RoVAL Society f^ 
7%e Manner of making and tempering Steel, mth a Conjc5fure 
at the Method of the Ancients to Steel their Picks for 
hewing ^Porphyry 3 by ^r. Lifter. Phil. Tranil N° 20 3. 
p. 8(^5. 
THE Egyptian obelifks, thole celebrated and ftupendoiis 
monuments of antiquity, are all of porphyry, and moft of 
them are curioufly carved with a vaft number of figures, which 
was one of the ways of writing amongft the ancient Egyptians 5 
thele figures demonftrate the facility that nation had of engraving 
on porphyry, a ftone which no tool will now touch, nor any thing 
lels than emery or diamond powder affefl : Mr. Ray aflures us, 
that all the obelifks at Romey engraven with hieroglyphics, are 
of one and the lame kind of ftone 5 viz. a marble of a mixt co- 
lour, red and white, very hard, without luffering the leaft injury 
by the weather for many ages. There is certainly foinething 
loft in this age, as to the manner of fteeling of tools, and the 
procefles, now uled by moft nations, are fraudulent, and a poi- 
ibning of iron by certain mineral lalts, rather than a true mak- 
ing of fteel : The moft ancient account is that given us by Art- 
fiotle^ /. 4. c. 6. Meteorologicor. which yet is very obfcure and 
imperfedl, the palTage is this ; wrought iron itfelf may be caft 
iot as to be made liquid, and to harden again 5 and they are 
wont to make fteel thus 5 for the Scoria of iron liibfides, and is 
purged off by the bottom ; and when it hath been often defecated, 
and made clean, this is fteel3 but this they do not often, becaule 
of the great wafte, and that it loles much weight in refining 3 but 
iron is lo much the more excellent, the lefs recrement it hath ; 
thus far Arifotle. This account is a little confuled and not eafily 
intelligible 3 it is true indeed, that iron is ftill better, the more 
it is purged 3 fo in our Englijh furnaces, thofe bars, which are 
wrought out of a loop, taken out of the finery-hearth, or fecond 
forge, are much better iron than thoie made in the bloomery, or 
firft hearth, becaufe more purged of the drofs, and accordingly 
they give a double price 3 it is alfo as true, that even wrought 
iron may be melted as often as you pleafe; again, iron, as often 
as it is melted and purged, lofesmuch of its weight 3 but after 
all, iron of itfelf, how oft Ibever it is purged and refined, will ne- 
ver become fteel 3 but of it thus purged, the beft fteel doubt- 
lefs may be 'made 3 and this is the moft favourable conftru6tion 
that can be put on this paffage of Ariftotle. 
The manner of making true fteel is thus faithfully defcribed 
by Agricola^ /. p. ds re MetalUca-j and to confirm the antiquity 
Vol. III. K thereof. 
