What Made the Depression 'Great'?

With the early 1930s currently being invoked on an hourly basis, I've been meaning to refresh my memory as to the nature of that particular crisis. Unfortunately, I'm absolutely dismal when it comes to this particular science--I almost failed econ in high school, and the semester I spent auditing a macroeconomics seminar in graduate school didn't provide any evidence of improvement. The only stuff I can understand comes from Robert Heilbroner. Fortunately, this piece in yesterday's NYT spells out some of the similarities--and dissimilarities--in bite-sized chunks.