Today, Erh knows that art deco, the nearly 100-year-old style that arrived in Shanghai from Paris along with large-scale western investment in the treaty port, was strongly inspired by Chinese and Japanese aesthetics. In Shanghai, art deco returned to its eastern roots, and was refined and elaborated. 'I call it Shanghai art deco,' says Erh.

To celebrate Shanghai art deco, Erh recently collaborated on a book of the same name with Shanghai-based writer, conservationist and retired American diplomat Tess Johnston, with whom he has worked on other books about the city's cosmopolitan past. Erh photographed scores of buildings, and the pair devote a large section of the book to the relatively neglected subject of art deco furniture, household objects, magazines and advertising.

Long scorned by the Communist Party as a symbol of Shanghai's decadent, western past, art deco is enjoying a revival on the mainland. In the hopes of reaching a domestic readership, the book is written in English and Chinese.

The style epitomised the spirit of pre-war Shanghai. A city built by three nations - China, France and Britain - Shanghai was aggressively modern and international. Its architecture was proud and optimistic. Built to last, the city's high-rises sported soaring geometric patterns. Lines, curves and zigzags represented the dynamism of the new industrial age, but the bold designs were softened by rounded forms and attractive floral and arboreal detailing. And in a new twist, Chinese motifs such as clouds, mountains over waves, Taoist octagrams and coins became popular, and many interiors were covered in marble and gold leaf.

Shanghai's art deco was only superficially western and was a leap forward for Chinese architecture and design. Key examples are the Peace Hotel, which is about to be renovated, the Embankment Building and the Morriss Estate.

'Chinese designers could do the western designs very well, and then they gave them a twist - for example, these characters,' say Erh, pointing to elongated, geometrical lettering on a journal called Creativity and Criticism. 'They have an art deco flavour and they are utterly Chinese.'

Working in Paris after the first world war, French designers such as Pierre Legrain and Jacques-Emile Ruhlmann copied eastern designs to incorporate geometrical patterns, simplicity of form and the key principle that form should follow function.

A generation of Shanghai-born architects embraced the movement. From well-off families, they were well versed in classical Chinese culture and graduates of prestigious western universities. Erh's fascination with these architects has led him to start research for a book on their leading lights, such as Robert Fan (Fan Wenzhao) and Poy G. Lee (Li Jinpei), who were among dozens who learned their trade at the Princeton University School of Architecture in New Jersey.

Many of the buildings they designed are still standing today, including the Majestic, Paramount, Metropole and Empire theatres, the Young Brothers Bank and the Continental Emporium. The Majestic, by Fan, had a sweeping staircase and severe, flowing lines until a recent refurbishment concealed most of its striking lobby behind a neoclassical marble facade and columns.

The China Aviation Association building, whimsically shaped like an aeroplane, was designed by Dayu Doon (Dong Dayu) and was part of the ruling Kuomintang's Greater Shanghai plan for architecture, cut short by the Japanese invasion in 1937.

'What they were doing was creating real architecture for the Chinese themselves,' says Erh. 'Not like today - it's just a mess what people are doing.'

In 1935, in perhaps the apogee of the local deco style, Chinese Architect magazine announced that three bold, vertical lines on the exterior of Empire Mansions - built by foreign architect Kyetay - represented Sun Yat-sen's three central principles of nationalism, democracy and people's livelihood.

Other major architectural firms included Britain's Palmer & Turner, Hungarian architect Ladislaus Hudec and French firm Leonard, Veysseyre & Kruze.

Art deco furniture, too, was already an east-west amalgam by the time it arrived in Shanghai. Frenchmen such as Jean Dunand were inspired by Chinese and Japanese aesthetics, which were simple in form but rich in design. They revived East Asian techniques such as using crushed eggshells, ivory and other delicate inlays.

Shanghai craftsmen copied designs and added carved details such as clouds and waves in woods rarely used in the west, such as teak and mahogany.

Erh owns scores of pieces, which he kept in a private museum until two years ago, when officials closed it down. They offered just a five-figure sum in compensation. 'Enough to buy just one chair today,' says Erh.

'When it comes to culture, the government still wants to control things really tightly, so they're happy to build big, official museums, but they don't want to let private people build their own,' he says.

His furniture collection, featured in the book, is in storage near Hongqiao airport.

The teacups, teapots, snuff and perfume bottles, refrigerators and electric kettles in his collection all feature a mixture of bold, geometric shapes with rounded floral and fruit motifs in typically bright deco colours such as pink, green, mauve, olive and yellow.

Some, such as a popular cologne bottle shaped like an ear of corn, were in production in Shanghai until after the Cultural Revolution. 'After 1949, they produced very few new products. So things like cologne bottles, they just kept producing until the end of the Cultural Revolution.'

'For these kinds of products, the influence on the lives of Shanghainese was very broad. Everyone used them.'