueous solution is turned bluish black by ferrous sulphate containing a ferric salt.

Their produce has gradually decreased since the 17th century, and is now unimportant, but sulphate of copper, iron pyrites, and some gold, silver, sulphur and sulphuric acid, and red ochre are also produced.

Zinc ores, in the several varieties of carbonates, silicates, oxide, sulphide and sulphate of zinc, have been found in several of the Australian states, but have attracted little attention except in New South Wales, where special efforts are being made successfully to produce a high-grade zinc concentrate from the sulphide ores.

The oxide is a black or brown powder according as it is prepared from the exalate or sulphate, and when pure it is non-fluorescent, but mixed with gadolinia or alumina it possesses this property.

Alum and blue vitriol (sulphate of copper) are manufactured from decomposed schists at Khetri in Shaikhawati.

Each cell contains a zinc plate, immersed in a solution of zinc sulphate, and also a porous chamber containing crystals of copper sulphate and a copper plate.

Cadmium sulphate, CdSO 4, is known in several hydrated forms; being deposited, on spontaneous evaporation of a concentrated aqueous solution, in the form of large monosymmetric crystals of composition 3CdSO 4.8H 2 O, whilst a boiling saturated solution, to which concentrated sulphuric acid has been added, deposits crystals of composition CdSO 4 4H 2 0.

Chemicals sulphate of copper, employed chiefly as a preventive 01 certain maladies of the vine; carbonate of lead, hyper.

Any poisonous substance that is not included in the schedules can be sold by anyone, as, for instance, red lead, sulphate of copper, &c. The duty of the Pharmaceutical Society is a purely legal one, and relates only to the schedules of poisons framed by the government to protect the public by rendering it a difficult matter to obtain the poisons most frequently used for criminal purposes.

The treatment is therefore to administer an ounce of sodium sulphate in water by the mouth, or to inject a similar quantity of the salt in solution directly into a vein or into the subcutaneous tissues.

Magnesium sulphate may be given by the mouth, but is poisonous if injected intravenously.

In this latter reaction the deep yellow solution obtained is exposed to air when the calcium polysulphide formed is gradually converted into thiosulphate by oxidation, and the calcium salt thus formed is converted into the sodium salt by sodium carbonate or sulphate.

The dithionates are all soluble in water and when boiled with hydrochloric acid decompose with evolution of sulphur dioxide and formation of a sulphate.

After unsuccessful attempts to rid themselves of the mice, the farmers appealed to the United States Biological Survey, and alfalfa hay poisoned with strychnia sulphate was used successfully in the Humboldt Valley in January 1908 and in the Carson Valley, where a similar plague threatened, in April 1908.5 Minerals.

For example, when metallic zinc is dissolved in dilute sulphuric acid with production of zinc sulphate (in solution) and hydrogen gas, a definite quantity of heat is produced for a given amount of zinc dissolved, provided that the excess of energy in the initial system appears entirely as heat.

It was about this time that the value of a mixture of lime and sulphate of copper (bouillie bordelaise), sprayed in solution upon the growing plants, came to be recognized as a check upon the ravages of potato disease.

Successful trials of sulphate of copper solution as a means of destroying charlock in corn crops took place in the years 1898-1900.

Artificially prepared crystals of barytes may be obtained by allowing a solution of a soluble barium salt to diffuse slowly into a solution of a soluble sulphate.

Its property of absorbing large proportions of water, up to 80%, and yet present the appearance of a hard solid body, makes the material a basis for the hydrated soaps, smooth and marbled, in which water, sulphate of soda, and other alkaline solutions, soluble silicates, fuller's earth, starch, &c. play an important and bulky part.

The ores found here comprise silver-free galena, sulphate of zinc and calamine.

The dioxide, Ru02, is formed by heating sulphate, or by heating the metal in a current of oxygen.

The insoluble residue contains a mixture of two sulphides, one of which is converted into the sulphate by nitric acid, whilst the other (a crystalline solid) is insoluble in acids.

Ruthenium sulphate, Ru(S04)2, as obtained by oxidizing the sulphide, is an orange-yellow mass which is deliquescent and dissolves in water, the solution possessing a strongly acid reaction.

Thus copper sulphate was CuO+S0 3, potassium sulphate 2S0 3 +P00 2 (the symbol Po for potassium was subsequently discarded in favour of K from kalium).

For example, positive iron combined with negative oxygen to form positive ferrous oxide; positive sulphur combined with negative oxygen to form negative sulphuric acid; positive ferrous oxide combined with negative sulphuric acid to form neutral ferrous sulphate.

The compounds of mercury attracted considerable attention, mainly on account of their medicinal properties; mercuric oxide and corrosive sublimate were known to pseudo-Geber, and the nitrate and basic sulphate to " Basil Valentine."

Sulphur dioxide, recognized by its smell and acid reaction, results from the ignition of certain sulphites, sulphates, or a mixture of a sulphate with a sulphide.

Any residue consists of black mercuric sulphide (and possibly white lead sulphate), in which mercury is confirmed by its usual tests.

The carbonates are dissolved in hydrochloric acid, and calcium sulphate solution is added to a portion of the solution.

The solution free from barium is treated with ammonia and ammonium sulphate, which precipitates strontium, and the calcium in the solution may be identified by the white precipitate with ammonium oxalate.

The substance is heated with metallic sodium or potassium (in excess if sulphur be present) to redness, the residue treated with water, filtered, and ferrous sulphate, ferric chloride and hydrochloric acid added.

Examples of the first case are found among the colourless acridines and quinoxalines which give coloured salts; of the second case we may notice the colourless hydrochloride and sulphate of the deep yellow o-aminobenzophenone.

For example, episomorphs of white potash alum and violet chrome alum, of white magnesium sulphate and green nickel sulphate, and of many other pairs of salts, have been obtained.

Magnesium sulphate (orthorhombic) takes up ferrous sulphate (monoclinic) to the extent of 19%, forming isomorphous orthorhombic crystals; ferrous sulphate, on the other hand, takes up magnesium sulphate to the extent of 54% to form monoclinic crystals.

It is remarkable that even a small addition of zinc-white (oxide of zinc) to the reddish varieties especially causes a considerable diminution in the intensity of the colour, while dilution with artificial precipitated sulphate of lime ("annalin") or sulphate of baryta ("blanc fix") acts pretty much as one would expect.

Among the analytical methods worked up by him the best known is that for the estimation of sugars by "Fehling's solution," which consists of a solution of cupric sulphate mixed with alkali and potassium-sodium tartrate (Rochelle salt).

In a purer condition it may be obtained by the action of sulphuric acid on a mixture of potassium nitrate and ferrous sulphate, or of hydrochloric acid on a mixture of potassium nitrate and ferric chloride.

It may be recognized by the blue colour it gives with diphenylamine sulphate and by its reaction with potassium iodide-starch paper.

Lime is transported in solution as sulphate and bicarbonate, both of which salts are soluble to some extent in water.

All these animals have calcareous skeletons or shells of some form and they secrete the calcium from its solution as sulphate, converting it into carbonate.

As an example we may take the case of a solution of a salt such as copper sulphate in water, through which an electric current is passed between copper plates.

