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иxL(zhng)y

r(sh)g2021-01-09 18:52:54 иԇ ҪͶ

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иxL(zhng)yұg(sh)l(f)չ

P(gun)иxL(zhng)y

Unlike in the Americas, where metallurgy was a very late and limited development, Africans had iron from a relatively early date, developing ingenious furnaces to produce the high heat needed for production and to control the amount of air that reached the carbon and iron ore necessary for making iron. (50)

~R

metallurgy n. ұ (g(sh),W(xu))

ingenious  adj.

1(ָ) Ļ(jin)εķQ(f)s}`ɵ

2(ָ)O(sh)Ӌ(j)(d)ضɵ

3(ָ)eIJõ,

furnace  n. ۠t

һ(run by steam) ^Z(dng)~printing pressesע@run^Z(dng)~Ǻfound@׻

ģͨ^\(yn)

(by hand)~Zprinting pressesעrather than(j)lZ֮ǰҲ^һ(g)~ǡ

ģͨ^

(to produce a thousand pages in anhour rather than thirty.) ^Zitָ@`(ni)

ģa(chn)һǧ?jin)һ(g)Сr(sh)(ni)ҪʮСr(sh)

ɣoperators found it possible

g

һ(Unlike in the Americas),~Z

ģ

(where metallurgy was a very late and limited development) ,ľ

ģұg(sh)l(f)չdz

(developing ingenious furnaces) ,^Z(dng)~

ģl(f)չ˪(d)ضɵ۠t

ģ(to produce the high heat neededfor production),^Z(dng)~

ģɮa(chn)ұFҪĸߜ

壺(to control the amount of air) ,^Z(dng)~

ģƿ՚Ĕ(sh)

( that reached the carbon and ironore) ľair

ģ|̼FV

ߣ(necessary for making iron. ) ~Zair

ģ(du)ұFбҪ

ɣAfricanshad iron from a relatively early date

g

ұg(sh)l(f)չdzޓF^l(f)չ˪(d)ضɵ۠tɮa(chn)ұFҪĸߜأҿƽ|̼FVĿ՚ԝMұFҪ

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