Chapter XIII: Front Matter (13)

_c._ (Pharm. Journ.) Sulphate of magnesia and bicarbonate of soda, of each 1 lb.; tartaric acid, 1/2 lb.; mix as before. The last two are much less agreeable than the others.

4. Carbonate of magnesia, 2 parts; calcined magnesia, 4 parts; citric acid, 13 parts; lump sugar, 25 parts; essence of lemon, q. s. to flavour. Very agreeable. This is known as ‘ROGÉS PURGATIF,’

_Obs._ The above are very useful and popular medicines in indigestion, heartburn, nausea, habitual costiveness, dyspepsia, &c.——_Dose_, 1/2 to 2 dessert-spoonfuls, thrown into tumbler 3 parts filled with cold water, rapidly stirred and drank whilst effervescing, early in the morning fasting, or between breakfast and dinner.

=MAGNESIAN LEMONADE′.= See CITRATE OF MAGNESIA and LEMONADE (Aperient).

=MAGNESIUM.= Mg. _Syn._ MAGNIUM, TALCIUM. The metallic radical of magnesia. The existence of this metal was demonstrated by Sir H. Davy in 1808; but it was first obtained in sufficient quantity to examine its properties by Bussy in 1830.

_Prep._ 5 or 6 pieces of sodium, about the size of peas, are introduced into a test-tube, and covered with small fragments of chloride of magnesium; the latter is then heated to near its point of fusion, when the flame of the lamp is applied to the sodium, so that its vapour may pass through the stratum of heated chloride; when the vivid incandescence that follows is over, and the whole has become cold, the mass is thrown into water, and the insoluble metallic portion collected and dried.

Commercial magnesium is prepared by evaporating solution of the chlorides of sodium and magnesium, in the proportion of 1 to 3, to dryness, mixing with one quarter of its weight of fluor spar and a like amount of sodium, and heating to bright redness in an iron crucible of proper construction.

On a larger scale it is prepared by heating to redness a mixture of chloride of magnesium, 9 parts; fused chloride of sodium, 1-1/2 parts; fluoride of calcium, 1-1/2 parts; and sodium in slices, 1-1/2 parts.

_Prop., &c._ In colour and lustre it resembles silver, but in chemical properties is more like zinc; its sp. gr. is only 1·743; it is malleable; fusible at a red heat, and can be distilled like zinc; unaffected by dry air and by cold water; burns with brilliancy when heated to dull redness in air or oxygen gas, yielding oxide of magnesium; inflames spontaneously in chlorine, yielding chloride of magnesium; it dissolves in the acids with the evolution of hydrogen gas, and pure salts of magnesium result.

It has been used somewhat extensively as an illuminating agent for photographing at night, and also for the purpose of affording a brilliant light for microscopic and magic lantern effects.

=Magnesium, Bromide.= _Syn._ MAGNESII BROMIDUM. To bromide of iron in solution add calcined magnesia in excess, heat the mixture, filter, and evaporate the clear solution to dryness.

=Magnesium, Carbonate of (Light).= _Syn._ LIGHT CARBONATE OF MAGNESIA; CARBONATE OF MAGNESIA; MAGNESIA; MAGNESIÆ CARBONAS LEVIS (B. P.). 3MgCO_{3}.MgO.5H_{2}O. _Prep._ 1. (Ph. L.) Sulphate of magnesium, 4 lbs., and carbonate of sodium, 4 lbs. 9 oz.; boiling distilled water, 4 galls.; dissolve the salts separately in one half the water, filter, mix the solutions, and boil for 2 hours, constantly stirring with a spatula, distilled water being frequently added to compensate for that lost by evaporation; lastly, the solution being poured off, wash the precipitated powder with boiling distilled water, and dry it. The formulæ of the Ph. E. & D. are essentially the same, except that the ebullition is limited to from 10 to 20 minutes.

2. (B. P.) Similar to the foregoing except that precipitation takes place in the cold. The formula of this compound is (Mg.CO_{3})_{3}. Mg(HO)_{2}.4(H_{2}O).

3. (HENRY’S.) Ordinary carbonate of magnesia, the washing of which has been finished with a little rose water.

4. Add a solution of carbonate of potassium or sodium to the bittern or residuary liquor of the sea-salt works, and well wash and dry the precipitate as before. This is known in commerce as ‘Scotch magnesia.’

_Obs._ The carbonate of magnesia of commerce is usually made up into cakes or dice while drying; or it is permitted to drain and dry in masses, which are then cut into squares with a thin knife. It is powdered by simply rubbing it through a wire sieve. The presence of iron in the solution of the sulphate of magnesium, when the crude salt is employed, and which is destructive to the beauty of the preparation may be got rid of by the addition of lime water until the liquor acquires a slight alkaline reaction, and subsequent decantation after repose.

=Magnesium, Carbonate of (Heavy).= _Syn._ HEAVY CARBONATE OF MAGNESIA; MAGNESIÆ CARBONAS (B. P.). 3MgCO_{3}.MgO.5H_{2}O. _Prep._ 1. Apothecaries’ Hall. A saturated solution of sulphate of magnesium, 1 part, is diluted with water, 3 parts, and the mixture heated to the boiling point; a cold saturated solution of carbonate of sodium, 1 part (all by measure), is then added, and the whole is boiled with constant agitation until effervescence ceases; boiling water is next freely poured in, and after assiduous stirring for a few minutes, and repose, the clear liquid is decanted, and the precipitate thrown on a linen cloth and thoroughly washed with hot water; it is, lastly, drained, and dried in an iron pot.

2. (Ph. D.) Dissolve sulphate of magnesium, 10 oz., in boiling distilled water, 1/2 pint; and carbonate of sodium (cryst.), 12 oz., in boiling distilled water, 1 pint; mix the two solutions, and evaporate the whole to dryness by the heat of a sand bath; then add of boiling water 1 quart, digest with agitation for half an hour, and wash the insoluble residuum as before; lastly, drain it, and dry it at the temperature of boiling water.

3. (B. P.) White granular powder precipitated from a boiling solution of sulphate of magnesium by a solution of carbonate of sodium, the whole evaporated to dryness, and the dry residue digested in water, collected on a filter, and washed.

_Prop._ The ordinary or light carbonate of magnesia is a white, inodorous, tasteless powder, possessing similar properties to calcined magnesia, except effervescing with acids, and having less saturating power. An ounce measure is filled by 45 to 48 gr. of the powder lightly placed in it. The heavy carbonate is sometimes fully thrice as dense (see _below_), but in other respects is similar.

