How long did Lovelace spend translating Menabrea's article?

Lovelace spent nine months translating Menabrea's article on the Analytical Engine. She worked on the translation during 1842–43, before adding a much larger set of original notes.

The article began as Luigi Federico Menabrea's French account of Babbage's 1840 Turin lecture. Charles Wheatstone asked Lovelace to translate it into English, and Babbage encouraged her to expand the work. Her additions became seven notes, labelled A through G, and were roughly three times longer than the translated article.

The most famous section, Note G, described a method for calculating Bernoulli numbers with the Analytical Engine. It is often called the first published computer program, although Babbage had also written earlier programs and historians debate how the credit should be described. The engine itself was never completed, so Lovelace's proposed program was not run on the original machine.