Carel Visser is considered to be the most important Dutch sculptor since World War II. The starting points of his work are natural motifs from visible reality, that he interprets in an abstract formal vocabulary. Until the end of the 1970s Carel Visser mainly worked in iron, creating works that are variations on a limited number of themes, like stacking, rotating, reflecting and linking of similar forms.

The welded iron sculptures Carel Visser made during the 1950s, gained him national and international recognition. He started this period with subtle animal forms which later on would transform into robust abstract constructions, like the present lot.

Double form 6 is part of a series of six abstract sculptures. Blotkamp writes about these pieces: 'By far the most important symmetrical works date from the second half of 1957 and the following year: a series of six works collectively titled Double form. Visser started on these when he returned home from Italy, where he had done a great many nature studies, among them one of a rocky island and its reflection in the water. [Hans] Locher correctly connected the Double form with these works. The mirror effect which he used in the studies of islands recurs in woodcuts and a number of particulary good pencil drawings done in 1957 and 1958. The drawings employ exclusively geometrical shapes, horizontal or vertical bars, in greyish tone, or occasionally in yellow, so that they suggest the subtle tones of a seascape.

In formal terms however, the Double form can also be seen as rigorous abstraction of Two birds (1954). Each piece is constructed of two 'birds', consisting of a flat block with smaller flat protuberances on four sides. They mirror each other with respect to an imaginary horizontal axix of symmetry. In spite of these shared characteristics, there is a striking degree of variation within the series. Never before had Visser so thoroughly exploited the possibilities offered by a particular sculptural donné'.