The balloon seller's roof

An original literary non-fiction-style account of passing a balloon seller in a covered market.

The balloons made a second ceiling beneath the market roof. Red fish pressed against silver stars; a yellow horse leaned over a row of smiling faces. Their strings fell into the seller's hand like a bundle of pale roots. He stood below this crowded garden wearing a coat almost exactly the colour of the pavement.

Whenever someone passed too close, the whole collection shivered. A star turned edgeways and became unexpectedly thin. The horse lost its confident profile, showing a crumpled seam beneath its chin. Then the shapes settled, glossy and complete again. From the far end of the aisle, they had looked much more certain of themselves.

A child stopped beside the stall and pointed upwards. The seller lowered the yellow horse slowly through the other balloons. For a moment, the fish and stars seemed to make way for it. The child took hold of the string, but the horse turned towards the roof as soon as the seller released his hand. The child's arm rose after it. Her mother tied the string securely to a handle on the pushchair.

As they left, the horse travelled above the crowd, visible long after its new owner disappeared between coats and shopping bags. The seller closed his fingers around the remaining strings. A little space had opened in the second ceiling, too small to notice unless you had been watching. He shifted his hand, and a silver star slid across to fill it.

How does the writer use language to convey the balloons' appearance and their movement among people?