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Einstein for Everyone Nullarbor Press 2007 revisions 2008, 2010, 2011, 2012, 2013 Copyright 2007, 2008, 2010, 2011, 2012 John D. Norton Published by Nullarbor Press, 500 Fifth Avenue, Pittsburgh, Pennsylvania 15260 with offices in Liberty Ave., Pittsburgh, Pennsylvania, 15222
"How strange is the lot of us mortals! Each of us is here for a brief sojourn; for what purpose he knows not, though he sometimes thinks he senses it. But without deeper reflection one knows from daily life that one exists for other people -- first of all for those upon whose smiles and well-being our own happiness is wholly dependent, and then for the many, unknown to us, to whose destinies we are bound by the ties of sympathy. A hundred times every day I remind myself that my inner and outer life are based on the labors of other men, living and dead, and that I must exert myself in order to give in the same measure as I have received and am still receiving...
Nice. You may also like this. http://thinkonyourown.com/harm/WeaponMakers.html by Dec 16
Perpetual Futility A short history of the search for perpetual motion. by Donald E. Simanek Popular histories too often present perpetual motion machines as "freaks and curiosities" of engineering without telling us just how they were understood at the time.
Despite its incredibly low density, aerogel is one of the most powerful materials on the planet. It can support thousands of times its own weight, block out intense heat, cold and sound – yet it is 1,000 times less dense than glass, nearly as transparent and is composed of %99.8 air. The lowest-density silica-based aerogels are even lighter than air.