The Dead Sea Scrolls, it is not. The ark of the covenant, not particularly. But the discovery of a dusty old ledger book in the Texas Panhandle may shed some light on the ancient—well, old school—origins of Dr Pepper.

The late-19th century book of drugstore formulas includes one for “D Peppers Pepsin Bitters,” which is a bitter digestive drink. The book appears to come from the same Waco drugstore where the prune-esque pop we currently know and tolerate was born, so is this a clue to the soda’s secret recipe?

According to AP, “ingredients seem to include mandrake root, sweet flag root, and syrup.” That—it seems safe to hazard—would not be a delicious beverage with which to wash down a Taco Bell Seven-Layer Burrito.

See more articles