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until the composition rises above 1Oo/oAs. Then you can get fumes in casting. As2O3 gives a characteristic white smoke and condenses out as white powder -- the classic poison of the Victorians.. You get some warning,as the fumes stink of garlic. About 20 mg of ingested As will cause death. lt is probablyunlikelythat you could get this from a lungful of fumes, but it wouldn't do you any good. Any repeated exposure would almost certainly lead to nerve damage and serious illness. lt's also a carcinogen."tu Bellows certainly sound better than that! However, the only evidence of bellows is in

swung aside as air rushed in and was pressed againstthe hole when pressurebuilt up as the air was forced out. Everything was made using native materials. The result of the experimentwas a chunk of slag with veins of p u re c o p p e r in it , s in c e h is f u rn a c e w a s a simple pit furnace rather than a shaft furnace; but it proved that the process shown in the Another t o mb p a in t in g s c o u ld wo rk . t u advantageof the bellows was that there was n o d a n g e r o f a n o x ia . (T ry b lo win g t h r o u g h a t u b e a s q u ic k lya s p o s s ib lef o r a wh i l e a n d s e e h o w q u ic k lyd iz z in e s s e t s in ! )

t o mb p a in ti ng s. No e x a mp le s of th e actual have bellows been d i s c ove r e d .Ski n bellows the sort of bellows associated with blacksmiths were barely u s e d a t all. M uch more c o m mon we r e dish bellows. For dish

AccomplishingSomething Useful. The third step in the processis to actually ma k e s o me t h i n g o u t o f the pure metal it took so lo n g t o a c q u ire . E a r l yi n E g y p t ' s h is t or y , t h e e a s ie s twa y o f d o i n g t h i s wa s t o a n n e a lit. T h a t i s , to take a piece of native (n a t u ra lly p u re) c o p p e r , bellows, a sack of leather was fixed to two a n d s imp ly b ea t i t i n t o pieces of ceramic, one the shape desired. shaped like a dish. The A n n e a lin g a ls o h a r d e n s other was flat, and could t h e c o p p e r, g i v i n g i t a " s k in " o f h a r d m e t a l . have been wood. The (rrom Figure 4: Parts of the blowpipe scheer) dish had a hole in it with L a t e r, t h e c o p p e r w a s a r e e d le a d in gto the tuyere. A n intake v a lv e melted down first and poured into an open w a s pla ce do n the leather,but no one k n o ws mo ld - a c h u n k o f ro c k o r wo o d in t o w h i c h t h e p r e c i selyho w it was made. The dish wa s basic form of the finished object has been p l a c edon th e g r ound and the reed was pu s h e d c a rv e d . T o ma k e a k n if e , c h is e lt h e s h a p eo f a i n t o the tuye r e . Then, someonewould p u t a k n if e in t o a ro c k a n d p o u r in t h e me t a l . O n c e f o o t i n the d ish, and grab a leather p u ll cool, it will be a knife-shapedpiece of metal attached to the top (see figure 2, bottom & wh ic h c a n b e a n n e a le du n t il it h a s a n e d g e . r i g h t) . Pullin gup filled the bellows with a ir, The surface of a piece of metal made in an a n d pu sh in gdo wn with the foot pushedth e a ir o p e n mo ld will b e mo re o r le s s f lat , l i k e t h e o u t thr o u g h the tuyere. When a grad u a t e s u rf a c eo f a p u d d le o f wa t e r. lt mi g h t c u p a student named John Merkel recreated an lit t le b it , s in c e t h e e d g e s c o o l f a s t e r t h a n t h e Eg y p ti ansm elti ngpit in 1981, he made a s e t "The article was f irst cast center. o f d ish b e llo ws, duplicatingthe ones in t h e approximatelyto its finishedshape,the cutting t o mb pa in ti ng sas closely as possible. T h e re edges being hammered out afterwards when w a s no u p p e r h alf to his bellows; they we re t h e me t a l wa s c o ld . T h is c o n f irms.. . t h a t t h e simply a piece of leathertied around the edge hardness of the cutting edges of antique o f a dish a n d pumped up and down. F o r a n c o p p e ra n d b ro n z eimp le me n t swa s du e s o l e l y intake valve, he cut a hole in each piece of t o h a mme rin g . S o me g rin d in gma y ha v e b e e n l e a t he r ,a n d sewed a flap to the insidewh ic h d o n e , b u t , a s t h is wo u ld re mo v et h e h a r d s k i n s Summer| 996

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Ostracon v7 n2  

Journal of ESS

Ostracon v7 n2  

Journal of ESS

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