_Dose._ As an antacid, 1/2 to a whole teaspoonful, 3 or 4 times daily; as a laxative 1/2 dr. to 2 dr. It is commonly taken in milk. It is apt to produce flatulence, but in other respects is preferable to calcined magnesia.

_General Remarks._ Although commonly called ‘carbonate of magnesia,’ the above substance, whether in the light or heavy form, appears to be a compound of carbonate with hydrate, in proportions which are not perfectly constant. (For B. P. formula see preceding article.) On account of the excess of base in its composition it was formerly regarded as a subsalt (subcarbonate of magnesia). A great deal has been written uselessly respecting the preparation of these carbonates, about which, however, there is neither mystery nor difficulty, as some writers would lead their readers to suppose. If the solutions are very dilute, the precipitate is exceedingly light and bulky; if otherwise, it is denser. By employing nearly saturated solutions, and then heating them and mixing them together whilst very hot, a very heavy precipitate is obtained, but it is apt to be gritty or crystalline. The same occurs when cold solutions are mixed, and no heat is employed. The lightest precipitate is obtained from cold, highly dilute solutions, and subsequent ebullition of the mixture.

Mr Pattinson, a chemist of Gateshead, prepares a very beautiful and pure heavy carbonate from magnesian limestone. The latter is calcined at a dull red heat (not hotter) for some time, by which the carbonic anhydride is expelled from the carbonate of magnesium, but not from the carbonate of calcium, which hence continues insoluble. The calcined mass is next reduced to a milk with water in a suitable cistern, and the carbonic anhydride resulting from its own calcination forced into it under powerful pressure. The result is a saturated solution of carbonate of magnesia, the lime remaining unacted on so long as the magnesium is in excess. The solution by evaporation yields the heavy carbonate, whilst carbonic anhydride is expelled, and may be again used in the same manufacture. 154 to 160 gr. of the heavy carbonate are required to fill an ounce measure when lightly placed in it, by which it appears to be fully thrice as dense as the light carbonate. The bicarbonate of magnesium (magnesiæ bicarbonas, L.) exists only in solution. The so-called ‘fluid magnesias’ of Murray, Dinneford, Husband, &c., are solutions of this salt. The small prismatic crystals which are deposited when ‘fluid magnesia’ is exposed to the air for some time consist of hydrated neutral carbonate, and not bicarbonate, as is sometimes stated.

=Magnesium, Chloride of.= MgCl_{2}. _Syn._ MAGNESII CHLORIDUM, L. _Prep._ (Liebig.) By dissolving magnesia in hydrochloric acid, evaporating to dryness, adding an equal weight of chloride of ammonium, projecting the mixture into a red-hot platinum crucible, and continuing the heat till a state of tranquil fusion is attained. On cooling, it forms a transparent, colourless, and very deliquescent mass, which is anhydrous, and soluble in alcohol.

_Obs._ Without the addition of the chloride of ammonium it is impossible to expel the last portion of the water without at the same time driving off the chlorine, in which case nothing but magnesia is left. The fused mass should be poured out on a clean stone, and when solid broken into pieces, and at once transferred to a warm, dry bottle. The P. Cod. orders the solution to be evaporated to the sp. gr. 1·384, and to be put, whilst still hot, into a wide-mouthed flask to crystallise.——_Dose_, 1 to 4 dr.; as a laxative.

=Magnesium, Cit′rate of.= Mg_{3}(C_{6}H_{5}O_{7})_{2}. _Syn._ MAGNESIÆ CITRAS. L. _Prep._ There is some difficulty in obtaining this salt in an eligible form for medicinal purposes. When precipitated from a solution it is insoluble. The following formulæ can be highly recommended.

1. (Parrish.) Dissolve crystallised citric acid, 100 gr., in water, 15 drops, and its own ‘water of crystallisation’ by the aid of heat; then stir in calcined magnesia, 35 gr.; a pasty mass will result, which soon hardens, and may be powdered for use.

_Obs._ The chief practical difficulty in this process results from the great comparative bulk of the magnesia, and the very small quantity of the fused mass with which it is to be incorporated. A part of the magnesia is almost unavoidably left uncombined, and the salt is consequently not neutral. The uncombined earth should be dusted off the mass before powdering the latter. A high temperature must be avoided.

2. (Robiquet.) Citric acid, 35-1/4 parts, is powdered and dissolved in boiling water, 10-5/8 parts; when the solution is cold, and before it crystallises, it is poured in a wide earthen vessel, kept cold by surrounding it with water; then, by means of a sieve, carbonate of magnesium, 21-1/6 parts, is distributed evenly and rapidly over the surface without stirring; when the reaction ceases the mixture is beaten rapidly as long as it retains its pasty consistence. The salt should be dried at a temperature not exceeding 70° Fahr.

3. (Effervescing; MAGNESIÆ CITRAS EFFERVESCENS, L.)——_a._ Citric acid (dried and powdered), 7 parts; heavy carbonate of magnesium, 5 parts; mix, and preserve in well-corked bottles.

_b._ (Ellis.) Mix powdered citric acid, 2-1/2 oz., with powdered sugar, 8 oz.; triturate to a fine powder, and drive off the water of crystallisation by the heat of a water bath; add citrate of magnesium (prepared by fusion), 4 oz., and oil of lemons, 10 drops, and mix intimately; then add bicarbonate of sodium, 3 oz., and again triturate until the whole forms a fine powder, which must be preserved in stoppered bottles. From 1 to 3 tablespoonfuls, mixed in a tumbler of water, furnishes an effervescing draught in which the undissolved portion is so nicely suspended, that it can be taken without inconvenience.

_c._ (Ph. Germ.) Light carbonate of magnesia, 25 oz.; citric acid, 75 oz.; distilled water, q. s.; mix into a thick paste and dry at 86° Fahr. With 14 oz. of the dried mass mix bicarbonate of soda, 13 oz.; citric acid, 6 oz.; sugar, 3 oz. Sprinkle over the mixture enough rectified spirit so as to make it sufficiently moist to be granulated by rubbing through a tinned iron sieve.

_d._ (Extemporaneous.) Citric acid (cryst.), 20 gr.; carbonate of magnesium, 14 gr.; mix in a tumbler of cold water, and drink the mixture whilst effervescing. A pleasant saline.

