Fact Gusher. This is one of those history/ anthropology books that gives a LOT of facts very rapidly, without any real critical examination of the central thesis. For a book showing *how* asphalt has been used throughout human history, it is quite good – O’Reilly shows from the earliest human records that we have been using asphalt pretty much since we’ve been using anything else, including its critical role in Egyptian mummification and even Noah’s Ark. For a book trying to make a case of *why* asphalt has been used so extensively… again, it never really examines the central thesis or really makes any kind of solid case here. Which is why I had to deduct a star. Indeed, many of the areas O’Reilly claims that asphalt was a driving factor can be more easily – and completely – explained with factors other than this particular material. Without negating that this particular tool was indeed useful and in at least some cases genuinely necessary for the execution of the events as history records them happening. Still, a truly fascinating read showing the far longer history and much more varied uses of this substance that many modern readers hardly give a second thought. Very much recommended.