(ISBN 1 870232 12 7)
Unashamedly a child of 'Energy Plants and Man', 'Like Clockwork' (save for the occasional borrowed illustration) was, when first published, an entirely new concept in Portable Document Format (PDF).
A Review in 'New Scientist' (13th January 2001 No2273) said "Like Clockwork does for photosynthesis what A Brief History of Time does for theoretical physics: it takes a baffling but fundamental process and makes it easy to understand. David Alan Walker uses the electronic book format to explain the transfer of energy from sunlight with lots of clear, colourful diagrams and relevant links."
In 'Trends in Plant Science' John Allen wrote "Like Clockwork is not concise, it is discursive. An unkind epithet might be 'rambling'. Of course a rambler will see, and understand, much more than someone racing through a prescribed itinerary. And what, as David Walker himself might write, is wrong with that? Like Clockwork is thought provoking. It is also fun. And, in spite of David Walker's major and lasting contributions in photosynthesis research, there are still open questions, and a humility that leaves room for the reader to form his own opinions. David Walker is about as far as can be from saying 'because I say so'. Science is not a list of facts, but the way we make the world intelligible. So I know which kind of book I prefer. Like Clockwork is unique, and I warmly recommend it."