Statistical Atlas of the United States, Based Upon the Results of the Eleventh Census (1890) - plate 36: Composition of the foreign-born population: 1890
The pattern
This still is filed under Data as proof.
Define
A chart, map, or count that is the argument, not an illustration next to the argument.
Mechanism
Sighted evidence. The reader is asked to believe their eyes: a bar, a share, a spread on a map.
Verdict
The claim is comparative or quantitative and the figure can be read without a caption doing the sell.
Why it works
Holding the diameter constant strips out the size variable on purpose, so the eye is forced to read mix and nothing else, and the plate becomes a pure comparison rather than a ranking. Laying the panels out in rough geographic order lets regional blocks surface as visual texture without a map: the New England row goes grey and green for Canada and Ireland, the upper Midwest row goes blue for Scandinavia, the border row goes blank for other countries. Near black is assigned to Germany, the largest group, so the single most important fact is the highest contrast mark on the sheet. Putting the key once at the foot rather than beside every panel keeps forty-nine charts free of repeated labelling.
Steal this when
Use this when you have one metric split the same way across many units, markets, branches, cohorts, and the question is which units resemble each other rather than which is largest. Fix the panel size, order the panels by something meaningful like geography or tenure, and give the dominant category the darkest ink.