There have been tantalizing bits of information out there regarding arctic discoveries of frozen megafauna (most notably Mammoths) with temperate climate spring/summer plant matter in their stomachs, and in some cases mouth/teeth (having been being chewed when the animal died). I've read of these in a number of books, and they certainly suggest a sudden shift of climate. I've also read other books which have traced out the "ice age" glaciations which neatly fit with a pattern of movement of the polar region in relation to the continents. This book is one of the seminal sources cited by many of these others, and yet ... this is only peripherally about that. Hapgood did not believe in continental drift (which, I take it, has been pretty much solidly accepted and understood in the half century since this book was first released), and sought an alternative theory to explain various phenomena. Perhaps one of the things that gives his theorizing so much weight is that he managed to get Albert Einstein to write a foreword to the first edition ... and while Einstein isn't "on board" with everything, he pretty much says "interesting stuff, should be researched". At the core of Hapgood's theory here is the concept that as ice builds up at the poles, the weight is "spun" towards the equator and causes crustal shifting and distortion, with volcanism, etc. resulting.
One of the most glaring "errors" here is his view of the Hawaiian islands. He keeps going back to them as an "anomaly", suggesting that the mass of these huge mountains should be distorting the crust under them. Needless to say, within the context of continental drift, it's clear that these were created by the Pacific plate moving over a "hot spot" with upwelling lava, building up each of the islands in the chain as it went. It was almost humorous to see him trying to calculate solutions to fit these with his theory.
Again, perhaps my expectations were misguided (I had really hoped that this would have discussed the previously-mentioned "pole shifts" resulting in the historic pattern of glaciation), but this book is more about an alternative theory to continental drift than being about movements of the pole. Given that Hapgood's underlying theories were incorrect, it's difficult to figure out what might be of use here. I've had numerous discussions with folks who totally reject polar shifting (for various physical reasons), but there are many things which would be "best explained" by this theory. Unfortunately, that's not what Hapgood was concerned with here.
The fact that Hapgood was not a PhD, and that his specialty was history and not science, come up from time to time in this. There are whole areas not approached here (such as the frequent flipping of the magnetic poles) which a specialist would have spent a considerable time with, and there is so much here that anybody who watches the science channels on cable TV would "know better" about, that it is frequently uncomfortable reading.
Still, there are some fascinating bits in this. Hapgood implies that South America has only very recently been "raised", with the area of Lake Titicaca (now at 12,500ft elevation) having at one point been at sea level, and tracing out "fossil shorelines" which indicate that the region is at a definite incline to the original water level. If one is to take the "conservative" estimates of the Tiwanaku (whose "harbor" features are currently fairly removed from the lake) ruins, this would mean that much of the uplift in the are has only been in the past 2,500 years (of course, these are "mainstream" dates for that culture, and not the "mystical" dates which would push that site into a far more ancient context).
Anyway, The Path of the Pole goes a long way to prove what is unlikely to be provable, and is more embarrassing than interesting for most of it. While it has elements of the stuff I was hoping to read in it, they are incidental to Hapgood's main premise, a premise which is evidently incorrect. If you're still interested in it, it's still in print, and you might as well get it via Amazon (which has it for a discount, and available bundled with the far more satisfying Maps of the Ancient Sea Kings at just over the "free shipping" line). Frankly, I could have skipped this one, as it was a rather substantial read for a very minor pay-off.