Certificate of Authenticity by Dr. Andrei B. Nakov dated June 11th, 1995. It is known that Rodchenko was interested in meteorology, cosmology, and mathematics, though there is less evidence of his interest in real construction undertaken by the professional engineer. There are several circle paintings of 1920, that certainly look like diagrams of the solar eclipse. By around 1918 the concept of pictorial ‘composition' had come to be associated by Russian ‘left' artists with the long hegemony of the European bourgeois easel painting tradition. Now, from the end of 1920 and the beginning of 1921, the final definition of the ills of that system had become a clear priority for artists within the constructivist camp. General avant-gardist enthusiasm for faktura had been able to take matters only so far. Therefore soon after the beginning of 1921, a General Working Group for Objective Analysis within the Institute of Artistic Culture (INKhUK) staged a series of vigorous debates on the distinction between ‘composition' and ‘construction', in which the very nature of drawn or spatial line proved absolutely central.