"Hidden Numerical Forces" by Thomas Henry
Suggested Retail USD$35.00
Available direct from Leaping Lizards Magic
In a Blink: 10 Out of 10

"Hidden Numerical Forces", a book by Thomas Henry, is a collection of mathematical principles which can be used as forces... without looking like forces. That's a tall order, but Thomas Henry does it expertly.

I have to say that when my publisher, Leaping Lizards Magic, contacted me about reviewing "Hidden Numerical Forces", I was skeptical. Very skeptical. Look, the last thing the world of magic needs is another collection of self-working math tricks. We don't really need to break out a calculator, go through a huge number of mathematical operations to arrive at a single digit, which was "predicted" ahead of time.

So I was skeptical. That's my job.

On the back of Thomas Henry's book, it says "Prepare to be surprised." I was.

"Hidden Numerical Forces" is not what I was expecting. It's not a collection of dried out, worn thin, presentationally silly math tricks. It's an encyclopedic, thorough look at mathematical principles which can be used as forces without appearing to be forces at all. That makes this book gold.

If Henry had settled for throwing number tricks together, this book would have been hopeless. Instead, Henry dives into the mathematical principles and then shows how to take those principles and make them presentationally sound.

And that's probably what I love most about this book. Yes, there are tricks here and there, showing how to use the forces to their potential, but more than that Henry concentrates on educating the reader enough that the general principles behind the forces become tools for our own creations. All the while, Henry takes great pains to make sure that, in addition to understanding the principle at work, we also get all the little things, the subtleties and the nuances, that disguise the principles and make magic.

So what principles are we talking about? Some common and some not-so-common (if not unknown) things are placed under Henry's microscope. You'll find his thoughts on the old 1089 force (his thinking here blew me away and had me thinking about breaking that chestnut out again), the 9 force, and even the oft-exposed but still valuable 37/68 force. Yep, tried and true and usually spurned because they appear to be so mathematical in nature, but Henry's thinking on these classics breathes a bit of new life into them.

The lesser known stuff gets the same treatment, and wonderfully so. Henry explains using a matrix force, a transpose force, and even a topological force. While more challenging mathematically, Henry makes their use simple for the performer and magical for the spectator.

That last sentence sums up this book perfectly. That was Henry's stated goal, after all, to put together a book of math principles which, when wrapped up within an appropriate presentation, allow for great magic to happen.

Henry did that in "Hidden Numerical Forces", and did it beautifully.

"Hidden Numeric Forces" by Thomas Henry
In A Blink: 10 Out of 10

Material: 10
Henry has written what amounts to a thesis on numerical forces. Far more than just tricks with numbers, Henry goes into great detail on working with and creating forces that work mathematically and magically.

Quality: 10
Henry's writing is incredibly thorough, mathematically and historically. A deep read at times, which is to be expected given the subject matter, Henry's writing style makes the material nonetheless easy to understand and use.

Illustrations: 10
Illustrations, mostly line drawings and diagrams, work perfectly with the text and really make learning some of the principles much easier.

Presentation: 10
This is what it's all about: making numerical forces look like anything other than numerical forces. Henry succeeds with that task, hands down.

Shane