What does 金 have in common with triggers/guns?


I read the word 「引き金」and the definition is:

> １ 小銃・ピストルなどの、指で引く発射装置の金具。
>
> ２ ある事態を引き起こす直接の原因。きっかけ。「授業料の値上げが―となって大学紛争が起こった」 起因(きいん) ⇒類語辞書で詳しい使い方を調べる
> 誘因(ゆういん) 動機(どうき) モチーフ

But why is 金 connected to the meaning of "trigger"? How is "pulling
money"「引き金」representative of a "gun" or "trigger"?




「金」 in 「引{ひ}き金{がね}」 does not represent "money" but "metal". "Metal" is
translated as 「金属{きんぞく}」 and "metal fittings" are translated as 「金具{かなぐ}」.
「引き金」 is the part of a gun that is made of metal and is for triggering the gun
to fire. In English, "trigger" also means the part of a gun as a noun, and "to
cause something" as a verb.

References:

**かな‐ぐ【金具】**

> 器物・器具に取り付ける金属製の小さな部品や細工物。鐶(かん)・錠・引き手の類。

source: デジタル大辞泉
<http://dictionary.goo.ne.jp/leaf/jn2/43429/m0u/%E9%87%91%E5%85%B7/>

金属 <http://dictionary.goo.ne.jp/srch/je/%E9%87%91%E5%B1%9E/m0u/>

Word origin for 金: <http://gogen-allguide.com/ka/kane.html>




「金」 in 「引{ひ}き金{がね}」 does not represent "money" but "metal". "Metal" is
translated as 「金属{きんぞく}」 and "metal fittings" are translated as 「金具{かなぐ}」.
「引き金」 is the part of a gun that is made of metal and is for triggering the gun
to fire. In English, "trigger" also means the part of a gun as a noun, and "to
cause something" as a verb.

References:

**かな‐ぐ【金具】**

> 器物・器具に取り付ける金属製の小さな部品や細工物。鐶(かん)・錠・引き手の類。

source: デジタル大辞泉
<http://dictionary.goo.ne.jp/leaf/jn2/43429/m0u/%E9%87%91%E5%85%B7/>

金属 <http://dictionary.goo.ne.jp/srch/je/%E9%87%91%E5%B1%9E/m0u/>

Word origin for 金: <http://gogen-allguide.com/ka/kane.html>

