In a newsletter from Paris, William D. Cohan reports on the city's record heat, noting Tuesday was the country's hottest day on record with temperatures regularly topping 100 degrees. The main business event is a check-in with Bitcoin evangelist Michael Saylor, as the reference cryptocurrency has fallen by more than half since peaking at $126,000 in October. Additionally, the SpaceX I.P.O. is having a rough go, currently trading at around $155, down more than 40 percent from its peak of $225 a share last week, though still above the I.P.O. price of $135 per share. Monday’s decline in the SpaceX stock—down 16.4 percent—cost Elon Musk $152 billion, or about as much as Bernard Arnault’s entire net worth.