Metallic Sentence Examples

The water was cool and had a metallic taste.

Moonlight and darkness alike bent and danced around him, surrounding him in a hazy metallic shimmer.

Metallic cobalt may be obtained by reduction of the oxide or chloride in a current of hydrogen at a red heat, or by heating the oxalate, under a layer of powdered glass.

On heating in hydrogen, ammonia or carbon monoxide, or with carbon or sodium, it is reduced to the metallic state.

It reduces many metallic oxides, such as lead monoxide and cupric oxide, and decomposes water at a red heat.

The wait lasted less than an hour before Dean heard the metallic sound of a key in the lock.

She was coated in blood, the metallic scent heightening her blood lust.

The water was cold and had a metallic taste she liked.

It assumes a metallic lustre on burnishing or heating to redness.

The entire gift is sprinkled with sparkling metallic wedding confetti.

Since the time when the system first became prominent all switchboards have been arranged for metallic circuits.

Large as this progress was it would have been much greater if the Telephone Company had been granted adequate powers to put wires underground and thus instal a complete metallic circuit in place of the single wire, earthreturn, circuit which it was constrained to employ.

This is considerably in excess of the circulation, 40,404,000, fixed by royal decree of 1900; but the issue of additional notes was allowed, provided they were entirely covered by a metallic reserve, whereas up to the fixed limit a 40% reserve only was necessary.

It is readily oxidized by nitric acid, and when strongly heated_ in a current of hydrogen is reduced to the metallic condition.

The metallic derivatives (phenolates, phenates or carbolates) of the alkali metals are obtained by dissolving phenol in a solution of a caustic alkali, in the absence of air.

As a whole, the birds of Papua are remarkable for their brilliance of plumage, or their metallic colouring.

It sublimes in thin plates of a dark colour and metallic lustre, and is soluble in solutions of the caustic alkalis.

In combination the element chiefly occurs as metallic sulphides and sulphates.

It combines with many metals to form sulphides, and also decomposes many metallic salts with consequent production of sulphides, a property which renders it extremely useful in chemical analysis.

It is formed when sulphur is burned in air or in oxygen, or when many metallic sulphides are roasted.

It combines directly with chlorine to form sulphuryl chloride and also with many metallic peroxides, converting them into sulphates.

The pronotum and elytra are often adorned with bright colours or metallic lustre, and marked with stripes or spots.

Most of the Chrysomelidae are metallic in colour and convex in form; in some the head is concealed beneath the prothorax, and the so-called "tortoise" beetles (Cassidinae) have the elytra raised into a prominent median ridge.

The larvae of the beautiful, elongate, metallic Donaciae live in the roots and stems of aquatic plants, obtaining thence both food and air.

In Berlin, on the Stadtbahn - which for a part of its length traverses private property - masonry arches, or earthen embankments between retaining walls, were substituted for the metallic structure wherever possible.

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.

In the parish of Ludgvan were rich copper works, abounding with mineral and metallic fossils, of which he made a collection, and thus was led to study somewhat minutely the natural history of the county.

It is an ironblack, opaque mineral, with metallic lustre; hardness about 6, sp. gr.

The bit or cutter consists of a cylindrical The Calyx metallic shell, the lower end of which is made, by a Drill.

In instruments for larger currents the main current passes through a metallic strip acting as a bye-pass or shunt, and to the ends of this shunt are attached the ends of the working wire.

This he achieved by the introduction of a device which is called a metallic ligament.

In a scientific definition the compounds of fatty acids with basic metallic oxides, lime, magnesia, lead oxide, &c., should also be included under soap; but, as these compounds are insoluble in water, while the very essence of a soap in its industrial relations is solubility, it is better to speak of the insoluble compounds as " plasters, " limiting the name " soap " as the compounds of fatty acids with soda and potash.

The extent to which a soap is hydrolysed depends upon the acid and on the concentration of the solution; it is also affected by the presence of metallic salts, e.g.

The so-called " floating soaps " are soaps made lighter than water either by inserting cork or a metallic plate so as to form an air space within the tablet.

In 1808 Davy isolated sodium and potassium; he then turned his attention to the preparation of metallic calcium, barium, strontium and magnesium.

At the same time Berzelius obtained the element, in an impure condition, by fusing silica with charcoal and iron in a blast furnace; its preparation in a pure condition he first accomplished in 1823, when he invented the method of heating double potassium fluorides with metallic potassium.

Stromeyer detected a new metallic element, cadmium, in certain zinc ores; it was rediscovered at subsequent dates by other observers and its chemical resemblance to zinc noticed.

Organic Chemistry While inorganic chemistry was primarily developed through the study of minerals - a connexion still shown by the French appellation chimie minerale - organic chemistry owes its origin to the investigation of substances occurring in the vegetable and animal organisms. The quest of the alchemists for the philosopher's stone, and the almost general adherence of the iatrochemists to the study of the medicinal characters and preparation of metallic compounds, stultified in some measure the investigation of vegetable and animal products.

In fact, the analogy between the alkyl groups and metallic elements forms a convenient basis from which to consider many derivatives.

A metallic globule with or without an incrustation may be obtained.

Gold and copper salts give a metallic bead without an incrustation.

Any film formed in the first case is metallic, in the second it is the oxide.

The metallic film is tested with 20% nitric acid and with bleaching-powder solution.

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.

On the chromophoreauxochrome theory (the nitro group being the chromophore, and the hydroxyl the auxochrome) it is necessary in order to explain the high colour of the metallic salts and the colourless alkyl and aryl derivatives to assume that the auxochromic action of the hydroxyl group is only brought strongly into evidence by salt formation.

He has also shown that the nitrophenols yield, in addition to the colourless true nitrophenol ethers, an isomeric series of coloured unstable quinonoid aci-ethers, which have practically the same colour and yield the same absorption spectra as the coloured metallic salts.

The globe itself rotates within a metallic meridian to which its axis is attached.

In this emergency assignats were issued to provide a substitute for a metallic currency.

In 1790 the interest was reduced to 3%, and as the treasury had again become exhausted, a further issue was decided upon; it was also decreed that the assignats were to be accepted as legal tender, all public departments being instructed to receive them as the equivalent of metallic money.

The fish of Cuban waters are remarkable for their metallic colourings.

It converts many metallic oxides into mixtures of nitrates and nitrites, and attacks many metals, forming nitrates and being itself reduced to nitric oxide.

More particularly, chased and inlaid metallic wares, bez (thin cotton) and carpet - weaving receive government support.

Finally, usage of paper money was restricted to the capital only, and in 1842 this partial reform of the paper currency was followed by a reform of the metallic currency, in the shape of an issue of gold, silver and copper currency of good value.