Constant cells may be divided into two groups, according as their action is chemical (as in the bichromate cell, where the hydrogen is converted into water by an oxidizing agent placed in a porous pot round the carbon plate) or electrochemical (as in Daniell's cell, where a copper plate is surrounded by a solution of copper sulphate, and the hydrogen, instead of being liberated, replaces copper, which is deposited on the plate from the solution).

As an example of a fairly constant cell we may take that of Daniell, which consists of the electrical arrangement - zinc zinc sulphate solution copper sulphate solution copper, - the two solutions being usually separated by a pot of porous earthenware.

Thus as long as a moderate current flows, the only variation in the cell is the appearance of zinc sulphate in the liquid on the copper side of the porous wall.

The concentration of the simple copper ions is then so much diminished that the copper plate becomes an anode with regard to zinc. Thus the cell - copper I potassium cyanide solution I potassium sulphate solution - zinc sulphate solution I zinc - gives a current which carries copper into solution and deposits zinc. In a similar way silver could be made to act as anode with respect to cadmium.

If a glucose solution be added to copper sulphate and much alkali added, a yellowish-red precipitate of cuprous hydrate separates, slowly in the cold, but immediately when the liquid is heated; this precipitate rapidly turns red owing to the formation of cuprous oxide.

Barreswil found that a strongly alkaline solution of copper sulphate and potassium sodium tartrate (Rochelle salt) remained unchanged on boiling, but yielded an immediate precipitate of red cuprous oxide when a solution of glucose was added.

The acid employed may be hydrochloric, which gives the best results, or sulphuric, which is used in Germany; sulphuric acid is more readily separated from the product than hydrochloric, since the addition of powdered chalk precipitates it as calcium sulphate, which may be removed by a filter press.

Most of the rubber now manufactured is not combined with sulphur when in the form of sheets, but is mechanically incorporated with about one-tenth of its weight of that substance by means of the mixing rollers - any required pigment or other matter, such as whiting or barium sulphate, being added.

Zinc is commonly deposited by electrolysis on iron or steel goods which would ordinarily be "galvanized," but which for any reason may not conveniently be treated by the method of immersion in fused zinc. The zinc cyanide bath may be used for small objects, but for heavy goods the sulphate bath is employed.

Anglesite, or lead sulphate, PbSO 4, is poor in silver, and is only exceptionally mined by itself; it occurs in quantity in France, Spain, Sardinia and Australia.

Of other lead minerals we may mention the basic sulphate lanarkite, PbO PbSO 4; leadhillite, PbSO 4.3PbCO 3; the basic chlorides matlockite, PbO PbC12j and mendipite, PbC1 2.2PbO; the chloro-phosphate pyromorphite, PbC12.3Pb3(P04)2, the chloro-arsenate mimetesite, PbC12.3Pb3(As04)2; the molybdate wulfenite, PbMoO 4; the chromate crocoite or crocoisite, PbCrO 4; the tungstate stolzite, PbW04.

The first effect of the roasting is the elimination of sulphur as sulphurdioxide, with formation of oxide and sulphate of lead.

In practice this oxidation process is continued until the whole of the oxygen is as nearly as possible equal in weight to the sulphur present as sulphide or as sulphate, i.e.

At this stage as a rule some rich slags of a former operation are added and a quantity of quicklime is incorporated, the chief object of which is to diminish the fluidity of the mass in the next stage, which consists in this, that, with closed air-holes, the heat is raised so as to cause the oxide and sulphate on the one hand and the sulphide on the other to reduce each other to metal.

Thus, a mixture of lead sulphate (45%) and oxide (44%) with some sulphide (8%), zinc and carbonaceous matter, is agglomerated by a heap-roast and then smelted in a slag-eye furnace with grey slag from the ore-hearth.

This is drawn off, cooled and filtered, and forms a white paint of good body, consisting of about 65% lead sulphate, 26% lead oxide, 6% zinc oxide and 3% other substances.

In small works the cupellation is finished in one furnace, and the resulting low-grade silver fined in a plumbago crucible, either by overheating in the presence of air, or by the addition of silver sulphate to the melted silver, when air or sulphur trioxide and oxygen oxidize the impurities.

The word "pure" is emphasized because experience shows that the presence in a water of even small proportions of calcium bicarbonate or sulphate prevents its action on lead.

Boiling concentrated sulphuric acid converts lead into sulphate, with evolution of sulphur dioxide.

It is also obtained by passing chlorine into a suspension of lead oxide or carbonate, or of magnesia and lead sulphate, in water; or by treating the sesquioxide or red oxide with nitric acid.

Venetian white, Hamburg white and Dutch white are mixtures of one part of white lead with one, two and three parts of barium sulphate respectively.

It dissolves in strong nitric acid with the formation of the nitrate and sulphate, and also in hot concentrated hydrochloric acid.

Lead sulphate, PbSO 4, occurs in nature as the mineral anglesite (q.v.), and may be prepared by the addition of sulphuric acid to solutions of lead salts, as a white precipitate almost insoluble in water (1 in 21,739), less soluble still in dilute sulphuric acid (1 in 36,504) and insoluble in alcohol.

Ammonium sulphide blackens it, and it is soluble in solution of ammonium acetate, which distinguishes it from barium sulphate.

Strong sulphuric acid dissolves it, forming an acid salt, Pb(HS04)2, which is hydrolysed by adding water, the normal sulphate being precipitated; hence the milkiness exhibited by samples of oil of vitriol on dilution.

The treatment is the prompt use of emetics, or the stomach should be washed out, and large doses of sodium or magnesium sulphate given in order to form an insoluble sulphate.

This property seems to characterize a solution of iron sulphate in water; a solution of ordinary (potash) alum would possess no such property.

Possibly in certain places the iron sulphate may have been nearly wanting, and then the salt would be white, and would answer, as Pliny says it did, for dyeing bright colours.

It was most commonly an iron sulphate, sometimes probably an aluminium sulphate, and usually a mixture of the two.

In the writings of the alchemists we find the words misy, sory, chalcanthum applied to alum as well as to iron sulphate; and the name atramentum sutorium, which ought to belong, one would suppose, exclusively to green vitriol, applied indifferently to both.

In the roasting process, sulphuric acid is formed and acts on the clay to form aluminium sulphate, a similar condition of affairs being produced during weathering.

The mass is now systematically extracted with water, and a solution of aluminium sulphate of specific gravity 1.16 is prepared.

This solution is allowed to stand for some time (in order that any calcium sulphate and basic ferric sulphate may separate), and is then evaporated until ferrous sulphate crystallizes on cooling; it is then drawn off and evaporated until it attains a specific gravity of 1.40.

It is now allowed to stand for some time, decanted from any sediment, and finally mixed with the calculated quantity of potassium sulphate (or if ammonium alum is required, with ammonium sulphate), well agitated, and the alum is thrown down as a finely-divided precipitate of alum meal.

If much iron should be present in the shale then it is preferable to use potassium chloride in place of potassium sulphate.

In the preparation of alum from clays or from bauxite, the material is gently calcined, then mixed with sulphuric acid and heated gradually to boiling; it is allowed to stand for some time, the clear solution drawn off and mixed with acid potassium sulphate and allowed to crystallize.

