The dataviz pioneer you’ve never heard of


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The most important person in the history of newspaper data visualization is a man you’ve never heard of.

His name is William Mitchell Gillespie. He made today’s graphic. Headlined “The Progress of Our Population,” and published in The New York Times on May 19, 1860, it is a line chart of the 1860 census, showing how the rank of populations of the states and territories changed from 1790 through 1850. It’s an early example of what today we’d call a slopegraph, encoding 181 variables across 60 years.


Smaller charts on the same page project the results of the unfinished 1860 census, and explore the demographic changes that marked the enormous growth of the country in the mid-19th century. Like many data visualizations made for newspapers around then, it's likely carved in wood, with labels made using metal type.

If anything in mid-19th century newspaper graphics can be called "common," it's Gillespie's credit line. He's cited in at least five graphics I've found from the period. He is effusively credited on the New York Tribune’s chart of cholera deaths in 1849 that I wrote about earlier this year. It’s not perfectly clear what role he played in making them, except in the case of a chart from 1854, which explicitly credits him for its construction. Most of the others claim simply to be “indebted to” him. Bylines as we know them now hadn’t been invented yet, so it’s hard to know what to make of any of that. But his contribution was big enough to merit mentioning.

While Gillespie wasn’t quite obscure, he’s a hard man to research. Here’s what I know:

He was born in New York City in 1816 and died there on New Year’s Day in 1868. He was a professor of civil engineering at Union College in Schenectady, New York. During his long career he wrote several technical books, including a translation of Auguste Comte’s writing on mathematics, and books on road building and land surveying.

He helped start the Civil Engineering department at Union College, and so appears on their website a few times, including a history of the Union College math department which sings his praises. “Gillespie not only stressed the importance of mathematics in engineering, he began a tradition of emphasizing the humanities for the engineers as well.” Hm.

He was even included among the “Literati of New York City” in a disappointingly vague article by Edgar Allen Poe, which includes such generic observations as, “The general expression of the countenance when in repose is rather unprepossessing, but animation very much alters its character.”


As a smart academic with an broad horizon, Gillespie seems to me to be a key link between William Playfair’s work and the mass media. Gillespie would have had access to Playfair’s economics books, and he was smart and literate. He would have been well positioned to understand the power of data visualization to help regular people understand large sets of data very quickly.

But I haven’t found any correspondence between Gillespie and any newspaper editors. If he exchanged letters with Horace Greeley of the New York Tribune, those letters are not in the collections of Greeley’s papers that I’ve looked at. Whatever correspondence he had with editors at the New York Times is not among the company’s papers held by the New York Public Library. And so, unfortunately, I don't know how the editors who worked with Gillespie thought about these graphics, how he sold them on the idea, or how readers reacted to them.

(Incidentally, Henry Raymond was an editor at The New York Tribune before he founded the Times. It seems likely that he, or somebody who came with him from the Tribune, was responsible for publishing these charts.)

Even Union College, where Gillespie spent 23 years as a Civil Engineering professor couldn’t offer much help, telling me they “did not appear to have much in the way of his personal papers”.

For now, our missing link is still not quite connected. I’m optimistic I’ll make a breakthrough one day. Until then, I’m probably America’s foremost expert on Prof. William M. Gillespie. It is, sadly, a particularly low bar. In the weeks to come I’ll share all of the Gillespie charts.


American Educators Deceased in 1868, The American Educational Monthly Volume 6.

Edgar Allen Poe, The Literati of New York City. Godey’s Lady’s Book, May 1846