Abstract: A table is composed of two superimposed horizontal plates braced by two superimposed rows of blocks forming wedges associated pairwise. Blocks of a lower row are linked to the upper face of a lower plate which is itself linked to a fixed base of the machine. Blocks of an upper row are linked to the lower face of an upper plate. The faces in contact of each pair of blocks form a fixed angle with the horizontal. Each block of each pair has an essentially semi-cylindrical shape whose generatrices are oriented transversely with respect to the direction of displacement of the movable upper plate. Each of the blocks is located in a cradle of complementary shape formed, respectively, in the upper face of the fixed lower plate and in the lower face of the movable upper plate. Structure is provded to modify and fixed at will the angular position of each block of the lower row independently of the other blocks in the same row.