To prepare himself he had done some hard study of oceanography and meteorology, in the gaps between teaching geography in the department he had founded at Glassboro State College, now Rowan University. And he had gone seafaring: first fishing on small outboards past the barrier islands off New Jersey, where he would venture out so far that his colleagues thought him either lost, or mad, and later sailing across the Atlantic to Ireland and Africa.

On his voyage, a clear view of sunset or sunrise could tell him his position; but for latitude without a sextant he needed to make a geometry of the night sky, drawing an imaginary line between Polaris and his chosen navigation-star and watching where that star made its meridian transit. Finding a fixed point in the southern hemisphere was tricky until he learned to use Acrux and Gacrux, two of the brightest stars in the Southern Cross, as pointers to the southern celestial Pole. (Delta Orionis, right over the celestial Equator, was most useful for longitude.)

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