“The Speck that Changed the World” should perhaps have taken precedence over the dot itself in terms of the purported subject matter: Humez & Humez meander all the way around a cornucopia (a horn of plenty, as you will learn if you read On the Dot) of subjects and disciplines related to, but not strictly or immediately about the dot as it exists in written communication throughout the entirety of the book.
As far as information about the dot goes, if you’re looking for a pretty purely historical retelling of the story of the dot in academic style, this is probably not going to cut it. However. If you’re in the mood for sauntering along in a manner much like a flâneur might, then this dense stream of consciousness will surely charm and delight you!