Jonathan Swift wrote about something we might consider a computer in the early 18th century, in Gulliver's Travels - https://en.wikipedia.org/wiki/The_Engine

The idea of knowledge machines was not necessarily common, but it was by no means unheard of by the mid 18th century, there were adding machines and other mechanical computation, even leaving aside our field's direct antecedents in Babbage and Lovelace.