The Berlin Hitler destroyed

"I don't write witty columns. I paint the portrait of the age," the journalist and novelist Joseph Roth once protested to his editor. Roth was the poet of Berlin streetlife in the 1920s, a "botaniser on asphalt", fascinated and appalled by what he found. Berlin was crowded, vibrant and sordid; the capital of government and of the arts but also a sink into which the worst problems of the Weimar Republic were draining. Roth moved round the city cataloguing its oddity with an unsentimental eye, in the slums of the Jewish quarter, in the homeless hostels, in department stores, dives, parks and at the races. Even more than his admirer Isherwood, Roth was a camera.

It gives some idea of the sophistication of Weimar culture that these philosophical, challenging and often fantastical pieces of writing by Roth (wonderfully translated by the poet Michael Hofmann) were originally newspaper columns. Roth was not a native Berliner, but was mesmerised by the city, especially its futuristic technology and architecture.

There was mystery and romance for him in skyscrapers, "life-creating warmth" in the railway junction, a magic-carpet quality about the electric S-Bahn train. The only ugly things in this concrete-and-steel wonderland were its inhabitants: the tart in the night club, whom he watches drinking up leftovers, the photos of unidentified corpses in the police station, the spluttering nationalist sounding off in the barber's shop. Degeneracy is merely human, Roth says, the "logical brain" will put its faith "in a body of unconditional certainty: in the body of a machine".

Roth's love of recording the minutiae of everyday life makes this book often read like a brilliant existentialist novel: "What I see hasn't made it into the Baedeker", he says on one of his walks along the Kurfurstendamm; "What I see is the sudden, unexpected and wholly meaningless rising and falling of a swarm of mosquitoes over a tree trunk. The silhouette of a man laden with firewood on a forest path. The eager profile of a spray of jasmine tumbling over a wall."

He isn't being poetical here - or not very. Roth theorises about everything but never moralises. One of the most characteristic pieces in the book is The Resurrection, a vignette about what it must be like for a prisoner recently-released into modern-day Berlin after a 51-year sentence.

It is a parable of the impact of environment on people but also an exercise in sympathetic imagination which slides into the present tense at its vivid, unresolved ending.

One section of this book is titled An Apolitical Observer, but Roth was far from that; his writings from the 1920s emphasise the fragility of Berlin's grip on itself and the pervasiveness of anti-Semitism.

When Hitler came to power, Roth went into exile in Paris and the last essay in the book, written from France in 1933, abruptly reverses his earlier mode of speculative, essentially leisured observation. It expresses outrage at the persecution of Jews, disgust at the resurgence of "Prussian superiority" as a stick with which to beat the cosmopolitan nature of the German republic and bitterness at the inevitability of books being burned under the leadership of a man (Hindenburg) whose boast was that he had never read one.

It's an amazing unleashing of Roth's powers of argument, an onslaught of straight talking after all the oblique ironies of the earlier "feuilletons": "The European mind is capitulating. It is capitulating out of weakness, out of sloth, out of apathy, out of lack of imagination". But of course, by 1933, this was already too late.