The precipitate is then dissolved in sulphuric acid, the requisite amount of potassium sulphate added and the solution allowed to crystallize.

Columbium compounds are usually prepared by fusing columbite with an excess of acid potassium sulphate, boiling out the fused mass with much water, and removing tin and tungsten from the residue by digestion with ammonium sulphide, any iron present being simultaneously converted into ferrous sulphide.

It burns readily in air, and is converted into the pentoxide when fused with acid potassium sulphate.

Cold mineral springs are at Bartfa, with alkaline ferruginous waters; Czigelka, with iodate waters; Parad, with ferruginous and sulphate springs; Koritnicza or Korytnica, with strong iron springs; and the mineral springs of Budapest.

Berzelius about 1823 found that the yellow oxide, when treated with excess of sulphuric acid, gave a sulphate not unlike the ferric salt.

The sulphates are treated with water, which dissolves the uranium and other soluble salts, while silica, lead sulphate, &c., remain; these are removed by filtration.

The solutions are oxidized, precipitated with ammonia, the precipitate dissolved in hydrochloric acid, and re-thrown down by boiling with sodium sulphate.

It appears that with soils which are not rich in humus or not deficient in lime, calcium cyanamide is almost as good, nitrogen for nitrogen, as ammonium sulphate or sodium nitrate; but it is of doubtful value with peaty soils or soils containing little lime, nor is it usefully available as a top-dressing or for storing.

The essential materials of which these mixtures are made are, for English flint glass, sand, carbonate of potash and red lead; for plate and sheet glass, sand, carbonate or sulphate of soda.

A certain proportion of soda ash (carbonate of soda) is also used in some works in sheet-glass mixtures, while " decolorizers " (substances intended to remove or reduce the colour of the glass) are also sometimes added, those most generally used being manganese dioxide and arsenic. Another essential ingredient of all glass mixtures containing sulphate of soda is some form of carbon, which is added either as coke, charcoal or anthracite coal; the carbon so introduced aids the reducing substances contained in the atmosphere of the furnace in bringing about the reduction of the sulphate of soda to a condition in which it combines more readily with the silicic acid of the sand.

For the highest quality of bottles, which are practically colourless, sand, limestone and sulphate and carbonate of soda are used.

For the commoner grades of dark-coloured bottles the glass mixture is cheapened by substituting common salt for part of the sulphate of soda, and by the addition of felspar, granite, granulite, furnace slag and other substances fusible at a high temperature.

The materials employed are sand, sulphate of soda, nitrate of soda, calcspar and in some works carbonate of barium.

It decomposes solutions of silver nitrate and copper sulphate.

In the case of iron, ferric sulphate, Fe2(S04) 3, is produced; tin yields a somewhat indefinite sulphate of its oxide Sn02.

This disease has been successfully treated with a spray of copper sulphate and lime, or sulphate of iron; solutions of these salts prevent the conidia from germinating.

As a preventive to its attacks the copper sulphate sprays and a solution (50%) of iron sulphate have been found very useful, as well as care in planting on well-drained soil that does not lie too low, the disease seldom appearing in dry, well-exposed vineyards.

The iron sulphate solution should be used while the vines are in a dormant condition, and diseased parts should be cleared away and burned, The black rot, like the Uncinula and Plasmopara, is also American in its origin.

After the sweets have come away, cold water is passed through the char until no trace of lime or sulphate of lime is found in it; then a large manhole at the bottom of the cistern is opened, and the washed and spent char is removed.

Pomegranate root, or, better, the sulphate of pelletierine in dose of 5 grains with an equal quantity of tannic acid, may be used to replace the male fern.

It is only when these conditions are attended to that decay and nitrification of dung, guano, fish-meal, sulphate of ammonia and other manures take place, and the constituents which they contain become available to the crops for whose benefit they have been applied to the land.

If the zinc is present as blende, this operation offers considerable difficulties, because in the roasting process the zinc sulphide passes in the first instance into sulphate, which demands a high temperature for its conversion into oxide.

Nahnsen's process, with an electrolyte containing alkali-metal sulphate and zinc sulphate, has been used in Germany, and a process invented by Dieffenbach has also been tried in that country.

A rod of perfectly pure zinc, when immersed in dilute sulphuric acid, is so very slowly attacked that there is no visible evolution of gas; but, if a piece of platinum, copper or other more electro-positive metal be brought into contact with the zinc, it dissolves readily, with evolution of hydrogen and formation of the sulphate.

Zinc sulphate, ZnS04+7H20, or white vitriol, is prepared by dissolving the metal in dilute sulphuric acid.

Zinc sulphate, like magnesium sulphate, unites with the sulphates of the potassium metals and of ammonium into crystalline double salts, ZnS04 R2S04-+-6H20, isomorphous with one another and the magnesium salts.

Zinc carbonate, ZnCO 3, occurs in nature as the mineral calamine (q.v.), but has never been prepared artificially, basic carbonates, ZnCO 3 .xZn(OH) 2, where x is variable, being obtained by precipitating a solution of the sulphate or chloride with sodium carbonate.

In the case of acetate the precipitation is quite complete; from a sulphate or chloride solution the greater part of the metal goes into the precipitate; in the presence of a sufficiency of free HC1 the metal remains dissolved; sulphide of ammonium precipitates the metal completely, even in the presence of ammonium salts and free ammonia.

Those treated here are the sulphate, oxide, carbonate, oleate and acetate.

Lotio Rubra, the familiar "Red Lotion," a solution of zinc sulphate, is widely used in many catarrhal inflammations, as of the ear, urethra, conjunctiva, &c. There are also innumerable ointments.

The sulphate is an excellent emetic in cases of poisoning, acting rapidly and without much nausea or depression.

It is a monacid base; the hydrochloride, C 20 H 17 N0 4 HC1, is insoluble in cold alcohol, ether and chloroform, and soluble in 500 parts of water; the acid sulphate, C 20 H 17 N0 4 H 2 SO 4, dissolves in about loo parts of water.

It gives the normal sulphate as a yellow, deliquescent, amorphous mass when treated with nitric acid.

Strontium sulphate, SrSO 4, found in the mineral kingdom as celestine, is formed when sulphuric acid or a soluble sulphate is added to a solution of a strontium salt.

Strontium salts may be recognized by the characteristic crimson colour they impart to the flame of the Bunsen burner and by the precipitation of the insoluble sulphate.

Evidently the idea of the great Yokoya experts, the originators of the style, was to break away from the somewhat formal monotony of ordinary engraving, where each line performs exactly the same function, and to convert the chisel into an artists i It is first boiled in a lye obtained by lixiviating wood ashes; it is next polished with charcoal powder; then immersed in plum vinegar and salt; then washed with weak lye and placed in a, tub of water to remove all traces of alkali, the final step being to digest in a boiling solution of copper sulphate, verdigris and water.

In Berzelius' system + potassium sulphate is to be regarded as K 2 0.S0 3; electrolysis should simply effect the disruption of the positive and negative components, potash passing with the current, and sulphuric acid against the current.

