When I came out of work I found that they had shut Eastcastle Street and a fleet of flat bed trucks filled it, parked end to end in columns, each carrying a bulky slab of green metal. Piles of weighty concrete blocks sat between the vehicles and an impromptu fence had been constructed round the lot, pulled tightly together by heavy industrial chains. It looked like a weapons dump of an invading army.

When I walked past the next morning, much of the fence had gone and men in high-visibility jackets were fitting the pieces of green metal together like an over-sized meccano.

By lunchtime a huge green crane was raised into the sky, slabs of concrete piled high on the straining support vehicles to anchor them to the spot as the mighty construction swayed above the neighbourhood. Crowds stopped and stared, necks did their own craning to watch. A red crane lay in pieces on newly arrived trucks.

Late afternoon and the red crane had been put together and lifted onto the roof of a nearby building. Much smaller and more compact, it looked like the helpless baby bird, perched in a nest waiting to be fed by an protective parent.

Crowds watched as the green crane continued to ferry concrete slabs up to its anxious child, slotting them as a counter-weight at the rear of the red crane.

And when I arrived at the work the following morning, the green crane was gone, as were the trucks. Eastcastle Street had returned to normal. The red crane, now independent and confident was lifting materials on its own, oblivious to the world below.