OF CORNWALL. 181 
conftant work and water, will employ one man and five boys ; and 
one hundred hacks (each hack containing twelve gallons) are Lamped, 
walked, and fitted for melting at the rate of fix-pence per lack (or 
fifty {hillings per hundred) more or lefs fomewhat, according to the 
quality of the ore, in the fpace of a few days. For bruifing the 
tin-ore into a finer powder, formerly they ufed the crazing-mill (Ca- 
rew, page 12) after the ore was Lamped, an engine not much 
unlike the prefent griL-mill ; but Sir Francis Godolphin before- 
mentioned (as it is fuppoled) either invented or improved this much 
more effectual engine the water Lamping-mill here exhibited, lb as 
it might ferve all purpofes, and the other has been ever fince difuled. 
Tin, being drejjed ^ is carried in hacks under the general name of sect.xviil 
Black-tin (though what is called Frame-tin is ufiially of a yellow- Of melting 
ifh earthy colour, and home other ruddy brown, and Ibme cinere- n 
ous and whitifh) to the melting-houfe upon horfes, each horfe car- 
rying about three hundred pounds weight. Here, the parcel brought 
is firL allayed ; in order to which, either the whole parcel is emp- 
tied into clean timber hutches, and there well mixed, or a little 
out of every fack is taken by the affayer, and well mixed together, 
that the aLay of that little parcel may afcertain the real quality of 
the whole : for it muL be obferved, that although the procefs of 
cleanfing all forts of tin is nearly the fame, and after this cleanfing 
all goes by the name of Black-tin, yet each parcel of every work 
may be of different value, according as it is more or lefs Ikilfully 
dreffed, and according as the different pabula with which it is in- 
corporated do either promote or obviate the fufion of the metal. 
That this “ black-tin therefore is ever all of the fame richnefs 
and yields alike,” as Dr. Woodward s was informed, is a great mi- 
Lake. Kal, for inLance, viz. wild-iron, is reckoned to mix well, 
and melt kindly with tin-ore, and increales the quantity of melted 
tin in a greater proportion than the quality is thereby debafed, as 
we find by that of Huel-boys mine in St. JuL, and that of other 
places ; fuch ore will therefore yield one quarter of a twentieth 
part more than ore of a much finer appearance to the eye. The 
melter is not paid in money for melting the tin brought, but by 
allotment of fuch a fhare in twenty : for the charges of coals, la- 
bour, and utenfils, expended in the fufion, the melter has ufually 
the other twelve in twenty parts remaining to the owner ; fome 
tin however will bring the owner twelve and a half and thirteen 
out of twenty, which is the moL that is given : on the other hand, 
fome black tin has fuch a quantity of other metal, or of its own 
Lubborn feeder adhering to it, that it will not bring more than 
5 Catalogue, vol. II. page 31, m. 26. 
A a a 
eight 
