It's ambiguously worded, but I don't read that to imply that he thinks every point on the 50th parallel is equidistant from the pole and the equator. Break the

It's ambiguously worded, but I don't read that to imply that he thinks every point on the 50th parallel is equidistant from the pole and the equator. Break the clauses into separate sentences and you'll see what I mean: Every point on this line is the same distance from the equator. Every point on this line is the same distance from the frozen pole. These are both true sentences, they just don't refer to the same distance.