_Obs._ A dry white powder, sometimes sold as citrate of magnesia in the shops, is quite a different preparation to the above, and does not contain a particle of citric acid. The following formula is that of a wholesale London drug-house that does largely in this article:——

Calcined magnesia, magnesium oxide, 1-1/4 lb. (or carbonate, 2 lbs.); powdered tartaric acid, 1-1/2 lb.; bicarbonate of sodium, 1 lb.; dry each article by a gentle heat, then mix them, pass the mixture through a fine sieve in a warm dry room, and keep it in well-corked bottles. A few drops of essence of lemon and 3 lbs. of finely powdered sugar are commonly added to the above quantity. This addition renders it more agreeable.

_Prop., &c._ Citrate of magnesium is a mild and agreeable laxative; its secondary effects resemble those of the carbonate.——_Dose._ As a purgative, 1/2 to 1 oz. The dose of the effervescing citrate must depend on the quantity of magnesia present. A solution of this salt in water, sweetened and flavoured with lemon, forms magnesian lemonade.

=Magnesium, Boro-cit′rate of.= _Syn._ MAGNESIÆ BORO-CITRAS, L. _Prep._ (Cadet.) Boracic acid (in powder), 113 gr.; oxide of magnesium, 80 gr.; mix in a porcelain capsule, and add enough of a solution of citric acid, 260 gr., in water, 3-1/2 pints, to form a thin paste; then add the remainder of the citric solution, and gently evaporate, with constant stirring, to dryness. A cooling saline, and, in small doses, emmenagogue and lithontriptic.——_Dose._ As an aperient, 3 to 6 dr.

=Magnesium, Oxide of.= MgO. _Syn._ OXIDE OF MAGNESIUM, CALCINED MAGNESIA, MAGNESIA (B. P., Ph. L.).

_Prep._ 1. (B. P.) Magnesium carbonate, heated in a crucible until all the carbonic anhydride is driven off.

_Prop., &c._ White heavy powder, scarcely soluble in water, but readily soluble in acids without effervescence. Its solution in hydrochloric acid, neutralised by a mixed solution of ammonia and ammonium chloride, gives a copious crystalline precipitate when sodium phosphate is added to it. See next preparation.

=Magnesia levis= (B. P.) _Syn._ LIGHT MAGNESIA. _Prep._ (B. P.) 1. Light carbonate of magnesium heated in a Cornish crucible until all the carbonic anhydride is driven off.

A bulky white powder, differing from the magnesia (B. P.) only in its density, the volume occupied by the same weight being 3-1/2 to 1.

The properties of the two varieties of magnesium oxide are identical, and are used in medicine as antacids, laxatives, and antilithics, and much used in dyspepsia, heartburn, &c.——_Dose_, 10 to 20 gr. as an antacid and 20 to 60 gr. as a purgative.

=Magnesium, Phos′phate of.= MgHPO_{4}.6Aq. _Syn._ MAGNESIÆ PHOSPHAS, L. _Prep._ From the mixed solutions of phosphate of sodium and sulphate of magnesium, allowed to stand for some time. Small, colourless, prismatic crystals, which, according to Graham, are soluble in about 1000 parts of cold water. Phosphate of magnesium exists in the grains of the cereals, and in considerable quantity in beer. It is also found in guano.

=Magnesium and Ammo′′nium, Phosphate of.= MgNH_{4}.PO_{4}, 6 Aq. _Syn._ AMMONIO-PHOSPHATE OF MAGNESIA; MAGNESIÆ ET AMMONIÆ PHOSPHAS, L. This compound falls as a white crystalline precipitate whenever ammonia or carbonate of ammonium is added, in excess, to a solution of a salt of magnesium which has been previously mixed with a soluble phosphate, as that of soda. It subsides immediately from concentrated solutions, but only after some time from very dilute ones.

_Prop., &c._ Ammonio-phosphate of magnesium is very slightly soluble in pure water; when heated, it is resolved into pyrophosphate of magnesium, and is vitrified at a strong red heat. It is found in wheaten bran, guano, potatoes, &c., and occasionally forms one of the varieties of urinary calculi.

=Magnesium, Sil′icates of.= There are several native silicates of magnesia, more or less pure, of which, however, none is directly employed in medicine. Meerschaum and steatite or soapstone are well-known varieties. Serpentine is a compound of silicate and hydrate of magnesium. The minerals augite and hornblende are double salts of silicic acid, magnesium, and calcium with some ferrous oxide. The beautiful crystallised mineral called chrysolite is a silicate of magnesium, coloured with ferrous oxide. Jade is a double silicate of magnesium and aluminum, coloured with chromic oxide.

=Magnesium, Sulphate of.= MgSO_{4}, 7 Aq. _Syn._ EPSOM SALT, MAGNESIÆ SULPHAS (B. P. Ph. L. E. & D.), SAL EPSOMENSIS, L. This compound was originally extracted from the saline springs of Epsom, Surrey, by Dr Grew, in 1695. It is now exclusively prepared on the large scale, and from either magnesian limestone or the residual liquor of the sea-salt works.

_Prep._ 1. From dolomite or magnesian limestone.——_a._ The mineral, broken into fragments, is heated with a sufficient quantity of dilute sulphuric acid to convert its carbonates into sulphates; the sulphate of magnesium is washed out of the mass with hot water, and the solution, after defecation, is evaporated and crystallised.

_b._ The ‘limestone,’ either simply broken into fragments or else calcined (burnt), and its constituents quicklime and oxide magnesium converted into hydrates by sprinkling (slaking) it with water, is treated with a sufficient quantity of dilute hydrochloric acid to dissolve out all the calcium hydrate without touching the magnesium hydrate; the residuum of the latter, after being washed and drained, is dissolved in dilute sulphuric acid, and crystallised as before.

2. From bittern.——_a._ The residual liquor or mother-water of sea-salt is boiled for some hours in the pans which are used during the summer for the concentration of brine; the saline solution is then skimmed and decanted from some common salt which has been deposited, after which it is concentrated by evaporation, and, finally, run into wooden coolers; in about 36 hours, 1-8th part of Epsom salts usually crystallises out. This is called ‘singles.’ By re-dissolving this in water, and re-crystallisation, ‘doubles,’ or Epsom salts fit for the market, are obtained. A second crop of crystals may be procured by adding sulphuric acid to the mother-liquor, and re-concentrating the solution, but this is seldom had recourse to in England. Bittern yields fully 5 parts of sulphate of magnesia for every 100 parts of common salt that has been previously obtained from it.