Certain varieties, notably some from Russia, possess a beautiful metallic sheen, referable to the presence of either microscopic fissures or enclosures.

When two metallic conductors are placed in an electrolyte, a current will flow through a wire connecting them provided that a difference of any kind exists between the two conductors in the nature either of the metals or of the portions of the electrolyte which surround them.

In other cases the injurious effects of free sulphur are obviated by using instead of it a metallic sulphide, - generally the orange sulphide of antimony; but, for the best results, it is necessary that this should contain from 20 to 30% of uncombined sulphur.

In the article Electrolysis it is shown how the passage of an electric current through a solution containing metallic ions involves the deposition of the metal on the cathode.

Large metallic surfaces (especially external surfaces) are sometimes plated by means of a "doctor," which, in its simplest form, is a brush constantly wetted with the electrolyte, with a wire anode buried amid the hairs or bristles; this brush is painted slowly over the surface of the metal to be coated, which must be connected to the negative terminal of the electrical generator.

In Carinthia the oxidizing process from the first is pushed on so far that metallic lead begins to show, and the oxygen introduced predominates over the sulphur left.

While he also prevents interruption of the operation by means of water-jackets, he uses hot-blast, and produces, besides metallic lead, large volumes of lead fumes which are drawn off by fans through long cooling tubes, and then forced through suspended bags which filter off the dust, called "blue powder."

Ores are smelted raw if the fall of matte (metallic sulphide) does not exceed 5%; otherwise they are subjected to a preliminary oxidizing roast to expel the sulphur, unless they run too high in silver, say 100 oz.

While the furnace is running the crucible and channel remain filled with lead; all the lead reduced to the metallic state in smelting collects in the crucible, and rising in the channel, overflows into the basin, whence it is removed.

In making up a charge, the ores and fluxes, whose chemical compositions have been determined, are mixed so as to form out of the components, not to be reduced to the metallic or sulphide state, typical slags (silicates of ferrous and calcium oxides, incidentally of aluminium oxide, which have been found to do successful work).

Formerly all argentiferous lead had to be cupelled, and the resulting litharge then reduced to metallic lead.

The distillation of 1000 lb charge lasts 5-6 hours, requires 500-600 lb coke or 30 gallons reduced oil, and yields about to% metallic zinc and I% blue powder - a mixture of finely-divided metallic zinc and zinc oxide.

Lead generally functions as a divalent element of distinctly metallic character, yielding a definite series of salts derived from the oxide PbO.

It ignites when heated in air with the formation of the monoxide; dilute acids convert it into metallic lead and lead monoxide, the latter dissolving in the acid.

Here compounds of divalent lead have not yet been obtained; by acting with zinc ethide on lead chloride, lead tetraethide, Pb(C 2 IH Q) 4, is obtained, with the separation of metallic lead.

Vulcanized rubber overshoes were first made in Naugatuck, and in 1843 the Goodyear's Metallic Rubber Shoe Company was established here.

They act as reducing agents, silver nitrate in the presence of ammonia being rapidly reduced to the condition of metallic silver.

In 1855, ignorant of what Wailer had done ten years previously, he succeeded in obtaining metallic aluminium, and ultimately he devised a method by which the metal could be prepared on a large scale by the aid of sodium, the manufacture of which he also developed.

Columbium hydride, CbH, is obtained as a greyish metallic powder, when the double fluoride, CbF 5, 2 KF, is reduced with sodium.

It forms many double salts with other metallic fluorides.

Metallic money is limited to nickel and bronze coins, but in 1906 the government was authorized to purchase bar silver for the coinage of pieces of the denomination of two milreis, one milreis and 500 reis (2-milreis).

The works by his hand are remarkable for their ruby tint, with a beautiful metallic lustre; but only one small tazza remains in Gubbio itself.

In his experiments upon this subject Fraunhofer employed plates of glass dusted over with lycopodium, or studded with small metallic disks of uniform size; and he found that the diameters of the rings were proportional to the length of the waves and inversely as the diameter of the disks.

The metallic plate thus produced formed, when stripped from its support, a reflection grating reproducing many of the characteristics of the original.

By reducing the oxide with charcoal at a high temperature, he obtained a product which he took to be metallic uranium.

Metallic uranium, as shown by Peligot, can be obtained by the reduction of a mixture of dry chloride of potassium and dry uranous chloride, UC1 4, with sodium at a red heat.

It forms double salts with metallic chlorides and with the hydrochlorides of organic bases.

Being a component of bronze, it was used as a metal thousands of years prior to the dawn of history; but it does not follow that prehistoric bronzes were made from metallic tin.

Grains of metallic tin occur intermingled with the gold ores of Siberia, Guiana and Bolivia, and in a few other localities.

The first stage has for its purpose the production of a fairly pure tinstone; the second the conversion of the oxide into metallic tin; and the third preparing a tin pure enough for commercial purposes.

The alluvial extracted, which in the Malay Peninsula and Archipelago carries from 5 to 60 lb of tinstone (or "black tin," as it is termed by Cornish miners) to the cubic yard of gravel, is washed in various simple sluicing appliances, by which the lighter clay, sand and stones are removed and tinstone is left behind comparatively pure, containing usually 65 to 75% of metallic tin (chemically pure tinstone contains 78.7%).

The Bolivian tin ore is treated by first extracting the silver by amalgamation, &c., and afterwards concentrating the residues; there are, however, considerable difficulties in the way of treating the poorer of these very complex ores, and several chemical processes for extracting their metallic contents have been worked out.

The sal-ammoniac removes the last unavoidable film of oxide, leaving a purely metallic surface, to .which the tin adheres firmly.

One part of cream of tartar, two of alum and two of common salt are dissolved in boiling water, and the solution is boiled with granulated metallic tin (or, better, mixed with a little stannous chloride) to produce a tin solution; and into this the articles are put at a boiling heat.

In the absence of metallic tin there is no visible change; but, as soon as the metal is introduced, an electrolytic action sets in and the articles get coated over with a firmly adhering film of tin.

A strip of metallic zinc when placed in a solution of stannous chloride precipitates the tin in crystals and takes its place in the solution.

Stannic sulphide, SnS 2, is obtained by heating a mixture of tin (or, better, tin amalgam), sulphur and sal-ammoniac in proper proportions in the beautiful form of aurum musivum (mosaic gold) - a solid consisting of golden yellow, metallic lustrous scales, and used chiefly as a yellow "bronze" for plaster-of-Paris statuettes, &c. The yellow precipitate of stannic sulphide obtained by adding sulphuretted hydrogen to a stannic solution readily dissolves in solutions of the alkaline sulphides to form thiostannates of the formula M 2 SnS 31 the free acid, H2SnS3, may be obtained as an almost black powder by drying the yellow precipitate formed when hydrochloric acid is added to a solution of a thiostannate.

