Under the microscope, the stuff they're after looks like a clean, structurally sound brick wall. If the wall looks ratty or crumbly, it's no good.

在显微镜之下，原本看起来很干净的表面其实像砖墙一样凹凸不平，如果这堵墙看起来破烂不堪或疏松易碎，就说明珍珠层没有用。

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It has brick houses, clean running water and even school buildings.

有砖房、干净的自来水、甚至还有校舍。

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The rubber floor provides a clean and comfortable surface but at the same time visually creates a strong contrast to the raw and textured brick walls and vaulted ceiling.

橡胶地板提供了一个干净、舒适的表面，但同时与砖墙的原料和质感和拱形天花板又形成了视觉上强烈的对比。

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The piers are only two brick-lengths deep, and the arches rise fluidly from the piers, resulting in a sense of clean planarity.

WSJ: Prim Grandeur, Elegant Geometries | Charles Bulfinch | Lancaster Meetinghouse | By John Wilmerding