_b._ A concentrated solution of sulphate of sodium is added to bittern, in equivalent proportion to that of the chloride of magnesium in it, and the mixed solution is evaporated at the temperature of 122° Fahr. (Ure); cubical crystals of common salt are deposited as the evaporation proceeds, after which, by further concentration and repose, regular crystals of sulphate of magnesia are obtained.

_c._ A sufficient quantity of calcined and slaked magnesian limestone is boiled in bittern to decompose the magnesium salts, and the liquid is evaporated, &c., as before. This is a very economical process.

_Prop._ Small acicular crystals, or (by careful crystallisation) large four-sided rhombic prisms; colourless; odourless, transparent; slightly efflorescent; extremely bitter and nauseous; when heated, it fuses in its water of crystallisation, the larger portion of which readily passes off, but one equivalent of water is energetically retained; at a high temperature it runs into a species of white enamel; it dissolves in its own weight of cold water, and in 3-4ths of that quantity of boiling water; it is insoluble in both alcohol and ether. Sp. gr. 1·66.

_Pur._ Sulphate of magnesium is soluble in an equal weight of water at 60° Fahr., by which it may be distinguished from sulphate of sodium, which is much more soluble.

An aqueous solution in the cold is not precipitated by oxalate of ammonium. The precipitate given by carbonate of sodium from a solution of 100 gr. should, after well washing and heating to redness, weigh 16·26 gr. (B. P.)

Digested in alcohol, the filtered liquid does not yield a precipitate with nitrate of silver nor burn with a yellow flame, and evaporates without residue. “Not deliquescent in the air.” (Ph. L.) 100 gr. of the pure crystallised sulphate yields 16-1/4 gr. of calcined magnesium oxide. (Pereira.) 10 gr., dissolved in 1 fl. oz. of water, and treated with a solution of carbonate of ammonium, are not entirely precipitated by 280 minims of solution of phosphate of sodium. (Ph. E.)

_Uses, &c._ Sulphate of magnesium is an excellent cooling purgative, and sometimes proves diuretic and diaphoretic.——_Dose_, 1 dr. to 1 oz., as a purgative, or an antidote in poisoning by lead. Large doses should be avoided. Instances are on record of their having proved fatal. Dr Christison mentions the case of a boy 10 years old who swallowed 2 oz. of salts, and died within 10 minutes. The best antidote is an emetic. A small quantity of Epsom salts, largely diluted with water (as a drachm to 1/2 pint or 3/4 pint), will usually purge as much as the common dose. This increase of power has been shown by Liebig to result rather from the quantity of water than the salt. Pure water is greedily taken up by the absorbents; but water holding in solution saline matter is rejected by those vessels, and consequently passes off by the intestines.

_Obs._ Oxalic acid has occasionally been mistaken for Epsom salt, with fatal results. They may be readily distinguished from each other by the following characteristics:——

EPSOM SALT. | OXALIC ACID.
Tastes extremely bitter | Tastes extremely sour.
and nauseous. |
| Volatilises when heated
Does not volatilise | on platinum foil.
when heated on platinum |
foil. Does not | Produces milkiness
produce milkiness | when dissolved in
when dissolved in | _hard_ water.
_hard_ water. |

=Magnesium, Tar′trate of.= _Syn._ MAGNESIÆ TARTRAS, MAGNESIA TARTARICA, L. _Prep._ By saturating a solution of tartaric acid with carbonate of magnesium, and gently evaporating to dryness. It is only very slightly soluble in water.——_Dose_, 20 to 60 gr., or more; in painful chronic maladies of the spleen. (Pereira, ex Radmacher.) The effervescing tartrate of magnesium, commonly sold under the name citrate, has already been noticed.

=Magnesium and Potas′sium, Tartrate of.= _Syn._ POTASSIO-TARTRATE OF MAGNESIA; MAGNESIÆ POTASSIO-TARTRAS, M. ET POTASSÆ TARTRAS, L. _Prep._ From acid tartrate of potassium (in powder), 7 parts; carbonate of magnesium, 2 parts; water, 165 parts; boiled until the solution is complete, and then evaporated and crystallised. A mild aperient.——_Dose_, 1 to 5 dr.; in scurvy, &c.

=MAG′NET.= _Syn._ MAGNES, L. Besides its application to the loadstone, this name was formerly given to several compounds used in medicine.——ARSENICAL MAGNET (MAGNES ARSENICALIS), a substance once used as a caustic, consisted of common antimony, sulphur, and arsenious acid, fused together until they formed a sort of glass. MAGNES EPILEPSIÆ was native cinnabar.

=MAHOG′ANY.= This is the wood of _Swietenia Mahogoni_ (Linn.), a native of the hotter parts of the new world. It is chiefly imported from Honduras and Cuba. The extract is astringent, and has been used in tanning, and as a substitute for cinchona bark. The wood is chiefly employed for furniture and ornamental purposes, and, occasionally, in ship-building.

Imitations of mahogany are made by staining the surface of the inferior woods by one or other of the following methods:

1. Warm the wood by the fire, then wash it over with aquafortis, let it stand 24 hours to dry, and polish it with linseed oil reddened by digesting alkanet root in it; or, instead of the latter, give the wood a coat of varnish, or French polish which has been tinged of a mahogany colour with a little aloes and annotta.

2. Socotrine aloes, 1 oz.; dragon’s blood, 1/2 oz.; rectified spirit, 1 pint; dissolve, and apply 2 or 3 coats to the surface of the wood, previously well smoothed and polished; lastly, finish it off with wax or oil tinged with alkanet root.

3. Logwood, 2 oz.; madder, 8 oz.; fustic, 1 oz.; water, 1 gall.; boil 2 hours, and apply it several times to the wood boiling hot; when dry, slightly brush it over with a solution of pearlash, 1 oz.; in water, 1 quart; dry, and polish as before.

4. As the last, but using a decoction of logwood, 1 lb., in water, 5 pints. The tint may be brightened by adding a little vinegar or oxalic acid, and darkened by a few grains of copperas.

Stains and spots may be taken out of mahogany furniture with a little aquafortis or oxalic acid and water, by rubbing the part with the liquid by means of a cork till the colour is restored; observing afterwards to well wash the wood with water, and to dry it and polish it as before.

=MAIZE.= _Syn._ INDIAN CORN. The seeds of _Zea Mays_ (Linn.). Like the other corn plants, it belongs to the Grass family (_Graminaceæ_), and has albuminous grains sufficiently large and farinaceous to be ground into flour.