It forms crystalline compounds with bromine and with many metallic salts.

Certain metallic poisons give rise to pigmentation of the tissues, e.g.

It was based on an accidental observation of the action of metallic aluminium on amyl chloride, and consists in bringing together a hydrocarbon and an organic chloride in presence of aluminium chloride, when the residues of the two compounds unite to form a more complex body.

They pass through a viscous stage in cooling from a state of fluidity; they develop effects of colour when the glass mixtures are fused with certain metallic oxides; they are, when cold, bad conductors both of electricity and heat, they are easily fractured by a blow or shock and show a conchoidal fracture; they are but slightly affected by ordinary solvents, but are readily attacked by hydrofluoric acid.

The theory most widely accepted at present is that glass is a quickly solidified solution, in which silica, silicates, borates, phosphates and aluminates may be either solvents or solutes, and metallic oxides and metals may be held either in solution or in suspension.

The colouring agents are generally metallic oxides.

A similar glass, if its cooling is greatly retarded, produces throughout its substance minute crystals of metallic copper, and closely resembles the mineral called avanturine.

The surface of vessels may be spangled with gold or platinum by rolling the hot glass on metallic leaf, or iridescent, by the deposition of metallic tin, or by the corrosion caused by the chemical action of acid fumes.

The process consisted in spreading the leaf on a thin film of blown glass and pressing molten glass on to the leaf so that the molten glass cohered with the film of glass through the pores of the metallic leaf.

If before this application of the molten glass the metallic leaf, whilst resting on the thin film of blown glass, was etched with a sharp point, patterns, emblems, inscriptions and pictures could be embedded and rendered permanent by the double coating of glass.

The principle of applying metallic films to glass seems to have been known to the Romans and even to the Egyptians, and is mentioned by Alexander Neckam in the 12th century, but it would appear that it was not until the 16th century that the process of " silvering " mirrors by the use of an amalgam of tin and mercury had been perfected.

It combines directly with ammonia to form the compound SiF 4 2NH,, and is absorbed by dry boric acid and by many metallic oxides.

When heated with the alkali and alkaline earth metals it yields silicon and the corresponding metallic chlorides.

The progress of science has, in fact, been accompanied by the discovery of some 70 elements, which may be arranged in order of their "metallic" properties as above indicated, and it is found that while the end members of the scale are most distinctly metallic (or non-metallic), certain central members, e.g.

They are (at least practically) non-transparent; they reflect light in a peculiar manner, producing what is called "metallic lustre."

Metallic Substances Produced by the Union of Metals with Small Proportions of Non-Metallic Elements.

Of the heavy metals, copper is the one which exhibits by far the greatest avidity for sulphur, its subsulphide Cu 2 S being the stablest of all heavy metallic sulphides in opposition to dry reactions.

Metallic chlorides, as a class, are readily soluble in water.

It resembles acetylene in yielding metallic derivatives with ammoniacal copper and silver solutions.

Stahl, as late as 1702, quoted the formation of brass as a case of the union of a metal with an earth into a metallic compound; but he subsequently adopted the view propounded by Kunckel in 1677, that "cadmia" is a metallic calx, and that it dyes the copper yellow by giving its metal up to it.

Oxide of zinc, like most heavy metallic oxides, is easily reduced to the metallic state by heating it to redness with charcoal; pure red zinc ore may be treated directly; and the same might be done with pure calamine of any kind, because the carbon dioxide of the zinc carbonate goes off below redness and the silica of zinc silicate only retards, but does not prevent, the reducing action of the charcoal.

In practice, however, we never have to deal with pure zinc minerals, but with complex mixtures, which must first of all be subjected to mechanical operations, to remove at least part of the gangue, and if possible also of the heavy metallic impurities.

It is also manufactured by the latter process from the metallic zinc liquated out of galvanizer's dross.

Moissan showed that at this temperature the most stable of mineral combinations are dissociated, and the most refractory elements are converted into vapour, only certain borides, silicides and metallic carbides having been found to resist the action of the heat.

Ordinarily carbon is used as the electrode material, but when carbon comes in contact at high temperatures with any metal that is capable of forming a carbide a certain amount of combination between them is inevitable, and the carbon thus introduced impairs the mechanical properties of the ultimate metallic product.

Alumina and lime, for example, which cannot be reduced at ordinary furnace temperatures, readily give up their oxygen to carbon in the electric furnace, and then combine with an excess of carbon to form metallic carbides.

The isolation of metallic titanium is very difficult since it readily combines with nitrogen (thus resembling boron and magnesium) and carbon.

In 1822 Wollaston examined a specimen of those beautiful copper-like crystals which are occasionally met with in iron-furnace slags, and declared them to be metallic titanium.

The tetraiodide, TiI 4, is a reddish brown mass having a metallic lustre.

It precipitates many metallic hydroxides.

It combines directly with many metallic salts.

His voice is musical, metallic, fit for loud laughter and piercing wail, and all that may lie between; speech and speculation free and plenteous; I do not meet in these late decades such company over a pipe."

The frec end of the hilt was crowned with a metallic cap or pommel (kashira), the other extremity next the tsuba was embraced by an oval ring (fuchi), and in the middle was affixed on each side a special ornament called the menuki, all adapted in material and workmanship to harmonize with the guard.

The metallic bowl and mouthpiece of the pipe offered a tempting surface for embellishment, as well as the clasp of the pouch; and the netsuke, being made of wood, ivory or other material susceptible of carving, also gave occasion for art and ingenuity.

The engravers of pipes, pouch clasps, and the metallic discs (kagami-buta) attached to certain netsuke, sprang from the same class and were not less original.

It consists of a stoneware tank with a thin sheet of platinum-iridium alloy at either end forming the primary electrodes, and between them a number of glass plates reaching nearly to the bottom, each having a platinum gauze sheet on either side; the two sheets belonging to each plate are in metallic connexion, but insulated from all the others, and form intermediary or bi-polar electrodes.

Depending on the fact that the electrical conductivity of a metallic conductor is decreased by heat, it consists of two strips of platinum, arranged to form the two arms of a Wheatstone bridge; one strip being exposed to a source of radiation from which the other is shielded, the heat causes a change in the resistance of one arm, the balance of the bridge is destroyed, and a deflection is marked on the galvanometer.

This view, which was specially supported by Gay-Lussac and Leopold Gmelin and accepted by Berzelius, necessitated that all acids were monobasic. The untenability of this theory was proved by Thomas Graham's investigation of the phosphoric acids; for he then showed that the ortho- (ordinary), pyroand metaphosphoric acids contained respectively 3, 2 and I molecules of " basic water " (which were replaceable by metallic oxides) and one molecule of phosphoric oxide, P2 05.

