For two days they wove a course among the Marian Islands—a chain that ran from about thirteen degrees at its southern end, to about twenty degrees at the north. Some of the islands were steep-sided volcanoes with deep water all around, but most were so flat that they did not rise more than a yard or two above the level of the ocean, be they never so large. These were belted all round with dangerous shallows, and yet they were easy to overlook in darkness or weather. So for a few days their energies were devoted to simply not disembowelling themselves on coral-reefs, and they did not see the Manila Galleon at all.