National Proofreading Day (8 March), as you may have guessed, “promotes mistake-free writing” – an aspiration as old as the written word. Medieval manuscripts are full of errors and amendments by scribes and copyists, as well as marginal comments such as “New parchment, bad ink; I say nothing more” and “That’s a hard page and a weary work to read it.”

With the invention of movable type, it soon became clear that documents needed to be checked after setting. However, it is not clear when proofreading emerged as a separate role. According to the 1911 edition of Encyclopaedia Britannica: “The first products of the printing-press show abundant evidences of the non-existence of any one specially charged with the duty of correcting the compositors’ mistakes. How much conjectural emendation and consequent controversy would have been avoided if the First Folio Shakespeare had been more typographically correct!”

Early editions of the Bible were famous for typographical errors, though it is suggested that the most notorious – “Thou shalt commit adultery” instead of “Thou shalt not commit adultery” – was the result of a conspiracy rather than a misprint. Once this version of the 7th Commandment had been spotted, a year after its 1631 publication, the royal printers Robert Barker and Martin Lucas were fined £300, their printing licence was removed and the print run of 1,000 was recalled. Not every copy of the Wicked or Sinners’ Bible, as it became known, was destroyed, however, and as recently as November 2015 a copy came up for auction at Bonhams in London, selling for over £30,000. According to Bonhams’ website: “It has also been suggested that the mistake was an act of sabotage, possibly perpetrated by Barker’s rival Bonham Norton, to politically embarrass Barker. Certainly the controversy added to Barker’s decline in fortunes and reputation, and he was in and out of the King’s Bench Prison before dying there in 1645.”

If you’re interested in biblical typos, the International Society of Bible Collectors has compiled a handy list (Curiosities in Bible Editions).

In the 17th and 18th centuries, the usual practice was for the author to be responsible for proofreading, often passing the proofs on to friends to read. With the expansion of publishing came a demand for something more reliable and the major printing presses used scholars and leading men of letters to read for them. Irish playwright, poet, novelist and journalist Oliver Goldsmith is thought to have been a proofreader at one time, as was Dr Johnson. One of said men of letters, Isaac D’Israeli (father of Benjamin), wrote: “It became the glory of the learned to be correctors of the press to eminent printers.”

Proofreaders have had some famous friends over the years. This is from Charles Dickens:

“I know from some slight practical experience what the duties of correctors of the press are, and … I can testify … that they are not mere matters of manipulation and routine; but that they require from those who perform them much natural intelligence, much superadded cultivation, considerable readiness of reference, quickness of resource, an excellent memory and a clear understanding. And I must gratefully acknowledge that I have never gone through the sheets of any book I have written without having had presented to me … some unquestionable indication that I had been closely followed in my work by a patient and trained mind, and not merely by a skilful eye. In this declaration I have not the slightest doubt that the great body of my brother and sister writers would, as a plain act of justice, heartily concur.”

Inevitably, not all Dickens’s brother and sister writers did concur. Before the Accuracy Matters team gets too excited about “natural intelligence” and so on, here is Mark Twain on proofreaders:

“Yesterday [my publisher] wrote that the printer’s proof-reader was improving my punctuation for me, & I telegraphed orders to have him shot without giving him time to pray.”

“In the first place God made idiots. This was for practice. Then he made proof-readers.”

And here is a timely warning from the wonderful Mary Norris, a long-term copy-editor at and contributor to The New Yorker and author of Between You & Me: Confessions of a Comma Queen:

“Muphry’s Law: If you write anything criticising editing or proofreading, there will be a fault of some kind in what you have written.”