Page:Polar Exploration - Bruce - 1911.djvu/80

76 the animal was within a hundred yards of a congregation of twenty-five men, whose eyes, it must be confessed, wandered from the reader more than once, but not one of whom had seen the bear though he was in full view. The change of scene need not be described in this place, but before the bear was within thirty yards of the ship, he lay a victim to the devout mate and his congregation. Yellow ice was the explanation!

Now if some of this ice be collected and melted, a yellowish deposit is left, which on microscopic examination is found to be composed mainly of diatoms. These diatoms and other algæ spread themselves over the entire surface of Arctic sea ice, and the yellow patches indicate specially favourable growing-places for them. The distribution of these Arctic diatoms is somewhat different from that of those on the Antarctic ice. In the Arctic they are more on the surface, while in the Antarctic they are confined more or less to a thin lamina at sea-level, above which lies the remnant of the winter snow. In fact, the diatoms of Arctic ice are altogether different species from those of Antarctic ice. And while diatoms have nothing to do with bears, it is quaint to notice that in the Arctic Regions the yellow ice patches hide the polar bear from vision; in the Antarctic regions, where the yellow diatom material is,