1000000030

1jUite red, but not enopgh ro melt

th~

coppcr. The fur–

riCe of the copper will gradually lofe irs meraJline fplen–

dor, and pUl un the appearance of a reddifh eanh. From

time tO time nir

th~

61ings with a little rod of copper or

iroo, and leave your met:tl expofed to the fallle degree of

fire

tiJl it be always calcioed.

'/'0

r;¡tJfeilale Ihe

C.lx

01Copper, and rduce

lo Cop–

per,

~dloring

il'

Phlogif/M.

MI x the calx of copper with thrice as much of the

black flux ; put the mixture into a good crucible, fo as

6J1

two thirds thereof, and over it put a layer of fea–

ralt a finger tbick. Cover the CTocible, and fO! it in a

melting furnace; heat it graduaJly, and keep it mode–

tately red tiJI the decrepitation of the fea-falt be overo

Then raife the fire

confidera~ly

by means of a good pair

of perpetual bellows; fatisfy yourfelf that the maner is

¡>trfeét fufion, by dipping into the crucible

iron

wire; cootioue the 6re in this degree for half a quaner

of an hour. Wben the crucible is cold, you wiJl 6nd at

its bottom a bunon of very 6ne copper, which will eafily

reparate from the faline fcoria at topo

To diffolve Copper in Ihe Minrral Acidl.

a fand-bath, in a.•ery gentle heat, fet a matras

tootaining foms copper filings.; pour on them twice their

weight of oil of vitriol. 'fhat acid wiJl prefently auack

tbe copper. Vapours will-rife, and ilfue out of the neck

of ihe matras. A van OIimber of bubbles will .fcend

from the furface of the metal to the top of the liq"or,

aod the liquor will ,cquire abeautiful blue colour. When

the copper is dilfolved, put

a liule and a linle more,

liU you perceive the acid no longer ,éls upon it. Then

decaDt the liquor, and let it nand quiet in

cool place.

{hon time great numbers of beautiful blue crynals

"'¡U !haot in it. Thefe crynals are called

vilriol 01

~#er,

M.e vilriol.

They dilfolve eafily iD water.

IR.

O N.

fiparale

IN"

/rom

iI,

Orto

POtlND ioto a coarfe powder the manial nones or

earths ,out of which you deflgn to extraét the iron:

Roan this powder in a ten under the muffie for fome mi–

nutes, and let your 6re be brill" Then let it cool,

beat it very 6ne, and roan it

fecond time, keeping it

under the muffie till it emit

more fmell.

Then mi" with this powder a Bux compofed of three

pam

of nitre fixed with tanar, one part of fufile glafs,

and half

pan of borax aod chArcoal·dun. The dofe

of tbis reducing flux mun be tbrice the weight of the

ore.

Put this mixture into a good crucible; com

with

2boUI half a fiDger thick of Tea·falt; over the crncible

put itl cover, and lute it on with Windfor·loam made

into a pane with water. Having thus pTepared your

crucible, fet it io a melting furnace, which you mun 6J1

1lp with charéoal. Light the

~re,

and let·it kindle by

"elltl~

degrm, till the crucible become red·hot. When

t'he dempitation of the fea·falt is over, raife your 6re to

·Vo~.

No. 35.

the highen by the blan of a pair of perpetual bellows, or

rather feveral. Keep up this intenfe degree of heat for

three quarters of an liour, or a whole haur, taking care

that during all this time the fumate be kept cont!antly

filling up with frefu coals as the fonner confume. Then

take your crucible out of cbe fnrnace; nrike the plve–

ment

which you fet it feveral

tim~

with a hammer

and let it nand to cool: Break it, and you will find

therein a regulus of iron covered with flag.

In fmelting.houfes iron ore i.s fufed amidll charcoal, the

phlogifion of which combines with the manial eanh, and

gim it the metalline formo The iron lhus mehed runs

down to the bottom of the furDace, from whence it is let

out into large moulds, in which it rakes the (hape of ob–

!ong blocks, called

pigJ

oriron. This iron is ¡¡iJl very

Impure, and qUIte .unmalleable.

!t,

want of duélility

after the fir/l melting arifes panly from hence, lbat, noto

withnandlng lhe previous roafling which lhe ore under–

went, there ·nill renl.iDs, afrer this firH fufion,

c~fi

derable quantity of fulphur or arrenic combined with the

metal.

cenain quantity of quick.lime, or of

non~

tbat

will burn to lime, is frequently mixed with iron ore on

putring it into the fmehing furnace. The lime being ao

abforbent eanh, very apt to unite with fulphur aod arfe–

nic, is of ufe tO feparare thore minerals from the iroD.

It is alfo of ufe ro mix fome fuch manees with the

ore, when the nones or eanhs which naturally accom·

pany it are very fufible; for, as the iron is of difficult

fufion, it may happen that the' eanhy malters mixed with

the iroo (hall melt as eafily as the ·mml, or perhaps more

eafily. In fuch a care there

¡,

no feparatioo of the

eart~~

from the.

metallin~

part, both of which melt and

preclpltate together promtfcuoully : Nowquick·lime, be–

ing extremely refraélory, ferves on this occafion tO check

the mehing of thofe mattera wbich are too fufible.

Yet quick.lime, notwithnanding itsrefra(tory qualiry,

may fomelimes be of-tlfe as a flux for iron: Tltis is the

care when {he ore happens to be combined with fubllan–

ces which, being united wim lime, Tender it fulible: Such

are all arfenical mauers, and even fome eanhy malters,

which, being combioed with quick.lime, make a fufible

compouod.

When the ore of an iroo mine il found dillicult to re·

duce, it is ufually negleéted even though it be rich; be.

caufe iron 'being very common, people chufe to work

Ihofe mines only whofe ores are fmehed "ith the molt

e2fe, and require the lean confumption of wood.

Yet refraétol') ores are not to be ahogether rejeélcd,

when another iron ore of

different quality is found near

them. For it often happens, that two feveral iron ores,

whicR being worked feparately are very dillicult

m.·

n'ge, and yield at lan but bad iron, become very traéla–

ble, and yielrl excellent iron, when rmeherl rogether:

And accordingly fuch mixtures are often made at iron·

works.

The iron obtained from ores by the firn fufion may be

divided into twO forlS. The one, when cold, rcfifls the

hammcr, doth not eafily break, and isin fome meafure ex–

tenfible on the anvil; but if nrucK with a hammer, when

red·hot, Biel into many pieces': This

fon

iron hath

;¡),

v.ys