Maize is extremely nutritious, and although it is poorer in albumenoid matters than wheat, it is, of all the cereal grains, the richest in fatty oil, of which it contains about 9%. (Dumas and Payen.) It is remarkable for its fattening quality on animals, but is apt to excite slight diarrhœa in those unaccustomed to its use. Its meal is the ‘POLENTA’ of the shops. The peculiar starch prepared from it is known as ‘CORN FLOUR,’ In America the young ears are roasted and boiled for food.

The centesimal composition of maize is as follows:——Flesh formers (albumenoid bodies), 9·9; heat and fat formers (starch, dextrin, and fat), 71·2, fibre, 4·0; ash, 1·4; water, 13·5.

Letheby says of maize: “The grain is said to cause disease when eaten for a long time, and without other meal——the symptoms being a scaly eruption upon the hands, great prostration of the vital powers, and death after a year or so, with extreme emaciation.

These effects have been frequently observed amongst the peasants of Italy, who use the meal as their chief food, but I am not aware of any such effects having been seen in Ireland, where it is often the only article of diet for months together.”

Millions of bushels are grown every year in the United States of America, and large quantities are continually imported into England, where it is held in high esteem by cattle breeders, it being much cheaper than many of our home-grown productions. It is occasionally given to horses as a substitute for oats.

=MALAG′MA.= In _pharmacy_, a poultice or emollient application.

=MA′LIC ACID.= H_{3}C_{4}H_{3}O_{5}. _Syn._ ACIDUM MALICUM, L. This acid exists in the juice of many fruits and plants, either alone or associated with other acids, or with potassa or lime. In the juice of the garden rhubarb it exists in great abundance, being associated with acid oxalate of potassa.

_Prep._ (Everitt.) The stalks of common garden rhubarb are peeled, and ground or grated to a pulp, which is subjected to pressure; the juice is heated to the boiling point, neutralised with carbonate of potassa, mixed with acetate of lime, and the insoluble oxalate of lime which falls is removed by filtration; to the clear and nearly colourless liquid, solution of acetate of lead is next added as long as a precipitate (‘malate of lead’) continues to form; this is collected on a filter, washed, diffused through water, and decomposed by sulphuric acid, avoiding excess, the last portion of lead being thrown down by a stream of sulphuretted hydrogen; the filtered liquid is, lastly, carefully evaporated to the consistence of a syrup, and left in a dry atmosphere until it becomes converted into a solid and somewhat crystalline mass of malic acid. If perfectly pure malic acid is required, the malate of lead must be crystallised before decomposing it with sulphuretted hydrogen. _Prod._ 20,000 gr. of the peeled stalks yield 12,500 gr. of juice, of which one imperial gallon contains 11,139-1/4 gr. of dry malic acid.

_Obs._ By a similar process malic acid may be prepared from the juice of thee berries of the mountain ash (_Sorbus aucuparia_), just when they commence to ripen, or from the juice of apples, pears, &c.

_Prop., &c._ Malic acid is slightly deliquescent, very soluble in water, soluble in alcohol, and has a pleasant acidulous taste. The aqueous infusion soon gets mouldy by keeping. When kept fused for some time at a low heat, it is converted into fumaric acid; and when quickly distilled, it yields maleic acid, while fumaric acid is left in the retort. With the bases malic acid forms salts called malates. Of these the acid malate of ammonia is in large, beautiful crystals; malate of lead is insoluble in cold water, but dissolves in warm dilute acid, from which it separates on cooling in brilliant silvery crystals; acid malate of lime also forms very beautiful crystals, freely soluble in water; neutral malate of lime is only sparingly soluble in water; the first is obtained by dissolving the latter in hot dilute nitric acid, and allowing the solution to cool very slowly.

=MALLEABIL′ITY.= The peculiar property of metals which renders them capable of extension under the hammer.

=MALT.= _Syn._ BINA, BYNE, BRASIUM, MALTUM, L. The name given to different kinds of grain, such as barley, bere or bigg, oats, rye, maize, &c., which have become sweet, from the conversion of a portion of their starch into sugar, in consequence of incipient germination artificially produced. Barley is the grain usually employed for this purpose.

_Var._ Independently of variations of quality, or of the grain from which it is formed, malt is distinguished into varieties depending on the heat of the kiln employed for its desiccation. When dried at a temperature ranging between 90° and 120° Fahr., it constitutes ‘PALE MALT,’ when all the moisture has exhaled, and the heat is raised to from 125° to 135°, ‘YELLOW,’ or ‘PALE AMBER MALT,’ is formed; when the heat ranges between 140° and 160°, the product receives the name of ‘AMBER MALT,’ at 160° to 180°, ‘AMBER-BROWN,’ or ‘PALE BROWN MALT,’ is obtained. ROASTED, PATENT, or BLACK MALT, and CRYSTALLISED MALT, are prepared by a process similar to that of roasting coffee. The malt is placed in sheet-iron cylinders over a strong fire, and the cylinders made to revolve at the rate of about 20 revolutions per minute if roasted malt is required, or 120 for crystallised malt. In the former case the finished malt has a dark brown colour; in the latter, the interior of the grain becomes dark brown, whilst the husk assumes a pale amber hue. The temperature must never exceed 420°, or the malt will become entirely carbonised.

_Qual._ Good malt has an agreeable smell and a sweet taste. It is friable, and when broken discloses a floury kernel. Its husk is thin, clean, and unshrivelled in appearance, and the acrospire is seen extending up the back of the grain, beneath the skin. The admixture of unmalted with malted grain may be discovered, and roughly estimated, by throwing a little into water, malt floats on water, but barley sinks in it. The only certain method, however, of determining the value of malt is to ascertain the amount of soluble matter which it contains, by direct experiment. This varies from 62 to 70%, and for good malt is never less than 66 to 67%. If we assume the quarter of malt at 324 lbs., and the average quantity of soluble matter at 66%, then the total weight of soluble matter will be fully 213-3/4 lbs. per quarter; but as this, “in taking on the form of gum and sugar” during the process of mashing, “chemically combines with the elements of water, so the extract, if evaporated to dryness, would reach very nearly 231 lbs.; and this reduced to the basis of a barrel of 36 gallons, becomes in the language of the brewer, 87 lbs. per barrel, which, however, merely means that the wort from a quarter of malt, if evaporated down to the bulk of a barrel of 36 gallons, would weigh 87 lbs. more than a barrel of water.” (Ure.)