Potassium permanganate in acid solution oxidizes it to carbon dioxide and water; the manganese sulphate formed has a catalytic accelerating effect on the decomposition.

Thus a strip of zinc plunged into a solution of silver sulphate, containing not more than 0.03 gramme of silver in the litre, becomes covered with a flocculent precipitate which is a true alloy of silver and zinc, and in the same way, when copper is precipitated from its sulphate by zinc, the alloy formed is brass.

This water cannot be entirely removed by fractional distillation, and to prepare anhydrous or "absolute" alcohol the commercial product must be allowed to stand over some dehydrating agent, such as caustic lime, baryta, anhydrous copper sulphate, &c., and then distilled.

The specific gravity of gold obtained by precipitation from solution by ferrous sulphate is from 19.55 to 20.72.

The Japanese use for ornament an alloy of gold and silver, the standard of which varies from 350 to 500, the colour of the precious metal being developed by " pickling " in a mixture of plum-juice, vinegar and copper sulphate.

Subsequent treatment with sulphuric acid renders the copper soluble in water as sulphate, and the final residue contains only gold and silver, which is parted or refined in the ordinary way.

This method of separating gold from copper, by converting the latter into oxide and sulphate, is also used at Oker in the Harz.

In the case of ferrous sulphate, prepared by dissolving iron in dilute sulphuric acid, the reaction follows the equation AuCl 3 +3FeS04 = FeC13-I-Fe2(S04)3+Au.

It is based upon the facts that concentrated hot sulphuric acid converts silver and copper into soluble sulphates without attacking the gold, the silver sulphate being subsequently reduced to the metallic state by copper plates with the formation of copper sulphate.

Generally the reaction mixture is allowed to cool, and the residue, which settles to the bottom of the pot, consists of gold together with copper, lead and iron sulphates, which are insoluble in strong sulphuric acid; silver sulphate may also separate if present in sufficient quantity and the solution be sufficiently cooled.

Fusion with an alkaline bisulphate converts the silver into the sulphate, which may be extracted by boiling with sulphuric acid and then with water.

Another process consists in treating a mixture of the residue with one-quarter of its weight of calcined sodium sulphate with sulphuric acid, the residue being finally boiled with a large quantity of acid.

The solution may be directly precipitated with copper, the copper passing into solution as copper sulphate, and the silver separating as a mud, termed " cement silvers" Or the silver sulphate may be separated from the solution by cooling and dilution, and then mixed with iron clippings, the interaction being accompanied with a considerable evolution of heat.

Or Gutzkow's method of precipitating the metal with ferrous sulphate may be employed.

A certain amount of bismuth sulphate is always formed during the calcination; this is subsequently reduced to the sulphide and ultimately to the metal in the fusion.

Bismuth sulphate, B12(S04)3, is obtained as a white powder by dissolving the metal or sulphide in concentrated sulphuric acid.

There must be considerable dissociation of molecules, and as a first approximation it may be taken that of io molecules of most of the components about 9 (or in the case of magnesium sulphate 5) have been separated into their ions, and that it is only during slow concentration as in a natural saline that the ions combine to produce the various salts in the proportions set out in the above table.

Magnesium sulphate amounts to 4.7% of the total salts of sea-water according to Dittmar, but to 23.6% of the salts of the Caspian according to Lebedinzeff; in the ocean magnesium chloride amounts to 10.9% of the total salts, in the Caspian only to 4.5%; on the other hand calcium sulphate in the ocean amounts to 3.6%, in the Caspian to 6.9 This disparity makes it extremely difficult to view ocean water as merely a watery extract of the salts existing in the rocks of the land.

For this purpose the zero or pure blue is represented by a solution of i part of copper sulphate and 9 parts of ammonia in 190 parts of water.

The composition of the ash of true coal approximates to that of a fire-clay, allowance being made for lime, which may be present either as carbonate or sulphate, and for sulphuric acid.

Caesium hydroxide, Cs(OH) 2, obtained by the decomposition of the sulphate with baryta water,is a greyish-white deliquescent solid,which melts at a red heat and absorbs carbon dioxide rapidly.

Caesium sulphate, Cs 2 SO 4, may be prepared by dissolving the hydroxide or carbonate in sulphuric acid.

The sulphate, Sm 2 (SO 4) 3.81120, is obtained by the action of sulphuric acid on the nitrate.

Chemical methods of sterilization have also been suggested, depending on the use of iodine, chlorine, bromine, ozone, potassium permanganate, copper sulphate or chloride and ()their substances.

After fusion, the mass is finely powdered and treated with cold dilute hydrochloric acid; and when action has finished, nitric and sulphuric acids are added, the precipitated barium sulphate removed, the liquid distilled and the osmium precipitated as sulphide.

The double fluoride is decomposed with hot concentrated sulphuric acid; the mixed sulphate is dissolved in water; and the zirconia is precipitated with ammonia in the cold.

The anhydrous oxide is with difficulty soluble even in hydrofluoric acid; but a mixture of two parts of concentrated sulphuric acid and one of water dissolves it on continued heating as the sulphate, Zr(S04)2.

The sulphate, Zr(S04)2, is a white mass obtained by dissolving the oxide or hydroxide in sulphuric acid, evaporating and heating the mass to nearly a red heat.

Marcasite readily oxidizes on exposure to moist air, with the production of sulphuric acid and a white fibrous efflorescence of ferrous sulphate, and in course of time specimens in collections often became completely disintegrated.

It is abundant, for example, in the plastic clay of the Brown Coal formation at Littmitz, near Carlsbad, in Bohemia, at which place it has been extensively mined for the manufacture of sulphur and ferrous sulphate.

In combination with calcium sulphate, it constitutes the mineral glauberite or brongniartite, Na2S04 CaS041 which assumes forms belonging to the monoclinic system and occurs in Spain and Austria.

The Edison electric meter, like those of Sprague and Lane-Fox, was based upon the principle that when an electric current flows through an electrolyte, such as sulphate of copper or sulphate of zinc, the electrodes being plates of copper or zinc, metal is dissolved off one plate (the anode) and deposited on the other plate (the cathode).

It consisted of a glass vessel, containing a solution of sulphate of zinc, in which were placed two plates of pure amalgamated zinc. These plates were connected by means of a german-silver shunt, their size and the distance between them being so adjusted that about ii 0 - 0 - part of the current passing through the meter travelled through the electrolytic cell and -j o i j of the current passed through the shunt.

The shunted voltameter was then inserted in series with the electric supply mains leading to the house or building taking electric energy, and the current which passed dissolved the zinc from one plate and deposited it upon the other, so that after a certain interval of time had elapsed the altered weight of the plates enabled the quantity of electricity to be determined from the known fact that an electric current of one ampere, flowing for one hour, removes 1.2533 grammes of zinc from a solution of sulphate of zinc. Hence the quantity in amperehours passing through the electrolytic cell being known and the fraction of the whole quantity taken by the cell being known, the quantity supplied to the house was determined.

In the Long-Schattner electrolytic meter a solution of sulphate of copper is electrolyzed.

