There one could see the “perpetuum mobile,” one million peas, a model of Tsiolkovsky’s starship, seven hundred seven digits of pi, and even museum’s own meridian. Contrary to the classical museum rule, everything in the House of Entertaining Science could and should be touched with hands. The inscriptions used to invite: “Touch it.” Besides, Scientific Director of the unique museum Yakov Isidorovich Perelman recommended the employees complaining that the visitors were breaking the exhibits to make the latter “hand-resistant” and be happy that children were inquisitive. Perelman died of hunger during the Siege. And there is no House of Entertaining Science now, unfortunately. If it existed, maybe the new generation would choose knowledge rather than Pepsi.