Graham's work was developed by Liebig, who called into service many organic acids - citric, tartaric, cyanuric, comenic and meconic - and showed that these resembled phosphoric acid; and he established as the criterion of polybasicity the existence of compound salts with different metallic oxides.

The substances which we at present term anhydrous acids (acid oxides) only become, for the most part, capable of forming salts with metallic oxides after the addition of water, or they are compounds which decompose these oxides at somewhat high temperatures."

It is apparent that metallic salts of organic acids would, in aqueous solution, be ionized, the positive ion being the metal, and the negative ion the acid residue.

In what follows we shall confine our attention principally to metallic alloys.

When a solution of silver nitrate is poured on to metallic mercury, the mercury replaces the silver in the solution, forming nitrate of mercury, and the silver is precipitated; it does not, however, appear as pure metallic silver, but in the form of crystalline needles of an alloy of silver and mercury.

In the case of this pair of metals, or indeed of any metallic alloy, we cannot see the crystals forming, nor can we easily filter them off and examine them apart from the liquid, although this has been done in a few cases.

A group of bodies may, however, be yet discovered between alloys and electrolytes in which evidence may be found of some gradual change from wholly metallic to electrolytic conduction.

It dissolves most organic compounds, resins, hydrocarbons, fatty acids and many metallic salts, sometimes forming, in the latter case, crystalline compounds in which the ethyl alcohol plays a role similar to that of water of crystallization.

Thorpe and Laurie converted potassium auribromide into a mixture of metallic gold and potassium bromide by careful heating.

Gold is found in nature chiefly in the metallic state, i.e.

One of the greatest difficulties in the treatment of gold by amalgamation, and more particularly in the treatment of pyrites, arises from the so-called " sickening " or " flouring " of the mercury; that is, the particles, losing their bright metallic surfaces, are no longer capable of coalescing with or taking up other metals.

The auric chloride is, however, decomposed at the elevated temperature into finely divided metallic gold, which is then readily attacked by the chlorine gas.

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.

The Carpathian system is richer in metallic ores than any other mountain system of Europe, and contains large quantities of gold, silver, copper, iron, lead, coal, petroleum, salt, zinc, &c., besides a great variety of useful mineral.

When not tarnished, the mineral has a silver-white colour with a tinge of red, and the lustre is metallic. Hardness 2-21; specific gravity 9-70-9.83.

The extraction from ores in which the bismuth is present in the metallic condition may be accomplished by a simple liquation, or melting, in which the temperature is just sufficient to melt the bismuth, or by a complete fusion of the ore.

Sulphuretted ores are smelted, either with or without a preliminary calcination, with metallic iron; calcined ores may be smelted with carbon (coal).

The lowest layer of the molten mass is principally metallic bismuth, the succeeding layers are a bismuth copper matte, which is subsequently worked up, and a slag.

The solution of metallic chlorides or sulphates so obtained is precipitated by iron, the metallic bismuth filtered, washed with water, pressed in canvas bags, and finally fused in graphite crucibles, the surface being protected by a layer of charcoal.

Water decomposes it to metallic bismuth and the oxychloride, BiOC1.

Bismuth disulphide is a grey metallic substance, which is decomposed by hydrochloric acid with the separation of metallic bismuth and the formation of bismuth trichloride.

In quantitative estimations it is generally weighed as oxide, after precipitation as sulphide or carbonate, or in the metallic form, reduced as above.

Hull; some months earlier Lebedew had published in the Annalen der Physik a verification for metallic vanes so thin as to avoid the gasaction, by preventing the production of sensible difference of temperature between the two faces by the incident radiation.

Other methods are to place the metal and mercury together in dilute acid, to add mercury to the solution of a metallic salt, to place a metal in a solution of mercuric nitrate, or to electrolyse a metallic salt using mercury as the negative electrode.

These insects are adorned with bands of black and yellow, or with bright metallic colours, and on account of their large size and formidable ovipositors they often cause needless alarm to persons unfamiliar with their habits.

The vast majority of this group, including nearly 5000 known species, are usually reckoned as a single family, the Chalcididae, comprising small insects, often of bright metallic colours, whose larvae are parasitic in insects of various orders.

The Pentatomidae (shield bugs), some of which are metallic or otherwise brightly coloured, are easily recognized by the great development of the scutellum, which reaches at least half-way back towards the tip of the abdomen, and in some genera covers the whole of the hind body, and also the wings when these are closed.

It is best obtained by decomposing metallic tellurides with mineral acids.

Hackspill (Comptes Rendus, 5905, 141, p. 101) finds that metallic caesium can be obtained more readily by heating the chloride with metallic calcium.

It combines with many metallic sulphates (silver, zinc, cobalt, nickel, &c.) to form double sulphates of the type Cs2S04 RS04.6H20.

The formation of hydrogen is caused by small traces of metallic calcium occasionally found free in the carbide, and cases have been known where this was present in such quantities that the evolved gas contained nearly 20% of hydrogen.

This takes place when in the manufacture of the carbide the material is kept too long in contact with the arc, since this overheating causes the dissociation of some of the calcium carbide and the solution of metallic calcium in the remainder.

The colour of the mineral is silver-white or steel-grey, with a metallic lustre, but it is often tarnished yellow; the streak is greyish-black.

Though part of the plumage in many sun-birds gleams with metallic lustre, they owe much of their beauty to feathers which are not lustrous, though almost as vivid,' and the most wonderful combination of the brightest colours - scarlet, purple, blue, green and yellow - is often seen in one and the same bird.

They are crystalline solids showing a characteristic green metallic lustre; they are readily soluble in water and dye red or violet.

The metal was obtained by Berzelius as an iron-grey powder by heating potassium zirconofluoride with metallic potassium.

The lustre is metallic and brilliant.

The earliest metallic money did not consist of coins, but of unminted metal in the form of rings and other ornaments or of weapons, which were used for thousands of years by the Egyptian, Chaldean and Assyrian Empires.

This is removed by solution in hot dilute sulphuric acid and a layer of pure frosted silver is left on the surface, which appears dead white in colour, and has lost its metallic lustre.

For instance, a ticking watch may be put at the focus of a large concave metallic mirror, which sends a parallel " beam " of sound to a second concave mirror facing the first.

Beneath the lower or fixed plate are four metallic rings furnished with holes corresponding to those in the plates, and which may be pushed round by projecting pins, so as to admit the air-current through any one or more of the series of perforations in the fixed plate.