In the Long-Schattner electrolytic meter, the insertion of the coin depresses a copper plate or plates into an electrolytic cell containing a solution of sulphate of copper; the passage of the current dissolves the copper off one of the plates, the loss in weight being determined by the quantity of the electricity passed.

Thus the sulphate constitutes the minerals anhydrite, alabaster, gypsum, and selenite; the carbonate occurs dissolved in most natural waters and as the minerals chalk, marble, calcite, aragonite; also in the double carbonates such as dolomite, bromlite, barytocalcite; the fluoride as fluorspar; the fluophosphate constitutes the mineral apatite; while all the more important mineral silicates contain a proportion of this element.

The artificial manure known as "superphosphate of lime" consists of this salt and calcium sulphate, and is obtained by treating ground bones, coprolites, &c., with sulphuric acid.

Calcium monosulphide, CaS, a white amorphous powder, sparingly soluble in water, is formed by heating the sulphate with charcoal, or by heating lime in a current of sulphuretted hydrogen.

Sulphuric acid gives a white precipitate of calcium sulphate with strong solutions; ammonium oxalate gives calcium oxalate, practically insoluble in water and dilute acetic acid, but readily soluble in nitric or hydrochloric acid.

Ammonia is found in small quantities as the carbonate in the atmosphere, being produced from the putrefaction of nitrogenous animal and vegetable matter; ammonium salts are also found in small quantities in rain-water, whilst ammonium chloride (sal-ammoniac) and ammonium sulphate are found in volcanic districts; and crystals of ammonium bicarbonate have been found in Patagonian guano.

The commercial salt is known as salvolatile or salt of hartshorn and was formerly obtained by the dry distillation of nitrogenous organic matter such as hair, horn, decomposed urine, &c., but is now obtained by heating a mixture of sal-ammoniac, or ammonium sulphate and chalk, to redness in iron retorts, the vapours being condensed in leaden receivers.

Ammonium nitrate, NH 4 NO 3, is prepared by neutralizing nitric acid with ammonia, or ammonium carbonate, or by double decomposition between potassium nitrate and ammonium sulphate.

Ammonium nitrite, NH 4 NO 2, is formed by oxidizing ammonia with ozone or hydrogen peroxide; by precipitating barium or lead nitrites with ammonium sulphate, or silver nitrite with ammonium chloride.

The aqueous solution on boiling loses some ammonia and forms an acid sulphate.

In this attempt he was unsuccessful, but the observations he made in the course of his experiments induced him, early in 1856, to try the effect of treating aniline sulphate with bichromate of potash.

The solid crusts found at the bottom of the salt lakes of the Araxes plain in Armenia contain about 16% of carbonate and 80 of sulphate.

In Wyoming, California and Nevada enormous deposits of carbonates, mixed in some cases with sulphate and with chloride, occur.

Hydrated sulphates occur at several localities in the province of Madrid and in other provinces of Spain, and at Miihlingen in Aargau, and copious deposits of glauberite, the double sulphate of sodium and calcium, are met with in the salt-mines of Villarrubia in Spain, at Stassfurt, and in the province of Tarapaca, Chile, &c. A native nitrate of soda is obtained in great abundance in the district of Atacama and the province of Tarapaca, and is imported into Europe in enormous quantities as cubic nitre for the preparation of saltpetre.

Sodium phosphate and sulphate are cholagogue purgatives and are used in the treatment of gallstones.

The sulphate is the chief constituent of Marienbad and Carlsbad waters.

In the case of the Clark standard cell above mentioned the elements are mercury and zinc separated by a paste of mercurous sulphate mixed with a saturated solution of zinc sulphate.

In the Weston standard cell cadmium and cadmium sulphate are substituted for zinc and zinc sulphate; it has the advantage of a much smaller coefficient of temperature variation than the Clark cell.

The cadmium sulphate solution must be saturated and have free crystals of the salt in it.

The mercurous sulphate must be free from acid, and made neutral by trituration with finely divided mercury.

In making the paste, so much cadmium sulphate must be added that a saturated solution of that salt is formed and is present in the cell.

The legs are filled with solutions of zinc sulphate and copper sulphate, the zinc rod being in the zinc sulphate and the copper rod in the copper sulphate.

The solutions are made by dissolving the purest recrystallized sulphate of copper and sulphate of zinc in distilled water.

For the zinc solution, take 55.5 parts by weight of crystals of zinc sulphate (ZnS0470H2) and dissolve in 44.5 p arts by weight of distilled water; the resulting FIG.

For the sulphate of copper solution, take 16.5 parts by weight of pure crystals of copper sulphate (CuSO 4 50H 2) and dissolve in 83.5 parts by weight of water; the resulting solution should have a specific gravity of 1.

In the oceans alone there are estimated to be 1141 X 10 12 tons of sulphate, K 2 SO 4, but this inexhaustible store is not much drawn upon; and the "salt gardens" on the coast of France lost their industrial importance as potash-producers since the deposits at Stassfurt in Germany have come to be worked.

All commercial caustic potash is contaminated with excess of water (over and above that in the KHO) and with potassium carbonate and chloride; sulphate, as a rule, is absent.

It is worked up either for Epsom salt and common salt, or for sodium sulphate and magnesium chloride.

If the original solution contained the chlorides of magnesium or calcium or sulphate of potassium all impurities remain in the mother-liquor (the sulphur as KHS04), and can be removed by washing the precipitate with strong hydrochloric acid.

The commercial salt usually has an alkaline reaction; it may be purified by dissolving in the minimum amount of water, and neutralizing with dilute sulphuric acid; alcohol is now added to precipitate the potassium sulphate, the solution filtered and crystallized.

This product, known as "crude potashes," contains, in addition to carbonate, varying amounts of sulphate and chloride and also insoluble matter.

Crude potash is used for the manufacture of glass, and, after being causticized, for the making of soft soap. For many other purposes it must be refined, which is done by treating the crude product with the minimum of cold water required to dissolve the carbonate, removing the undissolved part (which consists chiefly of sulphate), and evaporating the clear liquor to dryness in an iron pan.

Potassium sulphide, K 2 S, was obtained by Berzelius in pale red crystals by passing hydrogen over potassium sulphate, and by Berthier as a flesh-coloured mass by heating the sulphate with carbon.

Liver of sulphur or hepar sulphuris, a medicine known to the alchemists, is a mixture of various polysulphides with the sulphate and thiosulphate, in variable proportions, obtained by gently heating the carbonate with sulphur in covered vessels.

The salt K2S03 H20 may be obtained by crystallizing the metabisulphite, K 2 S 2 0 5 (from sulphur dioxide and a hot saturated solution of the carbonate, or from sulphur dioxide and a mixture of milk of lime and potassium sulphate) with an equivalent amount of potash.

Potassium sulphate, K2S04, a salt known early in the 14th century, and studied by Glauber, Boyle and Tachenius, was styled in the 17th century arcanum or sal duplicatum, being regarded as a combination of an acid salt with an alkaline salt.

The acid sulphate or bisulphate, Khso 4, is readily produced by fusing thirteen parts of the powdered normal salt with eight parts of sulphuric acid.

An excess of alcohol, in fact, precipitates normal sulphate (with little bisulphate) and free acid remains in solution.

