“To gaze at an invisible Eclipse on the first of April”

In the 1730s Benjamin Franklin printed John Jerman’s American Almanack several times even as he was establishing his own Poor Richard’s Almanack.

Franklin had a habit of ribbing his rivals through the voice of Richard Saunders, his almanac-making pseudonym. Specifically, “Saunders” suggested Jerman was about to turn Catholic, which even in Philadelphia was suspicious.

Eventually Jerman chose to work with different printer, telling readers that Franklin had maligned him. “Saunders” responded in his almanac for 1744:

My Adversary J--n J----n has indeed made an Attempt to outshine me, by pretending to penetrate a Year deeper into Futurity; and giving his Readers gratis in his Almanack for 1743 an Eclipse of the Year 1744, to be beforehand with me: His Words are, “The first Day of April next Year 1744, there will be a great Eclipse of the Sun; it begins about an Hour before Sunset. It being in the Sign Aries, the House of Mars, and in the 7th, shows Heat, Difference and Animosities between Persons of the highest Rank and Quality,” &c.

I am very glad, for the Sake of these Persons of Rank and Quality, that there is no manner of Truth in this Prediction: They may, if they please, live in Love and Peace. And I caution his Readers (they are but few, indeed, and so the Matter’s the less) not to give themselves any Trouble about observing this imaginary Great Eclipse; for they may stare till they’re blind without seeing the least Sign of it. . . .

I leave him to settle the Affair with the Buyers of his Almanack as well as he can, who perhaps will not take it very kindly, that he has done what in him lay (by sending them out to gaze at an invisible Eclipse on the first of April) to make April Fools of them all.

I’ve found lots of quotations and some discussions of this passage, but I haven’t found confirmation that Jerman indeed made such a prediction. According to a N.A.S.A. website, there was no eclipse on that date, and that would have been an unusual mistake for an experienced astronomer.

Of course, Jerman might have been making an April Fool’s joke that “Saunders” insisted on taking literally. Or “Saunders” could have made the whole thing up, the same way he made up the stuff about Jerman becoming Catholic.