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Book IX: Smelting Ore

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BOOK IX.
391
charcoal and earth, as is also a large crucible, one-half of which lies under the
furnace and the other half outside it, into which runs the lead. The
smelter, having first skimmed off the slags and other things with a hoe, pours
the lead with a ladle into moulds, taking out the cakes after they have
cooled. At the back of the furnace is a rectangular hole, so that the fire
may be allowed more draught, and so that the smelter can crawl through it
into the furnace if necessity demands.
The Saxons who inhabit Gittelde, when smelting lead ore in a furnace
not unlike a baking oven, put the wood in through a hole at the back of the
furnace, and when it begins to burn vigorously the lead trickles out of the
ore into a forehearth. When this is full, the smelting being accomplished,
the tap-hole is opened with a bar, and in this way the lead, together with the
slags, runs into the dipping-pots below. Afterward the cakes of lead, when
they are cold, are taken from the moulds.
In Westphalia they heap up ten wagon-loads of charcoal on some hillside which adjoins a level place, and the top of the heap being made flat,
straw is thrown upon it to the thickness of three or four digits. On the top of
among the spoil captured by Thotmes III. Leaden objects have frequently been found in
Egyptian tombs as early as Rameses III. (1200 b.c.). The statement is made by Pulsifer
(Notes for a History of Lead, New York 1888, p. 146) that Egyptian pottery was glazed with
lead. We have been unable to find any confirmation of this. It may be noted, incidentally,
that lead is not included in the metals of the " Tribute of Yii " in the Shoo King (The Chinese
Classics, 2500 B.c. ?), although silver is so included.
After 1200 or 1300 B.c. evidences of the use of lead become frequent. Moses (Numbers
xxxi, 22-23) directs the Israelites with regard to their plunder from the Midianites (1300 B.c.) :
" Only the gold and the silver, the brass [sic], the iron, the tin, and the lead. Everything
" that may abide the fire, ye shall make it go through the fire, and it shall be clean ; neverthe" less, it shall be purified with the water of separation, and all that abideth not the fire ye shall
" make go through the water." Numerous other references occur in the Scriptures (Psalms
jrii, 6 ; Proverbs xvii, 3 ; xxv. 4, etc.), one of the most pointed from a metallurgical point of view being that of Jeremiah (600 b.c.), who says (vi, 29-30) : " The bellows
" are burned, the lead is consumed of the fire ; the founder melteth in vain ; for the wicked
" are not plucked away. Reprobate silver shall men call them because the Lord hath rejected
" them." From the number of his metaphors in metallurgical terms we may well conclude that
Jeremiah was of considerable metallurgical experience, which may account for his critical
tenor of mind. These Biblical references all point to a knowledge of separating silver and lead.
Homer mentions lead (Iliad xxiv, 109), and it has been found in the remains of ancient Troy
and Mycenae (H. Schliemann, " Troy and its Remains," London, 1875, and " Mycenae,"
New York, 1877). Both Herodotus (1, 186) and Diodorus (11, 1) speak of the lead used
to fix iron clamps in the stone bridge of Nitocris (600 b.c.) at Babylon.
Our best evidence of ancient lead-silver metallurgy is the result of the studies at Mt.
Laurion by Edouard Ardaillon (Mines du Laurion dans l'Antiquité, Paris, 1897). Here the very
extensive old workings and the slag heaps testify to the greatest activity. The re-opening of
the mines in recent years by a French Company has well demonstrated their technical character, and the frequent mention in Greek History easily determines their date. These deposits
of argentiferous galena were extensively worked before 500 b.c., and while the evidence of
concentration methods is ample, there is but little remaining of the ancient smelters. Enough,
however, remains to demonstrate that the galena was smelted in small furnaces at low heat,
with forced draught, and that it was subsequently cupelled. In order to reduce the sulphides
the ancient smelters apparently depended upon partial roasting in the furnace at a preliminary period in reduction, or else upon the ferruginous character of the ore, or upon
both. See notes p. 27 and p. 265. Theognis (6th century b.c.) and Hippocrates (5th century
b.c.) are frequently referred to as mentioning the refining of gold with lead ; an inspection of the passages fails to corroborate the importance which has been laid upon them.
Among literary evidences upon lead metallurgy of later date, Theophrastus (300 b.c.)
describes the making of white-lead with lead plates and vinegar. Diodorus Siculus (ist
century b.c.), in his well-known quotation from Agatharchides (2nd century b.c.) with
regard to gold mining and treatment in Egypt, describes the refining of gold with lead.
(See note 8 p. 279.) Strabo (63 b.c.—24 a.D.) says (in, 2, 8) : " The furnaces for
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