The tartrate and acid tartrate are also diuretic in their action and, as well as the sulphate, are valuable hydragogue saline purgatives.

The sulphocyanide is converted into the potassium salt by adding potassium sulphate, and finally desulphurized by lead, zinc, or iron.

Bueb (Congress of German Gas Industries, March 1900) brings gas (free from tar) into intimate contact with a saturated solution of ferrous sulphate, when a "cyanogen mud" is obtained.

It can be estimated quantitatively by mixing a dilute solution with potassium iodide and hydrochloric acid in excess, adding excess of zinc sulphate, neutralizing the excess of free acid with sodium bicarbonate, and determining the amount of free iodine by a standard solution of sodium thiosulphate.

The metallic cyanides may be detected by adding ferrous sulphate, ferric chloride, and hydrochloric acid to their solution, when a precipitate of Prussian blue is produced; if the original solution contains free acid it must be neutralized by caustic potash before the reagents are added.

He should keep his bowels regular, or even loose, taking every morning a dose of sulphate of soda in a glass of hot water.

It is doubtful if drugs have any direct influence upon gall-stones, such as sulphate of soda, olive oil or oleate of soda.

Chromous sulphate, CrS04 7H 2 0, isomorphous with ferrous sulphate, results on dissolving the metal in dilute sulphuric acid or, better, by dissolving chromous acetate in dilute sulphuric acid, when it separates in blue crystals on cooling the solution.

The hydrated fluoride, CrF3.9H20, obtained by adding ammonium fluoride to cold chromic sulphate solution, is sparingly soluble in water, and is decomposed by heat.

Chromic sulphate, Cr2(S04)3, is prepared by mixing the hydroxide with concentrated sulphuric acid and allowing the mixture to stand, a green solution is first formed which gradually changes to blue, and deposits violet-blue crystals, which are purified by dissolving in water and then precipitating with alcohol.

If the violet solution is allowed to evaporate slowly at ordinary temperatures the sulphate crystallizes out as Cr2(S04)3.15H20, but the green solution on evaporation leaves only an amorphous mass.

Chromium ammonium sulphate, (NH4)2S04 Cr2(S04)3.24H20, results on mixing equivalent quantities of chromic sulphate and ammonium sulphate in aqueous solution and allowing the mixture to crystallize.

By the action of concentrated sulphuric acid it is transformed into chromium ammonium sulphate.

This is used as the sulphate, which has the empirical formula of (C15H21N302)2, H 2 SO 4, plus an unknown number of molecules of water.

For the use of the oculist, who constantly employs this drug, it is also prepared in lamellae for insertion within the conjunctival sac. Each of these contains one-thousandth part of a grain of physostigmine sulphate, a quantity which is perfectly efficient.

By the reduction of ortho-nitrobenzaldehyde with ferrous sulphate and ammonia, ortho-aminobenzaldehyde is obtained.

It may be prepared by dissolving the metal, its oxide, hydroxide, or carbonate in dilute hydrochloric acid, or by mixing concentrated solutions of magnesium sulphate and common salt, and cooling the mixture rapidly, when the less soluble sodium sulphate separates first.

By - adding sodium phosphate to magnesium sulphate and allowing the mixture to stand, hexagonal needles of MgHPO 4.7H 2 O are deposited.

It may be prepared by adding normal sodium phosphate to a magnesium salt and boiling the precipitate with a solution of magnesium sulphate.

It is prepared by adding sodium phosphate to magnesium sulphate in the presence of ammonia and ammonium chloride.

Thus he clearly described the preparation of hydrochloric acid by the action of oil of vitriol on common salt, the manifold virtues of sodium sulphate - sal mirabile, Glauber's salt - formed in the process being one of the chief themes of his Miraculum mundi; and he noticed that nitric acid was formed when nitre was substituted for the common salt.

With this pile he decomposed sulphate of magnesia (first letter to Abbott, July 12, 1812).

A familiar example is to be found in solutions of sodium sulphate, which may be cooled much below their saturation point and kept in the liquid state till a crystal of the hydrate Na 2 SO 4 IoH 2 O is dropped in, when solidification occurs with a large evolution of latent heat.

It was found, for instance, that a film of insoluble copper ferrocyanide, deposited in the walls of a porous vessel by the inward diffusion and meeting of solutions of copper sulphate and potassium ferrocyanide, would allow water to pass, but retained sugar dissolved in that liquid.

Blue or Roman vitriol ' is copper sulphate; green vitriol, ferrous sulphate (copperas); white vitriol, zinc sulphate; and vitriol of Mars is a basic iron sulphate.

In practice the theoretical quantity of acid and Chile saltpetre is not used, but the charge is so regulated that the mixture of acid and neutral sodium sulphate formed in the retort remains liquid at the temperature employed, and consequently can be readily removed.

They may be recognized by the fact that on the addition of a solution of ferrous sulphate, followed by that of concentrated sulphuric acid (the mixture being kept quite cold), the ferrous sulphate solution becomes of a deep brown colour, owing to the reducing action of the ferrous sulphate on the nitric acid which is liberated by the action of the sulphuric acid on the nitrate.

The matter was carefully investigated, and it was found that the sulphate of magnesia in the sea-water has a decomposing action on Portland cements, especially those which contain a large proportion of lime or even of alumina.

Since then (1904) Miss Florence Durham has shown that if the skins of young or embryonic mammals (rats, rabbits and guinea-pigs) be ground up and extracted in water, and the expressed juice be then incubated with solid tyrosin for twentyfour hours, with the addition of a very small amount of ferrous sulphate to act as an activator, a pigmentary substance is thrown down.

The residue, consisting of alumina and potassium sulphate, was leached with water to separate the insoluble matter which was dried as usual.

All the by-products, potassium sulphate, sulphur and aluminate of iron, were capable of recovery, and were claimed to reduce the cost of the oxide materially.

Crystallized alumina is also obtained by heating the fluoride with boron trioxide; by fusing aluminium phosphate with sodium sulphate; by heating alumina to a dull redness in hydrochloric acid gas under pressure; and by heating alumina with lead oxide to a bright red heat.

Aluminium sulphate Al(S04)3, occurs in the mineral kingdom as keramohalite, Al 2 (SO 4) 3.1811 2 0, found near volcanoes and in alum-shale; aluminite or websterite is a basic salt, Al 2 (SO 4) (OH)4.71120.

Aluminium sulphate, known commercially as "concentrated alum" or "sulphate of alumina," is manufactured from kaolin or china clay, which, after roasting (in order to oxidize any iron present), is heated with sulphuric acid, the clear solution run off, and evaporated.

Aluminium sulphate crystallizes as Al 2 (SO 4) 3.181120 in tablets belonging to the monoclinic system.

On heating, the crystals lose water, swell up, and give the anhydrous sulphate, which, on further heating, gives alumina.

It is largely supplied in all the most fertilizing of organic manures, but when required in the inorganic state must be obtained from some of the salts of ammonia, as the sulphate, the muriate or the phosphate, all of which, being extremely energetic, require to be used with great caution.

The most commonly used nitrogenous manures are nitrate of soda, nitrate of potash and sulphate of ammonia, the prices of which are constantly fluctuating.

