If it comes to deciding between a long hot shower and a long hot bath, I always choose the long hot bath, bccause who can read in the shower? With the weather cold and windy, I drew a hot bath - we're still using our tankwater but should we ever run out, we simply turn on the newly-connected townwater - and immersed myself in the warm water and Daniel Kehlmann's "Measuring the World" --- again! because it holds so much information that one reading isn't enough.
The book recreates the parallel but contrasting lives of two geniuses of the German Enlightenment, the naturalist and explorer Alexander von Humboldt and the mathematician and physicist Carl Friedrich Gauss who, towards the end of the 18th century, set out to measure the world. It was also made into a great movie, but I've yet to dare to bring the DVD-player into the bathroom, so the book will have to do.
What I remember most from the movie is the above scene of young Gauss - pronounced, by the way, like "house" but with a 'G' - not because he was born in my home town but because he solved the tedious mathematical task, set by his teacher Büttner, of adding up all the numbers from one to one hundred not in hours but in three minutes.
It reminds me of how we were trained before mechanical machines, let alone computer devices, had become available: USE YOUR BRAIN! Our mathematics teacher called them "Rechenvorteile", perhaps best translated as "mathematical shortcuts". Want to know how many years it will take to double your money at any given rate of compound interest? Divide the rate of interest into the number 72! It's approximate but good enough for a quick answer. Cannot balance your books? If the difference is divisible by 9, chances are it's a transposition error.
More than sixty years later, these and a dozen other "Rechenvorteile" are still imprinted on my brain as are the multiplication tables and my teacher's brilliant method to put them there. Thanks to his teaching, I have balanced many sets of books in my long career as an accountant, and thanks to him, I have also doubled my money many times over.
