The folding surfaces of stone wall create vivid shadow and the obtuse angle stone makes the corner look more firm and powerful.

转角处钝角转折处理更增加了浑厚有力的建筑感。

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For instance, the kiosk explains that Rothermel's deliberate perspective puts the viewer 125 yards from the copse of trees just below Cemetery Ridge in an area of the battle line known as "the Angle, " a jog in the stone wall defended by the Philadelphia Brigade.

WSJ: Capturing Gettysburg | Objects of Valor | State Museum of Pennsylvania | By Mark Yost