The present article relates chiefly to metallic bridges.

His attempts at isolating this metal were not completely successful; in fact, metallic calcium remained a laboratory curiosity until the beginning of the 10th century.

Davy, inspired by his successful isolation of the metals sodium and potassium by the electrolysis of their hydrates, attempted to decompose a mixture of lime and mercuric oxide by the electric current; an amalgam of calcium was obtained, but the separation of the mercury was so difficult that even Davy himself was not sure as to whether he had obtained pure metallic calcium.

On electrolysis a layer of metallic calcium is formed at the lower end of this rod on the surface of the electrolyte; the rod is gradually raised, the thickness of the layer increases, and ultimately a rod of metallic calcium, forming, as it were, a continuation of the iron cathode, is obtained.

Ammonia gas has the power of combining with many substances, particularly with metallic halides; thus with calcium chloride it forms the compound CaCl 2.8NH 3, and consequently calcium chloride cannot be used for drying the gas.

A characteristic property of the alkaline fluorides is their power of combining with a molecule of hydrofluoric acid and with the fluorides of the more electro-negative elements to form double fluorides, a behaviour not shown by other metallic halides.

Metallic sodium possesses a silvery lustre, but on exposure to moist air the surface is rapidly dulled by a layer of the hydroxide.

The lustre is bright and metallic. In its external characters graphite is thus strikingly similar to molybdenite.

The graphite veins in the older crystalline rocks are probably akin to metalliferous veins and the material derived from deep-seated sources; the decomposition of metallic carbides by water and the reduction of hydrocarbon vapours have been suggested as possible modes of origin.

It may be prepared by passing carbon dioxide over red-hot carbon, or red-hot iron; by heating carbonates (magnesite, chalk, &c.) with zinc dust or iron; or by heating many metallic oxides with carbon.

On the 25th of April 1900 a law was enacted for the regulation of the constitution, capital, note emission and metallic reserves of banks.

These note issues are everywhere current at full nominal value, being secured under the provisions of the national banking law of 1896 by metallic reserves.

An important character, and one by which the mineral may always be recognized, is the perfect cubical cleavage, on which the lustre is brilliant and metallic. The colour of the mineral and of its streak is lead-grey; it is opaque; the hardness is 2 2 and the specific gravity 7.5.

Iodine is a greyish-black shining solid, possessing a metallic lustre and having somewhat the appearance of graphite.

The iodides can be prepared either by direct union of iodine with a metal, from hydriodic acid and a metal, oxide, hydroxide or carbonate, or by action of iodine on some metallic hydroxides or carbonates (such as those of potassium, sodium, barium, &c.; other products, however, are formed at the same time).

Silver iodide, mercurous iodide, and mercuric iodide are insoluble in water; lead iodide is sparingly soluble, whilst most of the other metallic iodides are soluble.

They are more easily reduced than the corresponding chlorates; an aqueous solution of hydriodic acid giving free iodine and a metallic oxide, whilst aqueous hydrochloric acid gives iodine trichloride, chlorine, water and a chloride.

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.

It is distinguished from the other members of the series by certain characteristic properties; for example, it shows an aldehydic character in reducing silver salts to metallic silver, and it does not form an acid chloride or an acid anhydride.

At this time the copper mines of Lake Superior were being successfully developed, and nearly 6oo tons of metallic copper were produced in 1850.

The grade of precious ores hafidled has generally and greatly decreased in recent yearsaccording to the census data of 1880 and 1902, disregarding all base metallic contentsfrom an average commerical value of $29.07 to one of $8.29; nevertheless the product of gold and silver has greatly increased.

The average percentage of metallic recovery from lead ores was about 68%, in 1880, and again in 1902, according to the national censuses of these years.

Of these the "acoucryptophone" was one of the most elegant - a light box, shaped like an ancient lyre and suspended by a metallic wire from a piano in the room above.

Goldschmidt (Annalen, 1898, 301, p. 19) in which the oxide is reduced by metallic aluminium; and if care is taken to have excess of the sesquioxide of chromium present, the metal is obtained quite free from aluminium.

Both in the gum and in the boiled-off state silk has the peculiar property of imbibing certain metallic salts largely and combining very firmly with them, the fibre remaining to external appearance undiminished in strength and lustre, but much added to in size and weight.

The metals may be introduced into the arc in various ways, and in some cases where they can be obtained in sufficient quantity the metallic electrodes may be used in the place of carbon poles.

An important experiment by C. Gunther 2 seems however to show that the radiation of metallic salts in a flame has an intensity equal to that belonging to it in virtue of its temperature.

In the case of other metallic groups similar series have also been found, but while in the case of the alkali group nearly the whole spectrum is represented by the combined set of three series, such is not the case with other metals.

The question is complicated by the fact that in the cases which have been observed, the greater portion of the metallic vapour vibrates in an atmosphere of similar molecules, and the static energy of the field is determined by the value of K applicable to the particular frequency.

The explanation of these facts presents no difficulty, inasmuch as during the sudden discharge which takes place in the absence of a self-induction, the metallic molecules have not sufficient time to diffuse through the spark gap; hence the discharge is carried by the gas in which it takes place.

Hemsalech 1 have measured the velocity with which the luminous molecules are projected from metallic poles when a strong spark is passed through the air interval which separates the poles.

It was found that during the successive electrical oscillations the metallic lines can be observed to stretch farther and farther away from the poles, thus giving a measure of the gradual diffusion of the metal.

While some of the phenomena seem to indicate that the projection of metallic vapours into the centre of the spark is a process of molecular diffusion independent of the mechanism of the discharge, the different velocities obtained with bismuth, and the probability that the vibrating systems are not electrically neutral, seem to indicate that the projected metallic particles are electrified and play some part in the discharge.

Pringsheim, who, by a series of experiments of undoubted merit, tried to establish that the emission of the line spectra of the alkali metals was invariably associated with a reduction of the metallic oxide.

In the light of our present knowledge we should look for the different behaviour in the peculiarity of the oxygen flame to ionize the metallic vapour.

It may also be prepared by heating a mixture of carbon, oxide of iron and magnesite to bright redness; and by heating a mixture of magnesium ferrocyanide and sodium carbonate, the double cyanide formed being then decomposed by heating it with metallic zinc. Electrolytic methods have entirely superseded the older methods.

The metallic borates are generally obtained in the hydrated condition, and with the exception of those of the alkali metals, are insoluble in water.

For this reason some observers use a thin strip of phosphor bronze to suspend the magnet, considering that the absence of a variable torsion more than compensates for the increased difficulty in handling the more fragile metallic suspension.

