Boxes' model. The purpose is to assemble boxes in the ascension. These plasters build isolation and darkness, both are the feelings of Chloé in L'écume des jours. Here is the first test of the objective by putting smaller box on a bigger one. It would be now a narrow corridor without light in the dark basement of L'Aula des Cèdres in Lausanne.
Ladder's test. Experimentation of a second way to climb from one slab to another.