Who rides the roller coaster first every morning?

Ismael climbs into car one at ten past nine, alone, helmet on, radio against his chest.

Behind him ride four water dummies, seventy-five kilos each, which is what the people who haven't arrived yet weigh.

He takes the whole loop: the climb, the whistle, the braking. He gets off, checks his watch and writes three things on the sheet.

Then he unhooks the chain at the head of the queue and steps aside to let the first real one through.