I would like to introduce two items from this collection, or rather two collections our host has brought together, whose cohabitation here prompted me to consider whether they are related and whether the relation can be traced in a history of drawing.
The first (chronologically) is a collection of mineral samples arranged by John Ruskin (1819–1900) and donated by him to St. David’s School, Reigate, in 1883, with a printed catalogue. 
The second is a printed portfolio by John Hejduk (1929–2001), published by The Cooper Union School of Art and Architecture in New York in 1969. The ‘Three Projects’ of the title are known as ‘The Diamond Projects’ and are dated 1963–67. 
Whereas Ruskin and Hejduk both have respectable claims to a place in the history of architecture, those stones of Ruskin’s and these diamonds of Hejduk’s don’t obviously qualify for a collection of drawings. The collector of drawings is usually, and here also for the most part, a collector of autographs. These aren’t autographs. Some of the stones of the first set are cut and polished, they are labelled, but not inscribed, except by the forces of nature. The second set are lithographs, in this case not inscribed stones, but mechanical reproductions of mechanical-looking drawings.
Nor is it obvious what the two collections have to do with architecture, despite the reputations and institutional status of the two men. Hejduk’s and Ruskin’s interests were not confined to architecture and neither Ruskin’s cabinet nor Hejduk’s three projects had any consequence in the world of building. Given their different contexts, the pedagogical aims the two collections don’t necessarily bring them closer to one another or much closer to drawing or architecture.
We could suggest what Ruskin and Hejduk might have in common: the wish for a broader cultural and moral engagement than the disciplined practice of architecture or art criticism would allow; a wish for the authority, indeed the heroism, of genius; an affection for myth and mystery; a certain bewilderment and isolation. Yet, despite what the men may have had in common a century apart, the two collections, side by side, show their divergence.
Ruskin, one may say, was a naturalist and there is evidence for this in his approach to drawing and to mineralogy. A life-long amateur mineralogist and collector, Ruskin found in minerals models of geological structure and natural form. Observation of the natural forms of rocks and crystals provided Ruskin with material for a moral pedagogy that is no less present in his lectures to learned societies than in his homilies intended for children.
Hejduk, one may say, was an idealist and he displayed in his ‘Diamond Thesis’ (as he called this publication) a commitment to abstraction that was at that time mediated by his reception of the post-cubist avant-gardes of the inter-war period in Europe. In his introduction to the projects, Hejduk refers to several leading protagonists of the avant-garde: the painters Piet Mondrian and Theo van Doesburg, founders of De Stijl and co-promoters of neoplasticism before van Doesburg struck out on his own with elementarism; Charles-Édouard Jeanneret, best known as Le Corbusier, who, with the painter Amedée Ozenfant, promoted purism through their organ L’ésprit nouveau; and Ludwig Mies van der Rohe, the architect once associated with the Bauhaus, and one of several prominent refugees who enjoyed influential careers in the United States as designers and teachers following the dissolution of the school in Germany.
The Diamond Thesis concerns itself explicitly, in Hejduk’s words, with ‘certain essences’, ‘basic relationships’ and ‘generating principles’ which he identifies with quasi-geometric ‘problems’ that the earlier modernist avant-gardes had advertised along with their rejection of perspective in painting (a polemic mainly directed at impressionism), and with the implicit notion of technical drawing as a model of rational structure and ideal form.
Before tracing these divergent trajectories back to where they cross, let’s look a bit closer at the two collections and restore them to their original contexts.