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在很多電影和傳說中都有流沙的影子，它在人們的印象中是沙漠里極其危險的東西。不過，根據(jù)科學家最近的研究，流沙并沒有想象中那么危險，人們完全可以借助浮力在流沙中“游泳”，而不至遭遇“滅頂之災”。

Quicksandconsists of abuoyantblend of roundgranulesof light sand, blended with water, or of light soil andgrittymud, or of mud peppered with pebbles. Water injects itself into the grains of any one of these mixtures, which separates and lifts them, causing them totumbleover one another, and rendering them helpless to support weighty objects.

Quicksand typically surfaces near the deltas of mighty rivers, or near shores, where a layer of stiff clay below collects and retains the water. Quicksand does not suck unsuspecting victims to their untimely deaths; a theory espoused me most until recently. Thisnightmarishtheory did, however, provide good fodder for a host of low-budget horror films!

The discovery of quicksand's buoyant properties,akinto those of the salty Dead Sea, quashed this prevalent theory. Since quicksand is saturated with liquid, and far outweighs water, it allows anything or anyone who steps into it, to float higher than possible in water alone. The key to swimming in thisnon-chlorinatedswimming hole is slow motion. By moving slowly, when initially landing in quicksand, one provides the quicksand with the lead-time necessary to flow around one's body, thereby making swimming or floating possible.

quicksand: 流沙

buoyant: 有浮力的

granules: 顆粒

gritty: 含沙的

tumble: 翻動

nightmarish: 噩夢似的、不愉快的

akin: 類似的

non-chlorinated: 非綠色的

（英語點津 Annabel 編輯）