On Saint John's Day in 1826, a historic event occurred in the center of Barcelona which, despite its great significance, is not entirely known. Generally, the start of public street lighting is remembered as the moment, in 1843, when the Societat Catalana per a l’Enllumenat per Gas of Pere Gil Babot and Charles Lebon began to operate. But the reality is that a few years earlier, a solitary entrepreneur named Josep Roura Estrada illuminated a building in Barcelona for the first time using gas. The Saint John's Day we mentioned a few lines back was the date chosen by Roura to install a lighting system in the Llotja building, which was the headquarters of the Junta de Comerç school.