Until the cakes started to fly, the two artists were something of a mutual admiration society.

Thea Proctor was elegant, tasteful and generous, while Margaret Preston was flamboyant and stubbornly single-minded. One painted ladies on fans, the other preferred bottlebrush and banksia. But temperament and subject matter aside, they had much in common. Both were in their forties; each had spent many years abroad, soaking up techniques in the cultural capitals of Europe; both were well-known exponents of modernism, albeit in feminised forms.

Australia, Proctor declared, should be grateful to Preston for having rescued its wildflowers from the "rut of disgrace". Preston rendered Proctor's teapot in oils and showed her the mysteries of Japanese-style woodblock prints.

They first met in Sydney in the early '20s, recent expatriates fired with a desire to awaken Australia to the innovations they had encountered abroad. Instrumental in founding the Contemporary Group, they collaborated on articles and illustrations for Home, a decor magazine for the nation's more modish ladies. And although Proctor urged Australian artists to seek their place in the international modernist movement, whereas Preston advocated a national approach based on native vegetation and Aboriginal motifs, both were regarded as pushing the boundaries of Australian art.

The pairing reached its apogee in 1925, when the two held joint exhibitions in Melbourne and Sydney. Public reaction was gratifying but the big public galleries were slow to extend their recognition. If the starchy trustees of the Art Gallery of New South Wales were impressed enough to buy their work, it would be a victory for modernism and a feather in their individual chapeaux.

Proctor's studio shared the same George Street building as the Grosvenor Galleries, and they invited friends to join them there for tea after the opening. Margaret arrived bearing a box of cakes, asking immediately if the trustees had been and, if so, what they bought. Somewhat abashed, Thea was forced to admit that the grand arbiters had indeed decided to acquire a picture, and it was one of hers.

At this news, Margaret spat the dummy. She flung the cakes at Thea, turned on her heels, stormed out and disappeared "like Mephistopheles in a puff of smoke".

The careers of both artists continued to flourish, if not their friendship. In 1938, Proctor did not even mention Preston in an article on Sydney's outstanding modernist artists, except to say: "Mrs Preston's work is already widely known." To this day, postcards of Preston prints are consistent sellers in the gift shop of the Art Gallery of New South Wales.