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rg2021-01-09 18:52:54 иԇ ҪͶ

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иxLyұgl(f)չ

PиxLy

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,W)

ingenious  adj.

1(ָ) Ļ򺆆εķQs}ģ`ɵ

2(ָ)OӋضɵ

3(ָ)eIJõ,

furnace  n. ۠t

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

ģͨ^\

(by hand)~Zprinting pressesעrather thanlZ֮ǰҲ^һ~ǡ

ģͨ^

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

ģa(chn)һǧһСr(ni)ҪʮСr

ɣoperators found it possible

g

һ(Unlike in the Americas),~Z

ģ

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

ģұgl(f)չdz

(developing ingenious furnaces) ,^Z~

ģl(f)չ˪ضɵ۠t

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

ģɮa(chn)ұFҪĸߜ

壺(to control the amount of air) ,^Z~

ģƿ՚Ĕ(sh)

( that reached the carbon and ironore) ľair

ģ|̼FV

ߣ(necessary for making iron. ) ~Zair

ģұFбҪ

ɣAfricanshad iron from a relatively early date

g

ޣұgl(f)չdzޓF^磬l(f)չ˪ضɵ۠tɮa(chn)ұFҪĸߜҿƽ|̼FVĿ՚ԝMұFҪ

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@ӵҪɷ־Ƿ^Z~~ZԼľ҄ձÿһɷʲôܿ@ӵĽY

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