The motor lacked the smooth purr of the van.

A few moments later they heard the smooth purr of the Mustang pulling out of the driveway.

"Dropped in to see you," returned the stranger, his voice a smooth purr that did not fit his expression.

With a smooth purr, the twin cylinders spun into action.

Overhead an electric lamp burned, and from somewhere nearby came the smooth purr of a generator.

If only Wyler would say more, in that smooth purr of his!

A smooth purr came from the front of the house.

The steady, smooth purr of the dynamo in the power room makes us wish we too, were machines.

Shooting up into the branches, they didn't hear the limousine's starter, nor the smooth purr of the big car's motor.

His voice took on a smooth purr.