This evening, the City of Geneva held a reception for those attending the conference. It was located at the Science History museum on the banks of Lac Léman (Lake Geneva). Wine (and probbaly some other drinks) and many little sandwiches were served.

One feature of the museum is that it houses some of the original
equipment from the record-setting experiment of Sturm and Colladon on Lac
Léman that measured the speed of sound in water to a much greater
degree of accuracy than before. Their motivations were not simply for the
good of science; they were attacking a prize problem set forth by the
French Académie des Sciences in Paris. The setup was clever, even
if crude by today's standards: one boat supported a large submerged bell
the would be struck at the same time as a flare was lit to signal the
start time to the other boat some 13km away. The other boat was equipped
with a timer (with a quarter-second accuracy) and a "hydrophone",
essentially a tube with a sounding chamber on the end that was held in the
water facing the sound source.