A youngster inhales the air from a balloon for a few seconds and sits on the ground with a smile. He experiences "a tingling" feeling, a "shiver" and a sense of "well-being", he explains, which lasts for half a minute. The air inside the balloon is nitrous oxide, which is better known as laughing gas. It is not a new drug, because tourists who come to Catalonia, especially French and British, have been using it for years, also in Barcelona.

Whether it was because it was a Sunday, because the subway closed at midnight or because people were just too hungover, the fact is last night of La Mercè festival has been the quietest of all. The firework display put an end to a festival that will be remembered for the mass illegal parties, two of which were very eventful: the one on Friday night at the Plaça Espanya and the one on Saturday night at Bogatell beach. Yet Sunday night was a lot calmer.

Barcelona's end-of-summer festival, La Mercè, appears as a new litmus test on the way out of the pandemic. As we have seen lately, there have been obstacles: uncontrolled outdoor parties, known as botellones, have proliferated as bars and clubs have remained closed. Restrictions on nightlife will be eased on Thursday for premises which have outdoor spaces, which are very few. Therefore, the possibility of mass botellones remains, with the resulting public order problems (noise, damage to furniture, dirt, homophobic violence...) and danger of contagion. In this final stretch of summer and the beginning of autumn, the sustained advance of vaccination (by the way, what a disaster that 70,000 doses have expired: on the one hand, there must have been some kind of lack of foresight, and on the other, irresponsibility among youngsters) has created a partly false feeling that the virus has been defeated. Covid is in retreat, but it is still there, even if it can't do as much damage. But we are a long way from no longer needing to worry.