<p>In <a href="http://www.edwardtufte.com/tufte/books_vdqi"><em>The Visual Display of Quantitative Information</em></a>,
Edward Tufte calls <a href="http://www.edwardtufte.com/tufte/minard">Minard’s graphic of Napoleon in Russia</a> one of the “best statistical drawings ever created.” But what makes it so good?</p>

<p>Before we analyze this graphic, we need to know a bit of history…</p>

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