Gordon - As we have crossed northern France we have noticed significant changes in the architecture of houses and public edifices. Some of this is dictated by the availability of materials (brick in Pas de Calais versus stone in areas further east), some reflects history (everything in the Somme region was built in the 1920's after being leveled in World War I), but some just appears to reflect local taste. For example, we passed through an area where exposed timber, bearing a resemblance to Tudor style, was popular. There was another region where many buildings had root cellars with beautiful stone frames for the access doors. Most unexpected of the local preferences, however, are the roof tiles on churches in the Franche Comte region, which we recently entered. The tiles appear to be glazed, come in a variety of bright colours, and are often arranged in complex, repeating patterns. The roof of the cathedral in Langres has a pattern that resembles the machine readable ikons that have become common. I can imagine extraterrestrials flying over the cathedral and reading the code as "Christian house of worship", or perhaps "take home a family pack of tasty carbon based life forms today".