My friend Cosma came to Oxford to give a talk, so I spent Sunday afternoon showing him around town.
One highlight was stumbling over the components of a prototype of the original Babbage Difference Engine in the Museum of the History of Science. I must have visited the MHS half a dozen times without ever noticing these - they are in the upstairs room on the bottom shelf of one of the three-tiered display cabinets on the far right as you go in. They're not that impressive to look at, but given what they represent I'm surprised the Museum doesn't have them showcased more prominently. (They do feature in a MHS episode of Sydney Padua's "Thrilling Adventures of Lovelace and Babbage".)
We also looked at Blackwells (our first stop, for a coffee fix), the Pitt-Rivers museum and Merton College. And despite having had to buy a second bag to hold all the books he'd bought on Charing Cross Rd the day before, Cosma found room for five more from the Last Bookshop. He's a bibliophile after my own heart.
Cosma's seminar on Monday was based on his paper on "Homophily, Contagion, Confounding: Pick Any Three". I'd read this before, but it's a nice result and the presentation was lively, with entertaining audience questions (they included one sociology grad student saying something along the lines of "but this means what we're trying to do is impossible, should we just kill ourselves now"). I should definitely go to more seminars.
Update: Cosma has posted about his visit.