Experiments on alloys are, in some ways, easier to make than on pairs of non-metallic substances, partly owing to the possibility of polishing sections for microscopic examination, and the investigation of alloys has done much to elucidate the general phenomena of solution, of which metallic solution constitutes a special case.

One class, represented by gelatin, will redissolve on warming or diluting, while the other class, containing such substances as silica, albumen, and metallic, hydrosulphides, will solidify on heating or on the addition of electrolytes to form a solid "gel" which cannot be redissolved.

A beautiful thin faience with remarkable metallic glazes is made here.

The other breed, called the Cambridge, is much more variegated in colour, and some parts of the plumage have a bright metallic gloss, while the chicks are generally mottled with brownish grey.

This has been much crossed with the American Bronze, the largest of all, which has the beautiful metallic plumage of the wild bird, with the 1 The French Coq and Poule d'Inde (whence Dindon) involve no contradiction, looking to the general idea of what India then was.

Wdhler repeated the experiment at Göttingen in 1827, employing potassium alone as the reducing agent, he obtained it in the metallic state for the first time.

Contaminated as it was with potassium and with platinum from the crucible, the metal formed a grey powder and was far from pure; but in 1845 he improved his process and succeeded in producing metallic globules wherewith he examined its chief properties, and prepared several compounds hitherto unknown.

Before the application of electricity, only two compounds were found suitable for reduction to the metallic state.

It consisted simply in reducing cryolite with metallic sodium exactly as in Deville's chloride method, and it was claimed to possess various mythical advantages over its rival.

At elevated temperatures the metal decomposes nearly all other metallic oxides, wherefore it is most serviceable as a metallurgical reagent.

When there is an injurious preponderance of metallic oxides or other deleterious substances, the roots of trees would be affected by them, and they must therefore be removed.

In their simplest form, they are merely a row of slender stakes of larch or other wood driven into the ground, and connected by a slight rod or fillet at top. The use of iron rails has now been almost wholly discontinued on account of metallic substances acting as powerful conductors of both heat and cold in equal extremes.

With this object in view, the early improvers of hot-house architecture substituted metal for wood in the construction of the roofs, and for the most part dispensed with back walls; but the conducting power of the metal caused a great irregularity of temperature, which it was found difficult to control; and, notwithstanding the elegance of metallic houses, this circumstance, together with their greater cost, has induced most recent authorities to give the preference to wood.

For permanent plants, as trees, roses, &c., metallic labels with raised type are procurable from dealers, and are neat, durable and convenient.

Tudsbury that if an influence machine is enclosed in a metallic chamber containing compressed air, or better, carbon dioxide, the insulating properties of compressed gases enable a greatly improved effect to be obtained owing to the diminution of the leakage across the plates and from the supports.

In 1827 he obtained metallic aluminium as a fine powder, and in 1845 improved methods enabled him to get it in fully metallic globules.

By the same method as had succeeded with aluminium (reduction of the chloride by potassium) Wohler in 1828 obtained metallic beryllium and yttrium.

The iron oxide of which the ores of iron consist would be so easily deoxidized and thus brought to the metallic state by the carbon, i.e.

These are cementite, a definite iron carbide, Fe 3 C, harder than glass and nearly as brittle, but probably very strong under gradually and axially applied stress; and ferrite, pure or nearly pure metallic a-iron, soft, weak, with high electric conductivity, and in general like copper except in colour.

The desulphurizing effect of this transfer of the sulphur from union with iron to union with calcium is due to the fact that, whereas iron sulphide dissolves readily in the molten metallic iron, calcium;sulphide, in the presence of a slag rich in lime, does not, but by preference enters the slag, which may thus absorb even as much as 3% of sulphur.

Below this level the solid charge descends easily, because it consists of coke alone or nearly alone, and this in turn because the temperature here is so high as to melt not only the iron now deoxidized and brought to the metallic state, but also the gangue of the ore and the limestone, which here unite to form the molten slag, and run freely down between the lumps of coke.

Indeed, no limit has yet been found to the temperature which can be reached, if matters are so arranged that not only the carbon and silicon of the pig iron, but also a considerable part of the metallic iron which is the iron itself, are oxidized by the blast; or if, as in the Walrand-Legenisel modification, after the combustion of the initial carbon and silicon of the pig iron has already raised the charge to a very high temperature, a still further rise of temperature is brought about by adding more silicon in the form of ferro-silicon, and oxidizing it by further blowing.

It is in large part because of this shallowness, which contrasts so strongly with the height and roominess of the Bessemer converter, that the process lasts hours where the Bessemer process lasts minutes, though there is the further difference that in the open-hearth process the transfer of heat from flame to charge through the intervening layer of slag is necessarily slow, whereas in the Bessemer process the heat, generated as it is in and by the metallic bath itself, raises the temperature very rapidly.

The two metallic masses coalesce, and the reaction between the oxygen of one and the carbon of the other is therefore extremely rapid because it occurs throughout their depth, whereas in common procedure oxidation occurs only at the upper surface of the bath of cast iron at its contact with the overlying slag.

If this carbon is all present as graphite, so that in cooling the graphite-austenite diagram has been followed strictly (§ 26), the constitution is extremely simple; clearly the mass consists first of a metallic matrix, the carbonless iron itself with whatever silicon, manganese, phosphorus and sulphur happen to be present, in short an impure ferrite, encased in which as a wholly distinct foreign body is the graphite.

We must grasp clearly this conception of metallic matrix and encased graphite skeleton if we are to understand this subject.

The mass as a whole, then, consists of 96.4 parts of metallic matrix, which itself is in effect a 0.415% carbon rail steel, weakened and embrittled by having its continuity broken up by this skeleton of graphite forming 3.6% of the whole mass by weight, or say 12% by volume.

As, in succeeding members of this same series of cast irons, more of the graphite of the initial skeleton changes into cementite and thereby becomes part of the metallic matrix, so the graphite skeleton becomes progressively thinner and more discontinuous, and the matrix richer in cementite and hence in carbon and hence equivalent first to higher and higher carbon steel, such as tool steel of I carbon, file steel of 1.50%, wire-die steel of 2% carbon and then to white cast iron, which consists essentially of much cementite with little ferrite.

Here let us recognize that what gives this transfer of carbon from graphite skeleton to metallic matrix such very great influence on the properties of the metal is the fact that the transfer of each 1%.

First, if the skeleton which it forms is continuous, then its planes of junction with the metallic matrix offer a path of low resistance to the passage of liquids or gases, or in short they make the metal so porous as to unfit it for objects like the cylinders of hydraulic presses, which ought to be gas-tight and water-tight.

