十九世纪初的火炮瞄准具由炮身前后两个尖点构成，视线通过两尖点顶端就得出与火炮炮膛平行的瞄准线。

Gun sights introduced early in the nineteenth century consisted of fixed front and rear sight points so adjusted that the line of sight across their tips was parallel to the bore of the gun.

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十九世纪初的火炮瞄准具由炮身前后两个尖点构成，视线通过两尖点顶端就得出与火炮炮膛平行的瞄准线。

Gun sights introduced early in the nineteenth century consisted of fixed front and rear sight points so adjusted that the line of sight across their tips was parallel to the bore of the gun.

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