Cheaper substitutes, however, are now found in sulphate of potash, and muriate of potash and kainit.

Gypsum, or sulphate of lime, applied as a top-dressing at the rate of 2 to 3 cwt.

Another kind of alteration which pyrites may suffer has been termed "vitriolization," since the products are ferrous sulphate, with free sulphuric acid and sometimes a basic ferric sulphate.

Many fossils are mineralized with pyrites, which has evidently been reduced by the action of decomposing organic matter on a solution of ferrous sulphate, or perhaps less directly on ferrous carbonate dissolved in water containing carbonic acid, in the presence of certain sulphates.

The sulphate and chloride are similar, but they are not quite so unstable as the nitrate.

Jeweller's rouge for polishing plate is a fine red iron oxide prepared by calcination from ferrous sulphate (green vitriol).

It is a colourless oily liquid of strongly acid reaction; its aqueous solution decomposes on standing and on heating it forms diethyl sulphate and sulphuric acid.

While the proportion of common salt to sulphate of magnesia is as r r to r in the water of the Black Sea and as 2 to 1 in the Caspian water generally, it is as 12.8 to 5.03 in the Kara-boghaz.

In these cases the zinc sulphide has probably arisen from the reduction of sulphate by organic matter.

Lanthanum oxide, La203, is a white powder obtained by burning the metal in oxygen, or by ignition of the carbonate, nitrate or sulphate.

The sulphate is obtained by dissolving the oxide in sulphuric acid; if the solution be not acid, it separates in pyramidal crystals of composition BeSO 4.4H 2 0, while from an acid solution of this salt, crystals of composition BeS04.7H 2 O are obtained.

The nitrate Be(NO,)2.3H20 is prepared by adding barium nitrate to ber y llium sulphate solution; it crystallizes with difficulty and is very deliquescent.

Moraht (Berichte, 1890, 23, p. 2 55 6) from the conversion of the sulphate BeSO 4.4H 2 O into the oxide, from which they obtained the value 9.05.

The official doses of atropine are from to 1+F grain, and the sulphate, which is in general use in medicine, has a similar dose.

The anhidrotic action of atropine is largely employed in controlling the night-sweats so characteristic of pulmonary tuberculosis, small doses of the solution of the sulphate being given at night.

This goes on till a density of 1.1315 is attained, when hydrated calcium sulphate begins to deposit, and continues till specific gravity 1.2646 is reached.

At a density of 1.218 the deposit becomes augmented by sodium chloride, which goes down mixed with a little magnesium chloride and sulphate.

By night the liquor gives nearly pure magnesium sulphate; in the day the same sulphate mixed with sodium and potassium chlorides is deposited.

The mother-liquor now falls to a specific gravity of 1.3082 to 1.2965, and yields a very mixed deposit of magnesium bromide and chloride, potassium chloride and magnesium sulphate, with the double magnesium and potassium sulphate, corresponding to the kainite of Stassfurt.

At times sodium sulphate is added to the brine, producing sodium chloride and magnesium sulphate by double decomposition with the magnesium chloride.

Nothing is added during or after grinding save a small amount (I to 2%) of calcium sulphate in the form either of gypsum or of plaster of Paris, which is sometimes needed to make the cement slower-setting.

Under this term are comprehended all cements whose setting properties primarily depend on the hydration of calcium sulphate.

In a few minutes the surplus hydrated calcium sulphate is deposited from the solution, and the water is capable again of dissolving 2CaS04 H 2 O, which in turn is fully hydrated and deposited as CaS04.2H20.

The principles which govern the preparation and setting of the other class of calcium sulphate cements, that is, cements of the Keene class, are not fully understood, but there is a fair amount of knowledge on the subject, both empirical and scientific. The essential difference between the setting of Keene's cement and that of plaster of Paris is that the former takes place much more slowly, occupying hours instead of minutes, and the considerable heating and expansion which characterize the setting of plaster of Paris are much less marked.

The quantity of these materials is so small that analyses of Keene's cement show it to be almost pure anhydrous calcium sulphate, and make it difficult to explain what, if any, influence these minute amounts of alum and the like can exert on the setting of the cement.

The setting of Keene's cement takes place by the same sort of process which has been described for the setting of plaster of Paris, the chief differences being that the substance dissolved is anhydrous calcium sulphate and that the operation takes a longer time.

All cements having calcium sulphate as their base are suitable only for indoor work because of the solubility of this substance.

For the extraction of the metal from chamber mud, the latter is boiled with water, which extracts the thallium as the sulphate.

Thallous hydroxide, T10H, is most conveniently prepared by decomposing the solution of the sulphate with baryta water.

Thallous sulphate, T1 2 SO 4, forms rhombic prisms, soluble in water, which melt at a red heat with decomposition, sulphur dioxide being evolved.

Thallic sulphate, T1 2 (SO 4) 3.7H 2 O, and thallic nitrate, Tl(NO 3) 3.8H 2 0, are obtained as colourless crystals on the evaporation of a solution of the oxide in the corresponding acid.

The sulphate decomposes into sulphuric acid and the trioxide on warming with water, and differs from aluminium sulphate in not forming alums.

In this reaction urea is heated in a dry tube until it gives off ammonia freely; the residue is dissolved in water, made alkaline with caustic soda, and a drop of copper sulphate solution is added, when a fine violet-red coloration is produced.

Oxygen may be prepared by heating mercuric oxide; by strongly heating manganese dioxide and many other peroxides; by heating the oxides of precious metals; and by heating many oxy-acids and oxy-salts to high temperatures, for example, nitric acid, sulphuric acid, nitre, lead nitrate, zinc sulphate, potassium chlorate, &c. Potassium chlorate is generally used and the reaction is accelerated and carried out at a lower temperature by previously mixing the salt with about one-third of its weight of manganese dioxide, which acts as a catalytic agent.

Manganous Sulphate, MnSO 4, is prepared by strongly heating a paste of pyrolusite and concentrated sulphuric acid until acid fumes cease to be evolved.

The ferric and aluminium sulphates present are thus converted into insoluble basic salts, and the residue yields manganous sulphate when extracted with water.

It crystallizes in large pink crystals, the colour of which is probably due to the presence of a small quantity of manganic sulphate or of a cobalt sulphate.

With potassium sulphate in the presence of sulphuric acid it forms potassium manganese alum, K2S04 Mn2(S04)3.24H20.

Boucherie, a Frenchman, originated a system in which the sap is expelled from the timber under pressure, and a strong solution of copper sulphate is then injected at the end of the wood.

From the crude oxide so obtained (which contains lanthanum and didymium oxides) the cerium may be separated by conversion into its double sulphate on the addition of potassium sulphate, the sulphates of the cerium group being insoluble in a saturated solution of potassium sulphate.

The sulphate is subsequently boiled with water, when a basic sulphate is precipitated.

Cerium dioxide, Ce02, is produced when cerium carbonate, nitrate, sulphate or oxalate is heated in air.

A higher hydrated oxide, CeO 3 xH 2 O, is formed by the interaction of cerous sulphate with sodium acetate and hydrogen peroxide (Lecoq de Boisbaudran, Comptes rendus, 1885, loo, p. 605).

