Matthew Arnold’s pivotal year was 1851. It was the year his personal mission as a poet was most glaringly at variance with his public obligations and with the spirit of the age.

It was the year of the Great Exhibition, but while the Crystal Palace glittered, announcing Britain’s greatness to the world, Arnold wrote the melancholy “Dover Beach”, a hymn to confusion, doubt and the dwindling of faith. As Ian Hamilton remarks in this sensitive biography of Arnold as a poet: “Arnold not only felt out of tune with the age; he also felt out of tune with his own work - which he could see was neither celebratory nor even very helpful.” Arnold’s gift was all diagnosis and no cure.

In the same year Tennyson published In Memoriam, a work of such commanding genius that other poets quaked. This was particularly true of Arnold, so frequently criticised as a poet. Unlike Tennyson he was not born to the art, and created his verse with steady effort.

Arnold had long been obsessed with the idea of being a full-time poet, but another task called. He had just married and felt himself obliged to earn a living which could keep a family. He became an inspector of nonconformist elementary schools which took pupils between the ages of four and nine and enjoyed a state subsidy which put them in line for government inspection.

Arnold was responsible for Lancashire, the Midlands, East Anglia and parts of Wales and the West Country, a territory so vast he had to undertake almost constant travel. He found himself “too utterly tired to write” and was dismayed by the passage of time and his low achievement. “How life rushes away - and youth,” he wrote. “One has dawdled and scrupled and fiddle-faddled - and it is all over.”

He found inspiration in the work of teachers who, he felt, must prefer to be anywhere but school yet made the best of it. “I saw the cheerfulness and efficiency with which they did their work... Gradually it grew into a habit with me to put myself in their places.”

The best he was hoping for, realistically, was early retirement. Artistically, he came to feel that poetry which might supply “religious wants” had been achieved, and what was now required was not more poetry but more awareness of what poetry could offer - better criticism, in other words.

Hamilton writes of how Arnold’s sense of duty wore away at his verse until his poetic career was over by the age of 40, but few poets produce much of value in later life. While it is interesting to read the remarks of another poet on Arnold, and Hamilton’s criticism is sharp and just, the sense remains that this is a commonplace story of a man reaching middle age to find that the “heat and radiance” of creative gifts which had flourished in youth are withering.

Jad Adams’s ‘The Dynasty: the Nehru-Gandhi Story’ (with Phillip Whitehead) is published by Penguin