Phantom of the Poles

And this is mentioned in passing in a conversation between, I think it's Crozier and Fitzjames.

But William Reid is the author of a book called The Phantom of the Poles, published in 1906.

And the author reads book posits all kinds of evidence for the hollow earth based on scientific observations in the Arctic regions.

I read this years ago from an online facsimile by John Bruno Hare uploaded in 2005, which I can no longer see anywhere online.