He thought of Sam Stay's offer.
It came in a flash to Tarling that the man who had thrown the bottle of vitriol at him, who had said he had kept it for years--was Sam Stay.
Stay, with his scheme for blasting the woman who, he believed, had humiliated his beloved patron.
And now for Milburgh, the last link in the chain.
Tarling had arranged for the superintendent in charge of the Cannon Row Police Station to notify him if any news came through.

The inspector's message did not arrive, and Tarling went down through Whitehall to hear the latest intelligence at first hand.

That was to be precious little.

As he was talking there arrived on the scene an agitated driver, the proprietor of a taxicab which had been lost.

An ordinary case such as come the way of the London police almost every day.