'Friday I tasted life,' Emily Dickinson once wrote, 'A circus passed the house - still I feel the red in my mind though the drums are out.' Kenneth Koch by contrast is more of a ringmaster than a peeper-out from behind curtains, taking his cue - along with his exclamation mark and the cumbersome enthusiasm of his line - from Whitman: 'With what pomp and ceremony the circus arrived orange and red in the dawn!'. Despite its panache, this early manner (dating from the 50s) doesn't quite convince. Fernand Leger lived in the same apartment block as the young Koch, and surrealism at that stage of his career was on a hair-trigger. Circuses are surreal enough, with their elephant men and red giraffe managers, but Koch gives us Minnie the Rabbit as well, a Disney character gone feral, toting a gun which fires woollen bullets. Aileen the trapeze artist comes a cropper by falling from her high wire; somewhere on the wild side - but surely it is the circus itself which should function as the wild side? - Minnie expires in parallel.

Excess - especially of the comic sort - is a healthy vice at the outset of a career, and in any case it is the delight of this generous selection that we can watch the poet develop, and monitor his own development. He produces his self-portrait in a convex mirror, or rather in a whole broken bundle of mirrors, the features shrinking and ballooning ...