Dismounting to assist her, Walcott discovered that the horse had turned a slab of shale that contained fossil crustaceans of an especially ancient and unusual type. Snow was falling—winter comes early to the Canadian Rockies—so they didn't linger, but the next year at the first opportunity Walcott returned to the spot. Tracing the presumed route of the rocks' slide, he climbed 750 feet to near the mountain's summit. There, 8,000 feet above sea level, he found a shale outcrop, about the length of a city block, containing an unrivaled array of fossils from soon after the moment when complex life burst forth in dazzling profusion—the famous Cambrian explosion. Walcott had found, in effect, the holy grail of paleontology. The outcrop became known as the Burgess Shale, and for a long time it provided "our sole vista upon the inception of modern life in all its fullness," as the late Stephen Jay Gould recorded in his popular book Wonderful Life.
沃尔科特跳下马来扶她，却发现马将一块页岩圈了个身。页岩里有一种特别古老、特别罕见的甲壳纲动物的化石。天正下着雪——在加拿大的落基山脉，冬天来得很早——因此他们没有久留。但是，到了第二年，沃尔科特一有机会就回到了现场。他沿着岩石估计会滑行的路线攀登了200多米，爬到接近山顶的位置。在海拔2438米的地方。他发现了一个页岩露头，长度大约相当于城市的一个街区，里面蕴藏着一大批化石，远自复杂生命大爆爱——即著名的寒武纪大爆发——之后不久的时候。沃尔科特发现的实际上是古生物学的圣杯。那片露头后来被称之为布尔吉斯页岩，取自它所在的山冈的名字。在很长时间里，正如已故的斯蒂芬·杰伊·古尔德在他深受欢迎的著作《奇异的生命》中所说的，它是“惟一向我们充分展示现代生命起端的地方”。

Gould, ever scrupulous, discovered from reading Walcott's diaries that the story of the Burgess Shale's discovery appears to have been somewhat embroidered—Walcott makes no mention of a slipping horse or falling snow—but there is no disputing that it was an extraordinary find.
在阅读沃尔科特日记的过程中，向来细心的古尔德发现，有关发现布尔吉斯页岩的故事似乎有点儿添油加醋——沃尔科特既没有提及马失前蹄，也没有谈到天下着雪——但那是一项非同寻常的发现，这是无可争议的。
It is almost impossible for us whose time on Earth is limited to a breezy few decades to appreciate how remote in time from us the Cambrian outburst was.
我们在地球上只能存在短短的几十年，因此几乎不可能体会到寒武纪大爆发离我们有多么遥远。