Many hydrated forms of the sulphate are known, as are also double salts of the sulphate with potassium, sodium, ammonium, thallium and cadmium sulphates.

The sulphate, Ce(SO 4) 2.4H 2 O, is formed when the basic sulphate is dissolved in sulphuric acid; or when the dioxide is dissolved in dilute sulphuric acid, and evaporated in vacuo over sulphuric acid.

The bark possesses tanning properties, and in Scotland in past times yielded with ferrous sulphate a black dye for wool.

The word " alkali " denotes both soda and potash, but by "alkali manufacture" we understand merely the manufacture of sodium sulphate, carbonate and hydrate.

The term alkali is employed in a technical sense for the carbonate and hydrate (of sodium), but since in the Leblanc process the manufacture of sodium sulphate necessarily precedes that of the carbonate, we include this as well as the manufacture of hydrochloric acid which is inseparable from it.

The sodium sulphate is afterwards fluxed with calcium carbonate and coal, and a mixture is thus obtained from which sodium carbonate can be extracted by exhausting it with water.

The rise of the ammonia-soda process (since 1870) gradually told upon the Leblanc process, which in consequence has been greatly restricted in Great Britain and Germany, and has become practically extinct in all other countries, except as far as its first part, the manufacture of sodium sulphate and hydrochloric acid, is concerned.

At first principally acid sodium sulphate, NaHSO 4, is formed together with some normal sulphate; later, when the temperature has risen, the NaHSO 4 acts with more NaC1 so that nearly all of it is converted into Na 2 SO 4.

The sulphuric acid present is mostly precipitated as calcium sulphate.

The clear caustic soda liquor must be concentrated in such a way that the caustic soda cannot to any great extent be reconverted into sodium carbonate, and that the " salts " which it contains, sodium carbonate, sulphate, chloride, &c., can be separated during the process.

The sulphate of quinine and the cinchona febrifuge thus produced are issued for the most part to medical officers in the various provinces, to gaols, and to the authorities of native states; but a large and increasing amount is disposed of in the form of 5-grain packets, costing a farthing each, through the medium of the post-offices.

The sulphate combines with the alkaline sulphates to form double salts of the type Sc 2 (SO 4) 3.3K 2 SO 4.

The metal is obtained from zinc blende (which only contains it in very small quantity) by dissolving the mineral in an acid, and precipitating the gallium by metallic zinc. The precipitate is dissolved in hydrochloric acid and foreign metals are removed by sulphuretted hydrogen; the residual liquid being then fractionally precipitated by sodium carbonate, which throws out the gallium before the zinc. This precipitate is converted into gallium sulphate and finally into a pure specimen of the oxide, from which the metal is obtained by the electrolysis of an alkaline solution.

Hypodermic tabloids of morphine sulphate either alone or combined with atropine are much in use.

Thorium sulphate, Th(S04)2, is obtained by dissolving the oxide in sulphuric acid.

Evaporation of a solution at ordinary temperatures gives colourless monoclinic prisms of Th(SO 4) 2.9H 2 O, which is isomorphous with uranium sulphate, U(S04)2.9H20.

Thorium sulphate forms double salts with the alkaline sulphates.

Berzelius found 235.5; Delafontaine, 229.7; Cleve, 232.6 by analyses of the sulphate, and 232.2 by analyses of the oxalate.

Kriiss and Nilson derived the value 230.7 (H = I) from analyses of the carefully purified sulphate.

When the former is used it is roasted with calcium sulphate or alkali waste to form a matte which is then blown in a Bessemer converter or heated in a reverberatory furnace with a siliceous flux with the object of forming a rich nickel sulphide.

The monoxide, NiO, occurs naturally as bunsenite, and is obtained artificially when nickel hydroxide, carbonate, nitrate or sulphate is heated.

A subsulphide, Ni 2 S(?), results when the sulphate is heated with sulphur or when the precipitated monosulphide is heated in a current of hydrogen.

When prepared by the precipitation of nickel salts with alkaline sulphide in neutral solution it is a greyish black amorphous compound which readily oxidizes in moist air, forming a basic nickel sulphate.

Nickel sulphate, NiSO 4, is obtained anhydrous as a yellow powder when any of its hydrates are heated.

Cyanogen iodide and iodine monoand tri-chloride effect similar decompositions with simultaneous liberation of iodine; sulphuric acid reacts slowly, forming nickel sulphate and liberating hydrogen and carbon monoxide.

Rubidium hydroxide, RbOH, is a colourless solid which is formed by the action of rubidium on water, or by the addition of baryta water to a solution of rubidium sulphate.

Iodine, antimony trichloride, molybdenum pentachloride, ferric chloride, ferric oxide, antimony, tin, stannic oxide and ferrous sulphate have all been used as chlorine carriers.

The water is bitter and undrinkable, being largely impregnated with carbonate and sulphate of soda with some borax.

Besides the dryers already mentioned, lead acetate, manganese borate, manganese dioxide, zinc sulphate and other bodies are used.

The main result of plastering is that the soluble tartrates in the wine are decomposed, forming insoluble tartrate of lime and soluble sulphate of potash.

Sulphuric and hydrochloric acids have little or no action upon it at ordinary temperatures, even when in a fine state of division; but on heating, copper sulphate and sulphur dioxide are formed in the first case, and cuprous chloride and hydrogen in the second.

The ores of any economic importance contain the copper either as oxide, carbonate, sulphate or sulphide.

Ores in which the copper is present as oxide or carbonate are soluble in sulphuric or hydrochloric acids, ferrous chloride, ferric sulphate, ammoniacal compounds and sodium thiosulphate.

Ferrous chloride is not much used; the Douglas-Hunt process uses a mixture of salt and ferrous sulphate which involves the formation of ferrous chloride, and the new Douglas-Hunt process employs sulphuric acid in which ferrous chloride is added after leaching.

When most of the copper has been converted into the sulphate, the ore is lixiviated.

In the original form of the Douglas-Hunt process, ferrous chloride was formed by the interaction of sodium chloride (common salt) with ferrous sulphate (green vitriol), the sodium sulphate formed at the same time being removed by crystallization.

If calcium chloride be used the precipitated calcium sulphate must be removed by filtration.

The precipitation of the copper from the solution, in which it is present as sulphate, or as cuprous and cupric chlorides, is generally effected by metallic iron.

Ores in which the copper is present as sulphate are directly lixiviated and treated with iron.

Copper sulphide may be converted either into the sulphate, which is soluble in water; the oxide, soluble in sulphuric or hydrochloric acid; cupric chloride, soluble in water; or cuprous chloride, which is soluble in solutions of metallic chlorides.

It may also be accomplished by calcination with ferrous sulphate, or other easily decomposable sulphates, such as aluminium sulphate.

This consists in stacking the broken ore in heaps and adding a mixture of sodium sulphate and ferric chloride in the proportions necessary for the entire conversion of the iron into ferric sulphate.

The sulphate, oxide or chlorides, which are obtained from the sulphuretted ores, are lixiviated and the metal precipitated fn the same manner as we have previously described.