Spaces between words weren’t common until the 7th century

From the Economist:

A book seems such a simple structure that it feels less invented than self-evident, the innovations behind it hard to see. Yet every chapter in its progress was slow, bound on either side by centuries of sluggishness. Turnable pages didn’t really arrive until the first century bc; the book form didn’t take off properly until the fourth century ad. The separating of words with spaces didn’t get going until the seventh—verylateforsomethingsouseful. Finally things accelerated: first came the index, in the 13th century, then Gutenberg, then, in 1470, the first printed page number. You can still see it in a book in the Bodleian Library.