Josip Plecknik: An Architect of Prague Castle.

In a hall near the entrance to Prague Castle is a wall fountain consisting of a lion's head above a strange granite bowl. And below the lion is carved a single word: SEMPER. Latin, for 'always'? Possibly. But it could well be a pun: a tribute to Gottfried Semper by his most inventive and resourceful disciple, Joze Plecnik, the architect of Prague Castle in the 1920s.

The Lion Fountain is the frontispiece to Damjan Prelovsek's study of the Slovenian master, first published in German in 1992 and now at last translated into English. This is appropriate as Prelovsek insists on Plecnik's debt to the great German architectural theorist. Semper's cladding theory, that architecture evolved from structures hung with textiles, certainly explains many of the inspired, strange transformations of Classical forms achieved by Otto Wagner's brilliant pupil. And that weird external treatment of his great church in Prague: perhaps those stone blocks proud of purple brickwork represent ermine, fit to clothe the Sacred Heart of Jesus, King of Bohemia.

Over the last two decades, Plecnik has slowly but steadily re-emerged as one of the giants of the twentieth century, perhaps the most creative of all those who might be said to belong to the alternative tradition to the Modern Movement. His work in Vienna, Prague and his native Slovenia is extraordinarily rich, inventive and resonant, and surely of increasing relevance to contemporary practice. And the literature is now growing, but this beautifully illustrated study by Prelovsek - grandson of Plecnik's Ljubljana client and friend must be the best: the most perceptive, illuminating and authoritative.

Damjan Prelovsek was adviser to the exhibition, 'Josip Plecnik: Architecture for the New Democracy', held in Prague Castle last summer (AR August 1996). That was, I think, the best architectural exhibition I have ever seen, for it combined archival material with an exploration of the actual spaces and structures Plecnik created for Tomas Masaryk, President of the new Czecho-Slovakia, in which he made a supreme demonstration of how it is possible to be truly original while working in harmony with historic buildings.

Now an English version of the book of the exhibition has appeared, published by the Prague Castle Administration. It is sumptuous and immensely covetable; many of Plecnik's exquisite drawings for his beautifully crafted interventions are illustrated, together with superb photographs, and there are essays exploring the range, meaning and influence of Plecnik's achievement. And, for some reason, there is one by Kenneth Frampton, who tells us that he was 'an architect of this century and hence by definition modern', and that his work is 'oneiric'. That means dream-like. You will not, of course, find Plecnik mentioned in Mr Frampton's own books on the architecture of this century, but at least the record is now being put straight.