The book covers a wide variety of scientific areas. However, it is obvious that the author (a professor of Chemistry at the Univ. of Texas) is most comfortable in the fields of chemistry and biology, and therefore chapters on discoveries in chemistry are significantly longer and in much greater detail than the rest. Although the book is meant for readers without any relevant background, some of the extensive chemistry notations in these sections can be unfathomable to the general audience, and it seems that they could have been avoided without affecting the story-telling. For chapters other than those chemistry related, the presentation is generally brief and less exciting, and much less authoritative, e.g., unnamed people or people named but with no background information, who did play a role in some of such discoveries. Thus there is an imbalance between sections of different subjects. There is also a trace of what appears to be a mixture of the author's original account and the effort perhaps by the editor in an attempt to make the material more readable. (Note an obvious typo/mistake in the first few pages; an alloy of 14-karat gold is purported to be made of "58% gold and 48% other materials" which does not add up to 100%!!)
Overall we gave the book a rating of 2.5 on a 5 point scale. The book is easy reading and could give you some nice conversation material. "Do you know how the cure for small pox was discovered?" could impress people at a dinner table and fill a pause.