It is proved that the inequality \( \chi (\mathbb {R}^3 \times [0,\varepsilon ]^6) \ge 10, \)holds true for an arbitrary \(\varepsilon > 0\), where \(\chi (M)\) is the chromatic number of an (infinite) graph with vertex set M, and in which two vertices are adjacent if they are at the distance 1. Bibliography: 15 titles.