g $ | N 'A ,.T .:U R A L ,; H I S T O R Y
pasture, or fjfhery, tin. muft needs .appear, Jo be a great bfeffing
jo this cquqty j but indeed that part of jt where the mines ehaiiee
to.% at prefent, viz. from St. Auftglweftwards, feels this advantage
moft fenfibly, lands bringing a higher rept,;the number of people
being greater, and the markets much better flocked with .buyers,
than the eaftern parts of the county where there are no mines.
s e c t . . ..The ufes o f tin are many: the ancients ufed it to make their
Ufesof tb mhtours, which ferved all the purpofes of looking-glades; but to
this conlumption luxury put a flop (lays Pliny) hy introducing of
filver: in other particulars their ules of .this metal were much the
lame as thofe of the prelent age, though notffejmany. Tin is: ufed
in tinning brafs and copper furniture ; q£ the kitchen, in fodering
pipe and fheet-lead, in making o f latfin, bell-metal, hard-wares,
in lining of looking-glafles, in fyrgery, medicine, and painting, frmfe
above all in making pewter, which in feme meafure is; ufed in all
civilized nations, by every degree, from the pooreft day-labourers
to the prince upon the throne, there being hardly a houfe in Europe*
or any part of the world where commerce reaches,, but has. feme
pewter: in all thefe particulars the confemption is as general as the
ufe, and frelh demands and frelh fepplies are perpetually quickening
and urging on one another.
s e c t . xx. Tin is the lightefrof all metals, being reckoned nearly to'water as
SutsOT- 7321 to io o o '; the lofteft- of all metals, (lead only excepted) and;
gine, con- the Icaft fixed in fire ; it cafily. mixes with other metals, but imparts
-a brjttlenels.to aUj aqua regia^is;itSfproper natural menfhmm;
Tin in its. natural ftateandhardeft, bed muft,' I fhould thinks be
Coeval to reckoned coeval with the. creation ; for it is found in bunches and
the creation, fpof-g in . the granite, and> the much harder; ftone. o f the Elvari. kind,,
ftones which can give no fefpicion of their having: ever been diflolved
and reformedfanicz the firft induration of fclids; in laxer nidus’s the particles
of tin may have fluctuated and changed fitiigrions. It has been
imagined that tin fettled in fuch bunches by the. percolation, of
waters charged with tin, but thefe bunehes .are frequently found in
feparate blocks of ftone, open to day, and. fubjedt to no moifture
but that o f the heavens, and confequently to. no percolation. Again :
In percolation, either the texture of thefe ftones would in a great
meafure refift the paflage of the tin, or would freely permit i t ; in
the firft cafe, we fhould find the tin, condenfed near the furface;
in the. latter, find it fenk and collected near the bottom; but it
is difperfed without any regard to either.
r But in the computation allowance ihould be made fox the different purity of the weighed
specimen. ’• 1^31 i ~ '
T i n
, Tjnyearly:approaches toTilvei? in coldur, but has fo much. more Its connex-
fulphu-r ifmt, that fr? .quickly-tarnifhes iri the air Or moifture-, arid is ^ witil f f
re^My- not"fev-fubje£t toehold ffl^Cpas'itsTifter lead, which is teekon-
;e§r?n inferior ifietal;; frpi, • befilfes: - the. ■ colour, it has feveral properties
in eorympayCth filver, anctfigquient connexions with ft; diflolved
Atfttong^qi(Mil®raws ■ bitteTfl 'a#well' ’.as; filled with filver
obftinaiMy adher y to -i&- an,d rqfift's0 lead almort^s much as filver. ’
^ilvMrt^hpygh ,npt '-of the .purejfewiid^ ^ may be estfta&ed .from tin \ '
In tti|~neigIb<^rooodrpf Grq^M|ai,m^vja-. in Pemlfefnpus for'the
mines heat-fe) ,|^tEe Gqlloquirijf^hich although a mane ‘of tin, yet
,%oW and thgn ui^fQllowing> thfe^eins .thereof,, .th^y meet with rich
'ores of filveiyHwhich they call Lipta '.
4 Native hinjp'or tin found irt'the Cornifh mines in*,,a metallic ftate, Native tin.
[1 am not certafefthat lever faw; frut March :2T, 1747, tyiewinga
rich .piece! of tin-ore* from Boflehari in^the Iparifh o f 'M juft ima
microfeope, I thought I &w,sa fmall lift, of-maturate.# fin, white,
{fhining like a thread of melted pewter; I then..took a, greater magnifier,,
and plainly perceived the fame "lift; but intepding . to try
further experiments to afcertain the tfut-h, I could, not afterwards
.find the fpecimen,. and therefore do not aftert the matter of fad.
Agricola, affetts, .that this metal is^nO where )found fo -pbre as to be
mafledhle?; but .the * learned' Df.:Qrew7 (Mufeum ■ R. S. page' 3-28!)
.deferipeb] one fpecimen j of cc native tin lying as" it were in bright
jdrops in a brown ftone,’’"'and I «fee no reafbn why tin may hpt” pof-
fibly- bp Refined,' and the impurities of .its pabulum feparated by diT-
folvent. juicesrin the bowels pf "the* earth,, in like manner as copper
sis. Metals fas'it feems ‘ to ' mo)vare only enfhrined, more or lefs
concealed, and' wrapt up "into ores "by’ falts, felphur, .and ftone,
which, are,Sometimes removed by a fubtal menfiruum in" the ehth.
This is frequently the cafe o f copper,'femetim.es bf filve5; and gold, the.
moft perfect of paetals; .is-ftill more frequently found in a metallic than
any othpr^ftate; but with tin this very rarely happens, by rcafoh of
the fcarcity of its proper menfiruum. Sea-falt (the bafis of aqua
regia)) being the only fait we know which will operate qn tin, dif-
perfe the impurities, and releafe the metal.
. ' As white as tin is when melted, yefcyin- the ore it is generally Tmcryftais.
black, and the cryftals, -which ■ inclofe the metal, are like black
glafs. We have however feme white, feme cinereous, and feme
red tin grains, and feme of a refinous colour, but they are rare,
and I fear often thrown away by the heedlefs, although curious as
well as profitable. Stamping and dreffing do but phl^rizeb and
reduce die ore to fmaller cryftals, and the fordes which intervene
v • See Boerh; Chem. by Shaw? P*ge 97»
1 Alonfo Bsurba» page 92.
B b b
" Page 421, fee alfo Woodward’s CatVvol.I.
clafs ii. part fécond.
being