This is a very attractive book to pick up, because it's richly illustrated with period illustrations (mostly engravings and patent diagrams) of old inventions. And reading it offers many moments of interest, especially in Part I of the book, where John Lienhard (JL) discusses the ambiguous notion of priority of inventorship, i.e., who was the first to invent something. But the whole doesn't quite stick together.
The book was written when JL was already an emeritus professor. The choice of topics jumps around -- the priority theme is shifted somewhat in part II, which focuses on "steam and speed", then gets blurred even more in Part III, on the rise of texts and scientific illustration, before returning in the last chapter. This structure, together with JL's many personal reminiscences, makes it feels like a rather relaxed amble through miscellaneous topics and themes that intrugued JL during the years, rather than a tightly-structured argument. Not that some of the ambles and rambles aren't interesting -- I especially enjoyed learning about early flying machines and how the Wright Brothers pitched their propellers, and an anecdote JL tells in the last chapter about dropping a glass rod makes a very nice practical point about the relationship between mathematical models and reality.
However, I was frustrated by some other aspects of the book. Most of the historical topics, such as the history of printing technology and its social impact, are far better-treated in other books. A three-page mini-history of computing (@159-162) lapsed into the same teleological narrative that JL is at pains to criticize elsewhere in the book; e.g., he claims that the idea of "creating a machine to execute a string of instructions ... appeared not to have crossed anyone's mind until Charles Babbage proposed it in 1834" (@159), thereby ignoring centuries of music boxes and other automata dating back to the time of Archimedes.
Also, some of the scientific explanations, especially in Part II, were so rushed-through that I found them hard to understand even when I had some familiarity with the subject. Lots of diagrams, such as of Watt's steam engine, are labelled with letters indicating their components, but JL almost never refers to these, leaving it to the reader to figure out which thingamajig most looks like what JL is describing. Or consider this passage, from a description of the connection between atoms and thermodynamics (making the point that the 18th Century's phlogiston theory wasn't so crazy):
"Every molecule is held together by powerful electronic forces. It requires energy to pull those atoms apart. If we burn carbon in oxygen, we dismantle the O2 molecules to form two atoms of oxygen. Then those two atoms combine with one carbon atom to form carbon dioxide, CO2. Since it takes more energy to pull CO2 apart than it does O2, the net effect of burning carbon in oxygen is to *release* energy." (@75; emphasis in the original.)
I re-read this several times before I realized that JL skipped mentioning that the combination of a carbon atom with 2 oxygen atoms to make CO2 releases energy -- and specifically, more energy than what's needed for breaking up oxygen molecules. But that fact is an empirical one, not a matter of logical necessity; omitting to mention it just leaves the attentive reader scratching his or her head in puzzlement.
All told, the book feels midway between an agglomeration and a synthesis, like a cake that needs about another 20 minutes in the oven. I'd have liked JL to have followed up on some his most intriguing observations, e.g. the implications for the patent system of his comments about fuzzy priority, and the notion of "invented qualities", which appears only in a throwaway remark at the end of a chapter (@115; JL mentions speed, efficiency and accuracy as examples). Maybe this is too much to expect. But a proper bibliography is not. The book exemplifies an unfortunate trend of discourtesy to readers (perhaps on the part of the Oxford U Press, not JL) by including only footnotes but no comprehensive list of references. For this I deduct an additional 1/4-star from the 4 stars for the rest of book, net 3.75 stars.