Customer Reviews

Measure for Measure: The Story of Imperial, Metric, and Other Units

5 star:		(3)
4 star:		(0)
3 star:		(2)
2 star:		(1)
1 star:		(0)

 

 

I was not the best student in high school or college, but now that I'm a "mature grownup" I enjoy reading science journals and books - as long as they're not too dry or massive. Who has time to plow through a 600 page tome?

I enjoyed reading Measure for Measure. Mr. Hebra uses lively text, formulas and plenty of clear drawings to help explain the subject matter. In every chapter I found fascinating details. Like how close we came to adopting a metric clock (10 hours per day, 100 minutes per hour) or that the great Thomas Edison electrocuted stray dogs to prove how dangerous AC electricity was, compared to DC. Yikes!

As with all disputes, the opposing sides of the metric vs. "standard" debate can sometimes be very polarizing and shrill. Mr. Hebra does not try to sway us one way or another but instead explains the logic and history behind our systems of measurement. He sometimes strays off the subject, but that's part of this book's charm. Hebra's anecdotes are amusing and help put a human face on the evolution of science and measuring systems.

If you want to learn a little more about and how mass, size, heat and time are all related and measured I strongly recommend picking up a copy of Measure for Measure.

The great science myth is that all scientists use metric units. In this marvelous little book, which is thoroughly enjoyable to read, Hebra shows that they don't. Astronomers have parsecs, particle physicists use barns, and engineers and mathematicians often don't use units at all. To prove his point, Hebra shows us how to instruct space aliens to build a hydroelectric dam, without knowing what fluids they may use, how big their planet may be, how strong its gravitational force may be, etc.

Along the way, there are some fascinating anecdotes about hogsheads and jereboams, the thirteen-month year proposed by the League of Nations, and the size of Noah's ark.

I now have a far greater appreciation of the scientists and engineers who struggled so hard, and for so long, to come up with a standard system of units. I wish I could have read this book when I was taking physics in college. It's entertaining and breathes life into the science of measurement.

I just love books like this. They guide the reader through various physical concepts using simple calculations, often to arrive at interesting conclusions. The author of this book has attempted to do this in an accessible way while mixing in historical snippets to add to ones reading pleasure. Unfortunately, I must agree with the prior reviewer who commented on the fact that the book was very poorly edited. There are, indeed, too many errors and typos, especially in the equations, and many explanations lack the clarity and completeness that one would expect in such a book - things that may discourage neophytes and induce feelings of impatience and mistrust in the minds of the initiated. But because of the interesting topics discussed, a thorough, proper and careful revision of this book, including careful re-thinking and re-writing of some of the discussions would easily make it five-star material. Such a revised version would be an asset to popular science literature.

Alex Hebra takes us on a nimble romp through dozens of scientific and technical subjects. He strikes a nice balance of historical background and modern understanding. Cleverly executed sketches illustrate many of the concepts.

Unfortunately, this book desperately needs better proofreading, editing for grammar and sentence construction, fact checking, footnotes, and, most of all, a major reorganization. Frequent typos in the equations as well as the text will confuse neophytes and discourage knowledgeable readers from trusting the rest of the information. Inductive reasoning and speculation take the place of documented logic in too many places. The author's desire for reader-friendly style occasionally produces frivolous, flippant, or irrelevant treatment of important concepts.

A few examples of problems with organization and content: Extensive introductory discussion about the nature of measures and units, including dimensionless quantities, appears only in the last few chapters, after the reader has struggled through a welter of chaotic chatter about miscellaneous technologies. Cryogenics is dismissed in 76 words, the history of typesetting in 27, while two silly anecdotes about Enrico Fermi occupy an entire page. The Newton appears on page 62, but is not defined until page 141. The nautical mile, introduced on page 41, is quantified on page 162. Newton's Cradle, the multiple steel ball pendulum device that perfectly illustrates conservation of momentum and kinetic energy, is nicely pictured but sadly neglected in the text. The desirability of standardizing on the SI system is mentioned numerous times, but receives no convincing justification. The recent confusion of units leading to the loss of a Mars Lander, a golden opportunity to emphasize the importance of consistency, is not discussed in any detail.

Corrections to some of the factual errors: Spy satellites have low orbits, not geosynchronous. The weightlessness of objects in Earth orbit is not due to the reduction in gravity as a function of distance from the Earth. Apparent magnitude of the star Arcturus was promoted over that of Vega on the basis of modern photometric measurements, not because of any increase in atmospheric pollution. The essence of the sport of highjumping lies in raising the body's center of gravity, not "jump above own head." The "Vomit Comet" subjects passengers to zero gravity, not high g-forces (the highest it gets during entry and exit from its arc is about 1.8 g's). Fire pumps ignite tinder with a single motion, not repeated cycles. Reaching absolute zero is impossible because doing so would violate the Third Law of Thermodynamics, not because "it would take infinite energy." An electric heater employing alternating current has no net flow of electrons through its circuit. Life on Earth began more than 2 billion years ago, not 600 million.

This book covers a lot of information which could be done quite interestingly. However, its organization leaves so much to be desired that I was very disappointed in the book. It covers things like dimensional analysis and the effect of choice of units on physical formulas, as well as the history of units (as promised in the title), but it jumps from topic to topic in a chaotic manner, with topics that are closely related scattered among different chapters and things that ought to be separated lumped together in one chapter.

Another reviewer talked of the errors in some of the equations in this book. They are there, but I don't think that this is the biggest problem with this book. Rather, it is the totally incomprehensible lack of any sensible organization.

Measure For Measure is an informed and scholarly history of imperial, metric and other units of measurements blends science, engineering, and human discovery in a historical survey which examines standards of length and mass. Different systems are juxtaposed and examined during the course of Hebra's coverage, providing an excellent, engaging survey of past, present and possible future measurement systems and how they came to be.