They seem also never to walk or run when on the ground, but always to hop. The bodyfeathers are commonly loose and soft; and, gaily coloured as are most of the species, in few of them has the plumage the metallic glossiness it generally presents in the pies, while the proverbial beauty of the "jay's wing" is due to the vivid tints of blue - turquoise and cobalt, heightened by bars of jet-black, an indication of the same style of ornament being observable in the greater FIG.

This salt is a colourless crystalline substance of composition CH30 C6H4 N2 CN HCN 2H20, and has the properties of a metallic salt; it is very soluble in water and its solution is an electrolyte, whereas the solutions of the synand anticompounds are not electrolytes.

The Chinese prepare a rouge, said to be from safflower, which, spread on the cards on which it is sold, has a brilliant metallic green lustre, but when moistened and applied to the skin assumes a delicate carmine tint.

It may be prepared by the electrolysis of acidulated water, by the decomposition of water by various metals or metallic hydrides, and by the action of many metals on acids or on bases.

Borax is very frequently employed; it melts to a clear liquid and dissolves silica and many metallic oxides.

Litharge and red lead are used in silver and gold assays, acting as solvents for silica and any metallic oxides present.

This connexion of isomerism with resistant linking, and of this with high valency, explains, in considerable measure, why inorganic compounds afforded, as a rule, no phenomena of this kind until the systematic investigation of metallic compounds by Werner brought to light many instances of isomerism in inorganic compounds.

The largest iron and steel works are at Essen, Oberhausen, Duisburg, Dusseldorf and Cologne, while cutlery and other small metallic wares are extensively made at Solingen, Remscheid and Aix-la-Chapelle.

It is therefore more probably due to metallic oxides than to hydrocarbons.

At the large and important Premier mine in the Transvaal the Elmore process, used in British Columbia and in Wales for the separation of metallic ores, has been also introduced.

Other authors have sought the origin of the diamond in the action of the hydrated magnesian silicates on hydrocarbons derived from bituminous schists, or in the decomposition of metallic carbides.

Weber's hypothesis of electric atoms, capable of diffusing through metallic bodies and conductors of electricity, but capable of vibration only in non-conductors, it is possible that the ultimate mechanism of conduction may be reduced in all cases to that of diffusion in metallic bodies or internal radiation in dielectrics.

A number of metallic points, supported on insulators, were connected by wires enclosing several hundred square metres on the top of a hill.

The white and calcined bones were then picked out of the ashes by the friends and placed in a metallic urn, which was deposited in a hollow grave or cist and covered over with large well-fitting stones.

From the filtered solution the thallium is recovered, as such, by means of pure metallic zinc, or by electrolysis.

The (approximately pure) metallic sponge obtained is washed, made compact by compression, fused in a porcelain crucible in an atmosphere of hydrogen, and cast into sticks.

Metallic thallium is bluish white; it is extremely soft and almost devoid of tenacity and elasticity.

When exposed to the air it becomes quickly covered with a film of oxide; the tarnished metal when plunged into water reassumes its metallic lustre, the oxide film being quickly dissolved.

On the 1st of November 1772 he deposited with the Academy a sealed note which stated that sulphur and phosphorus when burnt increased in weight because they absorbed "air," while the metallic lead formed from litharge by reduction with charcoal weighed less than the original litharge because it had lost "air."

The gas given off in the reduction of metallic calces by charcoal he at first supposed to be merely that contained in the calx, but he soon came to understand that it was a product formed by the union of the charcoal with the "dephlogisticated air" in the calx.

It is not reduced to the metallic condition on heating with carbon.

It thus appears that iron was manufactured from meteorolites which had fallen to the earth in an almost pure metallic state, possibly long before prehistoric man had learnt how to dig for and smelt iron in any of the forms of ore which are found on this planet.

Its value as a dyestuff depends on its power of forming insoluble compounds (lakes) with metallic oxides.

No further practical advance appears to have been made in the design or construction of the instrument till the year 1723, when John Hadley (best known as the inventor of the sextant) presented to the Royal Society a reflecting telescope of the Newtonian construction, with a metallic speculum of 6-in.

In Short's first telescopes the specula were of glass, as suggested by Gregory, but he afterwards used metallic specula only, and succeeded in giving to them true parabolic and elliptic figures.

The composition of metallic specula in the present day differs very little from that used by Sir Isaac Newton.

Partly for these reasons the reflecting telescope with metallic mirror has never been a favourite with the professional astronomer, and has found little employment out of England.'

An oblong metallic box fitted with pivots, whose bearings are attached to the triangular beams, forms the tube for two parallel telescopes; these are separated throughout their length by a metallic diaphragm.

On this principle the use of the level is abolished, the telescope is mounted on a metallic float, and it is assumed that, in course of the rotation of this float, the zenith distance of the axis of the telescope will remain undisturbed, that is, of course, after the undulations, induced by the disturbance of the mercury, have ceased.

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.

The Frictional Generation Of Heat In A Metallic Wire Conveying A Current Can Be Measured In Various Ways, Which Correspond To Slightly Different Methods.

Dewar and Jones suggest that in the latter reaction it is the metallic nickel which is probably the reducing agent effecting the change, since it is only dissolved in any quantity when the anthracene hydrocarbon is produced.

The air receives heat from an external furnace just as water does in the boiler of a steam-engine, by contact with a heated metallic surface, but it takes up heat from such a surface with much less readiness than does water.

The waste of heat in the chimney gases is accordingly greater; and further, the metallic shell is liable to be quickly burned away as a result of its contact at a high temperature with free oxygen.

It is to internal combustion that they owe their success, for it enables them to get all the heat of combustion into the working substance, to use a relatively very high temperature at the top of the range, and at the same time to escape entirely the drawbacks that arise in the air-engine proper through the need of conveying heat to the air through a metallic shell.

The earliest form of Leyden jar consisted of a glass vial or thin Florence flask, partly full of water, having a metallic nail inserted through the cork which touched the water.

To Franklin also we owe the important knowledge that the electric charge resides really in the glass and not in the metal coatings, and that when a condenser has been charged the metallic coatings can be exchanged for fresh ones and yet the electric charge of the condenser remains.

All the lugs on one side are connected together, and so also are all the lugs on the other side, and the two sets of tin foils separated by sheets of mica constitute the two metallic surfaces of the Leyden jar condenser.

In 1853 works were established for the manufacture of white oxide of zinc from a calamine found here, in the next year metallic zinc was produced, and in 1865 the first sheet zinc made in America was rolled here.

It is soluble in water and combines with many metallic chlorides to form double salts.

Metallic products represent about three-fourths of the total, but the feature of recent years has been the rising importance of hydrocarbons and gases, and of structural materials, and indeed of non-metallic products generally.

The colour is iron-black and the lustre metallic; hardness 6, specific gravity 5.2.

