Lovelace (Ada).- Lacroix (Silvestre Francois). An Elementary Treatise on the Differential and Integral Calculus, first edition in English, Ada Lovelace's copy, Cambridge, 1816.

Lovelace (Ada).- [Byron (Augusta Ada, married name Augusta Ada King, Countess of Lovelace, mathematician and computer pioneer, 1815-52)].- Lacroix (Silvestre François) An Elementary Treatise on the Differential and Integral Calculus, translated from the French [by John F.W. Herschel, Charles Babbage, & George Peacock], first edition in English, Ada Lovelace's copy with East Horsley Tower blind-stamps on front free endpaper and title and gold initials AAL at tail of spine, 5 folding engraved plates at rear, very small hole in Advertisement leaf text, a few ff. with slight staining in upper margins, some foxing and browning throughout, with 42 pages of ink and pencil corrections (mostly mathematical corrections) and including a few notes in pencil in a contemporary unidentified hand possibly by ?Ada Lovelace, contemporary half calf gilt, slightly rubbed, 8vo, Cambridge, for J. Deighton and Sons, 1816.

⁂ Ada Lovelace's copy of Babbage's first important publication, exposing English students to 'continental mathematics'. "... Charles Babbage, George Peacock and John Herschel... translated Lacroix Treatise on Calculus and touted the superiority of Leibnitz's differential notation over Newton's (then widely regarded in England as sacrosanct)." - Dictionary of Scientific Biography.

With a pencil inscription at end of the Advertisement leaf: "How vain are the affectations of Man! Four years later this book was printed." Also, seemingly random pencil note at tail of page 635, perhaps a draft of a note or letter: "You must not trouble yourself - I shall not read the one or the other - and I'll be - A?--."

Ada Byron, the only legitimate daughter of Lord Byron was solely brought up by her mother, Anne, after her parents separated. Determined that her daughter should not become a poet, she was trained as a mathematician and scientist, eventually leading to a close friendship with Charles Babbage. "In 1843 she translated a paper by General L. F. Menabrea, later to be prime minister of Italy, describing Babbage's main attempt to implement this notion, the projected analytical engine (which was to supersede the aborted difference engine but which was never built). She added extensive notes to Menabrea's paper which contain not only what is regarded as one of the earliest computer programs but also prescient comments about the future of such an engine, which have stood the test of time." (Oxford DNB). She married, in 1835, William King, eighth Baron King of Ockham, Earl of Lovelace, and they had two sons and a daughter. In she went to live in East Horsley Tower which the above books were bound.