Very far. In 1891, Walter Hines Page writes the following letter of acceptance for an article for the Forum:
My dear Sir:
I thank you for submitting your interesting paper on “Europe’s Military Frankenstein,” which I shall be glad to use in an early number of The Forum. I shall ask you to accept our check for the sum we usually pay per article — $75, which is not a large sum, to-be-sure. We shall be able to give you, however, the most appreciative audience reached, we think, by any periodical.
$75—“not a large sum, to-be-sure”—is, wait for it… $1796.34 in 2010 dollars. The letter doesn’t say how long the article was, but I’d guess not more than 2 or 3 thousand words.
ETA: Page follows up with a check for $100 ($2395.12) instead of $75, because he “could not find a paragraph that [he] could suggest [the author] to leave out. What, after all, are a few pages more or less, when you have an interesting paper?”
Citation: MS Am 1090 (1039), Houghton Library, Harvard University