My granddaughter and I paused before Turner’s

‘War: the Exile and the Rock Limpet’

in the collection of the artist’s work

at Tate Britain, Millbank, beside the Thames.

The exile is Napoleon Bonaparte

on St Helena. He stands – in signature

outfit including the hat – arms folded,

contemplating obscure life in a rock pool.

A guard, musket shouldered, stands some paces off.

The sun rises or sets on a swirling, volcanic coast.

‘Was Napoleon really that tall?’ she asked.

‘Good point,’ I said. ‘I too thought he was short.’

We left the Tate by the Manton entrance.

I pointed out the many shrapnel gouges

blitzed deep into the limestone facade

from discarded bombs meant for the docks downstream,

and told her how Rothenstein, the curator,

and his wife had slept for months on camp beds

to act as early air raid wardens.

Later I googled Rothenstein – no mention

of wife never mind kipping on a camp bed.

In fact he had arranged for works to be moved

to, for instance, Cumbria and the Marches

after the Molotov-Ribbentrop Pact,

more than a week before war was declared.

I made a mental note to correct

the anecdote with my granddaughter –

and I realised suddenly that

Napoleon would have seemed very tall

from the perspective of a rock limpet.