Outflows of resinResinosisalro come under this general heading; but although some resin-fluxes are traced to the destructive action of Agaricus melleus in Conifers, others, as well as certain forms of Gummosis, are still in need of explanation.
The methods of chemical analysis may be classified according to the type of reaction: (I) dry or blowpipe analysis, which consists in an examination of the substance in the dry condition; this includes such tests as ignition in a tube, ignition on charcoal in the blowpipe flame, fusion with borax, microcosmic salt or fluxes, and flame colorations (in quantitative work the dry methods are sometimes termed " dry assaying "); (2) wet analysis, in which a solution of the substance is treated with reagents which produce specific reactions when certain elements or groups of elements are present.
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).
Magnetic induction, like other fluxes such as electrical, thermal or fluid currents, is defined with reference to an area; it satisfies the same conditions of continuity as the electric current does, and in isotropic media it depends on the magnetic force just as the electric current depends on the electromotive force.
The bullion left in the retorts is then melted in black-lead crucibles, with the addition of small quantities of suitable fluxes, e.g.
No evidence of smelting ores with fluxes is offered, but casting from metal melted in open fires is assumed.
Platinum is employed in oxidizing processes, and in the fusion of substances with fluxes; also in observing the colouring effect of substances on the blowpipe flame (which effect is apt to be somewhat masked by charcoal).
In Lake county, for example, very much of the argentiferous ore that is too low for remunerative extraction (limit 1903 about $12.00 per ton) is used for fluxes.'
The coarse-metal is now smelted, with coke and siliceous fluxes (in order to slag off the iron), and the product, consisting of an impure copper sulphide, is variously known as " blue-metal," when more or less iron is still present, " pimplemetal," when free copper and more or less copper oxide is present, or " fine " or " white-metal," which is a fairly pure copper sulphide, containing about 75% of the metal.
It is made up of the following operations: (z) calcination, (2) smelting in blast-furnaces to form the matte, (3) roasting the matte, (4) smelting in blast-furnaces with coke and fluxes to " black- " or " coarse-metal," (5) refining the coarse-metal.
The Sereh disease of the sugar-cane, the slime fluxes of oaks and other trees, are not only very doubtful cases, in which other organisms such as yeasts and fungi play their parts, but it may be regarded as extremely improbable that the bacteria are the primary agents at all; they are doubtless saprophytic forms which have gained access to rotting tissues injured by other agents.
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 some processes of lead-smelting, where the minerals treated contain sand, the long calciner is provided with a melting bottom close to the fire-place, so that the desulphurized ore leaves the furnace as a glassy slag or silicate, which is subsequently reduced to the metallic state by fusion with fluxes in blast furnaces.