In 1895, the physicist Wilhelm Röntgen discovered x-rays, a groundbreaking moment in medical history that would lead to myriad improvements to people's health. Perhaps one overlooked benefit though was in relation to mental health, specifically of those tasked with making alphabet books. What did they do before X-rays? Xylophones, which have also been a popular choice through the twentieth century to today, are mysteriously absent in older works. Perhaps explained by the fact that, although around for millennia, the instrument didn't gain popularity in the West (with the name of "xylophone") until the early twentieth century. So to what solutions did our industrious publishers turn?
As a figure of note, you might hope it would be your epic deeds accomplished that would lead to your name being uttered by students for millennia to come — not for the coincidence of the tricky letter with which your name began. But so it was for the Persian king Xerxes, who in the field of nineteenth-century alphabet books achieved what he could never quite achieve in fifth-century BC Athens, that is, domination. Though there was perhaps some small solace in that he was likely the very first historical figure of which many a child would learn.
The conveniently named XX ale makes a few appearances too. No-one's totally sure from where this unusual name stems, but possibly it was originally more akin to a crucifix and marked on the barrels by the monks to indicate that — swearing on oath — the batch was sound. It may also just simply have been an indicator of strength.