_Assay._ 1. A small quantity of the sample being ground in a coffee or pepper mill, 100 gr. are accurately weighed, and dried by exposure for about 1 hour at the temperature of boiling water. The loss in weight, in grains, indicates the quantity of moisture per cent. This, in good malt, should not exceed 6-1/2 gr.

2. A second 100 gr. is taken and stirred up with about 1/2 pint of cold water; the mixture is then exposed to the heat of boiling water for about 40 minutes; after which it is thrown on a weighed filter, and the undissolved portion washed with a little hot water; the undissolved portion, with the filter, is then dried at 212° Fahr., and weighed. The loss in weight, less the percentage of moisture last found, taken in grains, gives the percentage of soluble matter. This should not be less than 66 gr. The same result will be arrived at by evaporating the filtered liquid and ‘washings’ to dryness, and weighing the residuum.

3. A third 100 gr. is taken and mashed with about 1/2 pint of water at 160° Fahr., for 2 or 3 hours; the liquid is then drained off, the residue gently squeezed, and the strained liquid evaporated to dryness, as before, and weighed. This gives the percentage of saccharine matter, and should not be less than about 71 gr., taking the above average of malt as the standard of calculation.

_Uses, &c._ Malt is chiefly employed in the arts of brewing and distillation. Both roasted and crystallised malt are merely used to colour the worts produced from pale malt. 1 lb. of roasted malt, mashed with 79 lbs. of pale malt, imparts to the liquor the colour and flavour of ‘porter.’ The paler varieties of malt contain the largest quantity of saccharine matter. After the malt has been kiln-dried, the rootlets may be removed by means of a sieve. Before malt is mashed for beer it must be broken up, and the law requires that it be bruised or crushed by smooth metal rollers, and not ground by millstones. It has also been proposed to employ malt, instead of raw grain, for fattening domestic animals, and as food for their young and those in a sickly state. Infusion of malt (sweet wort, malt tea) is laxative, and has been recommended as an antiscorbutic and tonic. It has been given with great advantage in scurvy; but for this purpose good, well-hopped, mild beer is equally serviceable and more agreeable. See BREWING, DISTILLATION, FERMENTATION, &c.

=MALT LIQ′UORS.= The qualities of ale, beer, and porter, as beverages, the detection of their adulteration, and the methods of preparing them, are described under their respective names and in the article upon ‘BREWING’; the present article will, therefore, be confined to a short notice of the cellar management, and the diseases of malt liquors generally.

AGE. The appearance and flavour to which this term is applied can, of course, be only given to the liquor by properly storing it for a sufficient time. Fraudulent brewers and publicans, however, frequently add a little oil of vitriol (diluted with water) to new beer, by which it assumes the character of an inferior liquor of the class 1 or 2 years old. Copperas, alum, sliced onions, Seville oranges, and cucumbers, are also frequently employed by brewers for the same purpose.

BOTTLING. Clean, sweet, and dry bottles, and sound and good corks, should be had in readiness. The liquor to be bottled should be perfectly clear; and if it be not so, it must be submitted to the operation of ‘fining.’ When quite fine, and in good condition, the bung of the cask should be left out all night, and the next day the liquor should be put into bottles, which, after remaining 12 or 24 hours, covered with sheets of paper to keep out the flies and dust, must be securely corked down. Porter is generally wired over. The wire for this purpose should be ‘annealed,’ and not resilient. If the liquor is intended for exportation to a hot climate, the bottles should remain filled for 2 or 3 days, or more, before corking them. The stock of bottled liquor should be stored in a cool situation; and a small quantity, to meet present demands only, should be set on their sides in a warmer place to ripen. October beer should not be bottled before Midsummer, nor March beer till Christmas.

CLOUDINESS. Add a handful of hops boiled in a gallon of the beer, and in a fortnight fine it down.

FINING. See CLARIFICATION and BREWING.

FLATNESS. When the liquor is new, or has still much undecomposed sugar left in it, a sufficient remedy is to remove it into a warmer situation for a few days. When this is not the case, 2 or 3 pounds of moist sugar (foots) may be ‘rummaged’ into each hogshead. In this way a second fermentation is set up, and in a few days the liquor becomes brisk, and carries a head. This is the plan commonly adopted by publicans. On the small scale the addition of a few grains of carbonate of soda, or of prepared chalk, to each glass, is commonly made for the same purpose; but in this case the liquor must be drunk within a few minutes, else it becomes again flat and insipid. This may be adopted for home-brewed beer which has become sour and vapid.

FOXING OR BUCKING. The spontaneous souring of worts or beer during their fermentation or ripening, to which this name is applied, may generally be remedied by adding to the liquor some fresh hops (scalded), along with some black mustard seed (bruised). Some persons use a little made mustard, or a solution of alum or of catechu, and in a week or 10 days afterwards further add some treacle, or moist sugar.

Frosted beer is recovered by change of situation; by the addition of some hops boiled in a little sweet wort; or by adding a little moist sugar or treacle to induce a fresh fermentation.

HEADING. This is added to thin and vapid beer to make it bear a frothy head. The most innocent, pleasant, and effective addition of this sort is a mixture of pure ammonio-citrate of iron and salt of tartar, about equal parts in the proportion of only a few grains to a quart.

IMPROVING. This is the trade synonym of ‘ADULTERATION’ and ‘DOCTORING,’ Nevertheless there are cases in which ‘improvement’ may be made without affecting the wholesome character of the liquor. Of this kind is the addition of hops, spices, &c., during the maturation of beer that exhibits a tendency to deteriorate. For this purpose some persons cut a half quartern loaf into slices, and after toasting them very high, place them in a coarse linen bag along with 1/2 lb. of hops, and 2 oz. each of bruised ginger, cloves, and mustard seed, and suspend the bag by means of a string a few inches below the surface of the beer (a hogshead), which is then bunged close. The addition of a little ground capsicum in the same way is also a real improvement to beer, when judiciously made.

MUSTINESS. To each hogshead, racked into clean casks, add 1 lb. of new hops boiled in a gallon of the liquor, along with 7 lbs. of newly-burnt charcoal (coarsely bruised, and the fine dust sifted off), and a 4-lb. loaf of bread cut into thin slices and toasted rather black; ‘rouse up’ well every day for a week, then stir in of moist sugar 3 or 4 lbs., and bung down for a fortnight.