The colour is brass-yellow, and the lustre metallic; the streak, or colour of the powder, is greenish-black.

The di-iodide is obtained as green metallic scales on passing iodine over red-hot tungsten.

The Hartville ores are remarkable for their high grade and purity, running from 60 to 70% metallic iron, with 22 to 5% silica, and only traces of sulphur and phosphorus.

The majority of the metallic chlorides are solids (stannic chloride, titanic chloride and antimony pentachloride are liquids) which readily volatilize on heating.

All the metallic chlorides, with the exception of those of the alkali and alkaline earth metals, are reduced either to the metallic condition or to that of a lower chloride on heating in a current of hydrogen; most are decomposed by concentrated sulphuric acid.

Some metallic chlorides readily form double chlorides, the most important of these double salts being the platinochlorides of the alkali metals.

It consisted simply of a light metallic needle balanced on a pivot like a compass needle.

Among the city's manufactures are lumber, furniture, baskets, pearl buttons, cars, carriages and wagons, Corliss engines,waterworks pumps,metallic burial cases, desks, boxes, crackers, flour, pickles and beer.

They may be prepared by dissolving or suspending a metallic oxide or hydroxide in water and saturating the solution with chlorine; by double decomposition; or by neutralizing a solution of chloric acid by a metallic oxide, hydroxide or carbonate.

In some cases it is very difficult to distinguish niello from black enamel.; but the black substance differs from true enamel in being metallic, not vitreous.

Copper has been mined for many years, and in 1906 and 1908 constituted New Mexico's most valuable metallic product, the value of the yield in these years being $ 1, 35 6, 533 and $658,858 respectively.

The term " electricity " is applied to denote the physical agency which exhibits itself by effects of attraction and repulsion when particular substances are rubbed or heated, also in certain chemical and physiological actions and in connexion with moving magnets and metallic circuits.

Watson carried out elaborate experiments to discover how far the electric discharge of the jar could be conveyed along metallic wires and was able to accomplish it for a distance of 2 m., making the important observation that the electricity appeared to be transmitted instantaneously.

If, however, pairs of metallic disks, made, say, of zinc and copper, are alternated with disks of cloth wetted with a conductor of the second class, such, for instance, as dilute acid or any electrolyte, then the effect of the feeble potential difference between one pair of copper and zinc disks is added to that of the potential difference between the next pair, and thus by a sufficiently long series of pairs any required difference of potential can be accumulated.

He discovered that they had the power of affecting the electric conductivity of materials when in a state of powder, the majority of metallic filings increasing in conductivity.

C. Rntgen of Munich made in 1896 his remarkable discovery of the so-called X or Rntgen rays, a class of radiation produced by the impact of the cathode particles against an impervious metallic screen or anticathode placed in the vacuum tube.

Its alloy with tin (bronze) was the first metallic compound in common use by mankind, and so extensive and characteristic was its employment in prehistoric times that the epoch is known as the Bronze Age.

The difficulty of effecting this double object in one operation was so great that in subsequent experiments the aim was merely to concentrate the matte to metallic copper in converters of the Bessemer type.

The concentration was effected without any embarrassment till metallic copper commenced to separate and chill in the bottom tuyeres.

Under favourable conditions in the larger works of the United States the cost of converting a 50% matte to metallic copper is generally understood to be only about 1 o to iw of a cent per lb.

Sulphur dioxide is then blown in, and the precipitate is treated with iron, which produces metallic copper, or milk of lime, which produces cuprous oxide.

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.

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.

The heaps are moistened with ferric chloride solution, and the reaction is maintained by the liquid percolating through the heap. The liquid is run off at the base of the heaps into the precipitating tanks, where the copper is thrown down by means of metallic iron.

Electrolytic copper should contain at least 99.92% of metallic copper, the balance consisting mainly of oxygen with not more than o oi% in all of lead, arsenic, antimony, bismuth and silver.

Finally, these observers traced the variation to the fact that the wire supporting the aluminium needle as well as the wire which connects the needle with the sulphuric acid in the Leyden jar in the White pattern of Leyden jar is enclosed in a metallic guard tube to screen the wire from external action.

In order that the needle may project outside the guard tube, openings are made in its two sides; hence the moment the needle is deflected each half of it becomes unsymmetrically placed relatively to the two metallic pieces which join the upper and lower half of the guard tube.

Nineteen of the 54 steamers belonged to a subsidized national line whose West Coast service once extended to San Francisco, California, and a large part of the others belongs to a Lota coal-mining and copper-smelting company which employs them in carrying coal to the northern ports and bringing back, metallic ores for smelting.

It prevents the precipitation of many metallic hydroxides by caustic alkalis.

But by the addition of some antiseptic to the ointment its defensive action would be converted from passive to active, and its power to prevent infection would become greater; and if inflammation had already set up in the skin, the addition of opium, belladonna, or cocaine would lessen local pain; and an astringent, either metallic or organic, would restrain inflammation and accelerate repair.

Fused borax dissolves many metallic oxides, forming complex borates which in many cases show characteristic colours.

It usually occurs as lamellar or glanular masses, with a tin-white colour and metallic lustre, in limestone or in mineral veins often in association with ores of silver.

Antimony, however, occurs chiefly as the sulphide, stibnite; to a much smaller extent it occurs in combination with other metallic sulphides in the minerals wolfsbergite, boulangerite, bournonite, pyrargyrite, &c. For the preparation of metallic antimony the crude stibnite is first liquated, to free it from earthy and siliceous matter, and is then roasted in order to convert it into oxide.

For rich ores the method of roasting the sulphide with metallic iron is sometimes employed; carbon and salt or sodium sulphate being used to slag the iron.

It combines directly with sulphur and phosphorus, and is readily oxidized when heated with metallic oxides (such as litharge, mercuric oxide, manganese dioxide, &c.).

Antimony compounds when heated on charcoal with sodium carbonate in the reducing flame give brittle beads of metallic antimony, and a white incrustation of the oxide.

Metallic antimony was utilized to make goblets in which wine was allowed to stand so as to acquire emetic properties, and "everlasting" pills of the metal, supposed to act by contact merely, were administered and recovered for future use after they had fulfilled their purpose.

By screening the various parts with metallic plates in connexion with earth, Beetz further proved that, contrary to the opinion of earlier observers, the seat of sensitiveness is not at the root of the jet where it leaves the orifice, but at the place of resolution into drops.

Ores containing gold or silver are almost invariably assayed in the dry way; that is, by fusion with appropriate fluxes and ultimate separation of the elements in the metallic form.

In the first the gold or silver is made to combine or alloy with metallic lead, the other constituents of the ore being separated from the lead as slag.