Only with the technological advances of the past few years has a book such as this become possible. Kent Larson of the Massachusetts Institute of Technology (MIT) has created computer visualisations of several major unbuilt projects by Louis Kahn, and they are startling in their verisimilitude.
The schemes are all from Kahn's maturity, postdating the decisive months that he spent in Rome in 1950-51 (which included his fiftieth birthday). As architect in residence at the American Academy there, he was not just profoundly affected by Roman remains, but by other encounters with the monumental on travels to Egypt and Greece. Those experiences inform these unrealized works: the US Consulate in Luanda; the Salk Institute Meeting House; Mikveh Israel Synagogue; Hurva Synagogue (three variants); the Memorial to Jewish Martyrs; and the Palazzo dei Congressi, Venice.
'Somehow the Pantheon was seeping into everything he did, ' said Peter Smithson in an AJ issue on Kahn (4. 3. 92). The impact of the Pantheon, particularly in its play of light, direct and diffused, is a major theme of this book; and it is closely linked to another - Kahn's comment in an interview of 1961 on designing for a country of brilliant light. 'I thought of wrapping ruins around buildings; you might say encasing a building in a ruin so that you look through the wall which has its apertures as if by accident. I felt this would be an answer to the glare problem. '
Wrapping ruins around buildings became a refrain, not just at the latitude of Luanda but in Philadelphia, where Mikveh Israel would have stood. At Luanda, where detached segments of wall with keyhole arched openings act as a fragmentary screen, the strategy is still tentative. From the Salk Meeting House onwards, however, the ruins are not just planar but threedimensional, and (as Vincent Scully says in his introduction) Kahn not only deals with glare but increasingly seeks to create 'luminous interior space'.
This is seen most of all in the unbuilt schemes that best suit the book's title of 'masterworks'- the two synagogues; though both have their unresolved problems. At Mikveh Israel cylindrical concrete towers around the perimeter of the building, with glazed openings on their exterior and unglazed ones within, diffuse the light entering the sanctuary, roofed by a shallow inverted dome. The towers recall Kahn's sketches of Carcassonne and Scottish castles, but no extant drawing by Kahn conveys the likely illumination of the interior so well as Larson's computer images. They help one sense a grave and numinous space.
With the Hurva Synagogue in the Old City of Jerusalem, intended as the central monument of the new Jewish state, Kahn's quasi-ruins would have been in a context of real ones - religious buildings destroyed in the 1948 war. The last major book on Kahn, In the Realm of Architecture, which accompanied the touring exhibition in the early 1990s, only treated this project briefly, so Larson's thorough presentation of the three proposals is of real value. With the monumental pylon-like structures that flank the building in all three variants, we see Kahn looking beyond Rome to the architecture of Egyptian temples. Here, as at Mikveh Israel, it is questions of glazing that were never altogether resolved.
Larson takes the schemes in chronological order. With the first, Luanda, he supplies a resume of Kahn's development as well as a description of the building so text and image are out of sync; otherwise his exposition and analysis are neatly integrated with the images - plans and sections, Kahn's drawings and, above all, the computer visualisations.
These are uncanny in so convincingly depicting materials, textures and the fall of light. In an afterword, William Mitchell of MIT explains how such photorealistic rendering is now feasible on computer. The main challenge has been to capture 'the extraordinarily complicated interreflections of light from surface to surface'. Thanks to 'raytracing and radiosity procedures'(whatever they are), this book can have the accuracy it does.
'A lot has happened in architecture since Kahn died, ' says Scully. 'But all of it makes Kahn's work look better than ever on its own terms, better in its solidity, its gravity. 'Therein lies the only reservation about this book. Its beautiful illusions are a reminder that, precisely because of that solidity, Kahn is one of those architects whose projects are least susceptible to two-dimensional reproduction. His work is emphatically visceral, not just optical, and its reality impinges when shafts of light are not transfixed, as in Larson's images, but waver with a passing cloud.
Only in that sense, though, is this book a disappointment as well as a delight.