“I had engaged with four pupils to go to Orleans in this Long Vacation:  my brother William was also to go.  One of my pupils, Dobbs, did not join:  the other three were Tinkler, Ogilby, and Ibbotson.  We left London on July 9th, and travelled by Brighton, Dieppe, Rouen, and Paris to Orleans.  At Paris I saw Bouvard, Pouillet, Laplace and Arago.  I had introductions from Mr Peacock, Mr South, Mr Herschel, Dr Young; and from Professor Sedgwick to an English resident, Mr Underwood.  On the 19th I was established in the house of M. Lagarde, Protestant Minister.  Here I received my pupils.  On the 28th I commenced Italian with an Italian master:  perhaps I might have done more prudently in adhering to French, for I made no great progress.  On Aug. 2nd I saw a murderer guillotined in the Place Martroi.  The principal investigations on my quires are—­Investigations about pendulums, Calculus of Variations, Notes for the Figure of the Earth (Encyc.  Metrop.) and commencement of the article, steam-engine machinery, &c.  I picked up various French ballads, read various books, got copies of the Marseillaise (this I was obliged to obtain rather secretly, as the legitimist power under Charles X. was then at its height) and other music, and particulars of farm wages for Whewell and R. Jones.  The summer was intensely hot, and I believe that the heat and the work in Dolcoath had weakened me a good deal.  The family was the old clergyman, his wife, his daughter, and finally his son.  We lived together very amicably.  My brother lodged in a Cafe in the Place Martroi; the others in different families.  I left Orleans on Sept. 30th for Paris.  Here I attended the Institut, and was present at one of Ampere’s Lectures.  I arrived at Cambridge on Oct. 14th.

“On Oct. 16th Whewell mentioned to me that the Lucasian Professorship would be immediately vacated by Turton, and encouraged me to compete for it.  Shortly afterwards Mr Higman mentioned the Professorship, and Joshua King (of Queens’) spoke on the restriction which prevented College tutors or Assistant tutors from holding the office.  About this time Mr Peacock rendered me a very important service.  As the emolument of the Lucasian Professorship was only L99, and that of the Assistant Tutorship L150, I had determined to withdraw from the candidature.  But Mr Peacock represented to me the advantage of position which would be gained by obtaining the Professorship (which I then instantly saw), and I continued to be a candidate.  I wrote letters to the Heads of Colleges (the electors) and canvassed them personally.  Only Dr Davy, the Master of Caius College, at once promised me his vote.  Dr French, Master of Jesus College, was a candidate; and several of the Heads had promised him their votes.  Mr Babbage, the third candidate, threatened legal proceedings, and Dr French withdrew.  The course was now open for Mr Babbage and me.

“In the meetings of the Philosophical Society a new mode of proceeding was introduced this term.  To enliven the meetings, private members were requested to give oral lectures.  Mine was the second, I think, and I took for subject The Machinery of the Steam Engines in the Cornish mines, and especially of the Pumping Engines and Pumps.  It made an excellent lecture:  the subjects were at that time undescribed in books, and unknown to engineers in general out of Cornwall.