RECOVERING. This is said of unsaleable beer when rendered saleable, by giving it ‘head’ or removing its ‘tartness.’

RIPENING. This term is applied to the regular maturation of beer. It is also used to express the means by which liquors already mature are rendered brisk, sparkling, or fit and agreeable for immediate use. In the language of the cellar, malt liquors are said to be ‘up’ when they are well charged with gaseous matter, and bear a frothy head. These qualities depend on the undecomposed sugar undergoing fermentation, which, when active, can only be of comparatively short duration, and should, therefore, be repressed rather than excited in beers not required for immediate consumption. When we desire to give ‘briskness’ to these liquors, whether in cask or bottle, it is only necessary to expose them for a few days to a slight elevation of temperature, by removing them, for instance, to a warmer apartment. This is the plan successfully adopted by bottlers. The addition of a small lump of white sugar to each bottle of ale or beer, or a teaspoonful of moist sugar to each bottle of porter, just before corking it, will render it fit for drinking in a few days in ordinary weather, and in 2 or 3 days in the heat of summer. A raisin or a lump of sugar candy is often added to each bottle with a like intention. The Parisians bottle their beer one day and sell it the next. For this purpose, in addition to the sugar as above, they add 2 or 3 drops of yeast. Such bottled liquor must, however, be drunk within a week, or else stored in a very cold place, as it will otherwise burst the bottles or blow out the corks.

ROPINESS. A little infusion of catechu or of oak bark, and some fresh hops, may be added to the beer, which in a fortnight should be rummaged well, and the next day ‘fined’ down.

SOURNESS. Powdered chalk, carbonate of soda, salt of tartar, or pearlash, is commonly added by the publicans to the beer, until the acidity is nearly removed, when 4 or 5 lbs. of moist sugar or foots per hogshead are ‘rummaged’ in, together with sufficient water to disburse double the amount of the outlay and trouble. Such beer must be soon put on draught, as it is very apt to get flat by keeping. Oyster shells and egg shells are also frequently used by brewers for the same purpose. To remove the acidity of beer, on the small scale, a few grains of carbonate of soda per glass may be added just before drinking it.

STORING. The situation of the beer-cellar should be such as to maintain its contents at a permanently uniform temperature, ranging between 44° and 50° Fahr., a condition which can only be ensured by choosing for its locality an underground apartment, or one in the centre of the basement portion of a large building.

VAMPING. Half fill casks with the old liquor, fill them up with some newly brewed, and bung close for 3 weeks or a month.

=MALTIN.= A nitrogenous ferment obtained from malt, which it is believed by Dubrunfaut to be the active principle, and is more energetic than diastase. The above chemist states it may be precipitated from extract of malt, by the addition of two molecules of alcohol at 90 per cent. According to Dubrunfaut maltin exists in all cereal grains, and in the water of rivers and brooks; but not in the well water of Paris.

=MALTING.= The method of converting barley, wheat, oats, or any other description of grain into malt. There are four successive stages in the process of malting, viz., steeping, couching, flooring, and kiln-drying.

1. _Steeping or moistening._——The grain is placed in a large wooden or stone cistern, and sufficient water run in to cover it. Here it remains for a period of from 40 to 60 hours, depending on the temperature of the weather, or until it becomes soft enough to be easily pierced with a needle, or crushed between the thumb and finger without yielding a milky juice. While in steep the grain swells, increasing nearly one fifth in bulk, and about 50 per cent. in weight. The water is then drained off, and the grain is ready for the next operation.

2. _Couching or germinating._——From the cistern the swollen barley is thrown out into the couch frame to the depth of from 14 or 20 inches, where heat is generated and germination induced. Here it is allowed to remain for from 20 to 30 hours, according to the state of the weather, until the acrospire or pumule shoots forth. Were the grain to remain long in the couch, particularly in warm weather, it would be either unduly forced or turn sour. Whilst in couch it rises in temperature about 15 degrees, and gives off some of its extra moisture. This is called sweating, and as the rootlets now begin to shoot out, means must be taken to check the germination.

3. _Flooring or regulating._——This consists in spreading the heated barley on the floor at different depths, according as it is required to increase or retard germination. During this stage of the operation the art of the maltster may be more properly said to commence, as now all his judgment is brought into requisition. The grain must be turned three or four times a day, and at each turning the layer is spread out more and more, until it is reduced to the depth of about three or four inches. The chief object to be attained by this operation is a regular germination of the grain.

4. _Kiln-drying._——The sprouted barley is next spread in a thin layer on the malt kiln, and heat applied. The temperature to which the kiln is raised varies according to the purpose for which the malt is required, the difference between pale, amber, and brown malt depending solely on the degree of heat to which each has been subjected, and the manner in which the heat has been applied (see MALT). If the malt were not kiln-dried it would not keep, but would become mouldy. By the process of drying, the vitality of the seed is destroyed, and it may then be preserved without suffering further change.

_Product._——Good barley yields about 80% by weight and 109% by measure, of dried and sifted malt. Of the loss by weight 12% must be referred to water existing in the raw grain.

=MAN′′GANESE.= Mn. _Syn._ MANGANESIUM, L. A hard, brittle metal, discovered by Gahn in the black oxide of manganese of commerce.

_Prep._ Reduce manganous carbonate to fine powder, make it into a paste with oil, adding about 1-10th of its weight of calcined borax, place the mixture in a Hessian crucible lined with charcoal, lute on the cover, and expose it to the strongest heat of a smith’s forge for 2 hours; when cold, break the crucible and preserve the metallic button in naphtha.

_Obs._ The product is probably a carbide of manganese, just as steel is a carbide of iron. Deville has lately prepared pure manganese by reducing the pure oxide by means of an insufficient quantity of sugar charcoal in a crucible made of caustic lime.

_Prop._ As prepared by Deville, metallic manganese has a reddish lustre, like bismuth; it is very hard and brittle; when powdered, it decomposes water, even at the lowest temperature. Dilute sulphuric acid dissolves it with great energy, evolving hydrogen. Sp. gr. 7·13. In an oxidised state manganese is abundant in the mineral kingdom, and traces of it have been found in the ashes of plants and in mineral waters.

The salts of manganese may be easily prepared in a state of purity by dissolving the precipitated carbonate in the acids. Most of them are soluble, and several are crystallisable.

_Tests._ Manganous salts are distinguished as follows:——The hydrates of potassium and sodium give white precipitates insoluble in excess, and rapidly turning brown. The presence of ammonium salts interferes with these tests. Ammonia gives similar results.

