Serious sundials are serious instruments.
The first serious instruments of mankind, and they endured for three millennia, well into the 20th century, as the bedrock of timekeeping.

They are deceptive in their apparent simplicity but they are far from simple in their theory and their significance, thus they are the essence of beauty and elegance; blending science, esthetics; astronomy, the universe, and the ingeniousness of mankind into a seemingly simple instrument with no moving parts which, if you understand what it is telling you, it tells you a heck of a lot.

This is the one book to own on how sundials really work, not on how to make a rainy day project for a bored child or wood or metal worker but what is at the essence of the serious instrument for serious timekeeping and observations.

Though we now think of sundials as quaint garden ornaments, for at least three millennia sundials were our bedrock basis of keeping time, the foundation of astronomy, and fundamental to our understanding of the relationship of our Earth to the heavens. Even the concept of time itself, which is a slippery subject when you dig into it, began with sundials. They are A REALLY BIG DEAL if you are into such things. This book is the best available on the subject.

BUT to really fully grasp the sundial you need to know about the celestial sphere model and how the heavens work. Unfortunately this sea captain's explanations on this subject, although complete and correct, are very difficult to follow. He strives to be succinct, and if you already know what he is talking about (which he clearly does) he achieves his goal... but if you don't you will be more than a little lost. Even his representation of the "Equation of Time" is muddled with two representations of the EoT that do not equate algebraically being presented in as many lines, but frankly the EoT is muddled almost everywhere because there is no accepted standard for which way around to state it.

However if you study up on the celestial sphere model and maybe even delve into a little celestial navigation, which is a kindred spirit to the sundial and a subject on which a multitude of good references abound, this book will take you the rest of the way.

Beware. This isn't for the faint of heart. This book is about celestial mechanics (though an older model,) history, and man's development of concepts of time. It isn't a how-to project book or a fun Sunday afternoon read. It is the serious science of sundials. You will be introduced to the celestial sphere, declination, sidereal time, hour angles, right ascension, equinoxes, solstices, precession, and all that stuff. If that sounds like a fun read to you then this is a Great Book!

While the contents of the book are good, this edition in kindle (currently August, 2014) is rather ugly.
Some formulae are written as text, but others are only scanned and the text size is very small. Figures are also scanned.
The main problem arise in the main text: there are a lot of typos. The text seems scanned and procesed by an OCR so producing many typos. For example a year is printed (tSo6) while I figure out the original is (1506).

loved it

Great for designing a local sundial. Also a good reference book.

This book describes every type of sundial imaginable. Some of the math involved is formidable, but measuring time by the sun --and the moon, surprise, surprise-- formed the basis of our civilization.

Lots of info for the person looking for info on sundials.

All is Ok

Purchased this book as a gift for my husband who is interested in the history of sundials and has one he wants to repaint.