1850-1899: Golden Age of data graphics

I've been looking at the data for my books and there seems to be a definte pattern with the increase in the use of tables in the 2nd edition of the encyclopaedia. I started wondering if there is something to this, some historical context, when lo a and behold, I find a website with Milestones in the History of Thematic Cartography, Statistical Graphics, and Data Visualization. The time period I'm looking at was considered the "Golden Age of Data Graphics."

Thank you very much Michael Friendly and Daniel J. Denis. For putting together a most useful resource.

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