Ferrocyanide of potassium gives a white precipitate. Sulphuretted hydrogen gives no precipitate in acid solutions, and precipitates neutral solutions only imperfectly; but in alkaline solutions it gives a bright, flesh-coloured, insoluble precipitate, which becomes dark brown on exposure to the air. Sulphide of ammonium, in neutral solutions, also yields a similar precipitate, which is very characteristic. A compound of manganese fused with borax in the outer flame of the blowpipe gives a bead, which appears of a violet-red colour whilst hot, and upon cooling acquires an amethystine tint; this colour is lost by fusion in the inner flame. Heated upon platinum foil with a little carbonate of sodium, in the outer flame, it yields a green mass whilst hot, which becomes bluish green when cold.

=Manganous Ace′tate.= Mn(C_{2}H_{3}O_{2})_{2}. _Syn._ ACETATE OF PROTOXIDE OF MANGANESE; MANGANII ACETAS, L. _Prep._ 1. By neutralising concentrated acetic acid with manganous carbonate, and evaporating the solution so that crystals may form.

_Prop., &c._ The crystals, when pure, are of a pale red colour; permanent in the air; soluble in alcohol, and 3-1/2 parts of water, and possess an astringent and metallic taste.——_Dose_, 5 to 10 gr., as an alterative, hæmatinic, &c.

=Manganous Car′bonate.= MnCO_{3}. _Syn._ CARBONATE OF PROTOXIDE OF MANGANESE; MANGANESII CARBONAS, L. _Prep._ Reduce the black oxide of manganese of commerce to fine powder, and after washing it in water acidulated with hydrochloric acid, dissolve it in strong hydrochloric acid, and evaporate the resulting solution to dryness; dissolve the residue in water, and add to the solution sufficient sodium carbonate to precipitate all the iron present; digest the mixed precipitate in the remainder of the liquid, filter, add ammonium sulphide until it begins to produce a flesh-coloured precipitate, then filter, and add sodium carbonate as long as a precipitate falls; lastly, well wash the newly-formed carbonate in water, and dry it by a gentle heat.

2. By directly precipitating a solution of the chloride with sodium carbonate, and washing and drying the powder as before.

_Prop., &c._ A pale buff or cream-coloured powder; insoluble in water; freely soluble in acids; exposed to a strong heat, it loses its carbonic acid, absorbs oxygen, and is converted into the red oxide. It is chiefly employed in the preparation of the other salts of manganese.

=Manganous Chlo′′ride.= MnCl_{2}. _Syn._ PROTOCHLORIDE OF MANGANESE, MURIATE OF M.; MANGANESII CHLORIDUM, L. _Prep._ 1. By saturating hydrochloric acid with manganous carbonate; the solution is greatly concentrated by evaporation, when crystals may be obtained, or it is at once evaporated to dryness; in either case the product must be placed in warm, dry, stoppered bottles, and preserved from the air.

2. From the dark brown residual liquid of the process of obtaining chlorine from binoxide of manganese and hydrochloric acid; this liquid is evaporated to dryness, and then slowly heated to dull redness in an earthen vessel, with constant stirring, and kept at that temperature for a short time; the greyish-looking powder thus obtained is treated with water, and the solution separated from the ferric oxide and other insoluble matter by filtration; if any iron still remains, a little manganous carbonate is added, and the whole boiled for a few minutes; the filtered solution is then treated as before. This is the least expensive and most convenient source of this salt.

_Prop., &c._ Rose-coloured tabular crystals; inodorous; very soluble both in water and alcohol; very deliquescent; when gradually heated to fusion the whole of the water is expelled, and at a red heat it slowly suffers decomposition. Astringent, tonic, hæmatinic, and alterative.——_Dose_, 3 to 10 gr.; in scorbutic, syphilitic, and certain chronic cutaneous affections; anæmia, chlorosis, &c.

=Manganous Hydrate.= Mn(HO)_{2}. _Syn._ HYDRATED PROTOXIDE OF MANGANESE. _Prep._ Formed by adding potassium hydrate to manganous sulphate, and filtering and drying the precipitate in vacuo. White powder rapidly absorbing oxygen and burning first green and then brown from formation of higher oxides.

=Manganous I′odide.= MnI_{2}. _Syn._ MANGANESII IODIDUM, L. _Prep._ By dissolving the carbonate in hydriodic acid and evaporating the filtered liquid in vacuo or out of contact with air.——_Dose_, 1 to 3 gr.; in anæmia, chlorosis, &c., occurring in scrofulous subjects.

=Manganous Oxide.= MnO. _Syn._ PROTOXIDE OF MANGANESE. _Prep._ By passing a current of hydrogen over manganous carbonate heated to whiteness in a porcelain tube. Olive-green powder rapidly oxidising on exposure to air, and soluble in acids forming manganous salts.

There are four other oxides and two oxyhydrates that may be treated of here, but of which only the peroxide and the manganates and permanganates are of practical importance.

=Manganous-manganic Oxide.= Mn_{3}O_{4}, or MnO.Mn_{2}O_{3}. _Syn._ RED OXIDE OF MANGANESE, PROTOSESQUIOXIDE OF MANGANESE. Found native as “Hansmanite”. It is produced by igniting manganous carbonate, or manganic oxide, or manganic peroxide. Reddish-brown, coloured crystals or powder, and communicates an amethyst colour to glass when fused with it.

=Manganous-manganic Peroxide.= Mn_{4}O_{7} or MnO_{3}.Mn_{2}O_{3}. _Syn._ INTERMEDIATE, OXIDE OF MANGANESE. Found native as “Varvicile,” as a black hard crystalline mass. Decomposed when heated into a lower oxide and oxygen.

=Manganous Phosphate.= MnH.PO_{4} + 6Aq. _Syn._ PHOSPHATE OF PROTOXIDE OF MANGANESE; MANGANESII PHOSPHAS, L. _Prep._ By precipitating a solution of manganous sulphate with a solution of sodium phosphate. It must be preserved from the air.——_Dose_, 3 to 12 gr.; in anæmia, rickets, &c.

=Manganous Sul′phate.= MnSO_{4}. _Syn._ SULPHATE OF PROTOXIDE OF MANGANESE; MANGANESII SULPHAS, L. _Prep._ 1. By dissolving manganous carbonate in dilute sulphuric acid, and evaporating the filtered solution so that crystals may form, or at once gently evaporating it to dryness. Pure.