'Dodseds!' he snapped, with the irritation of a man whose proverb has been capped by another. I had seldom heard him speak so sharply. White's revelation had evidently impressed him. He had all the ordinary peaceful man's reverence for the professional detective.

'White will accompany you, Bister Burds,' he said doggedly.

'Very well,' I said.

After all, it might be that I should get an opportunity of giving him the slip. London is a large city.

A few minutes later the cab arrived, and White and I set forth on our mission.

We did not talk much in the cab. I was too busy with my thoughts to volunteer remarks, and White, apparently, had meditations of his own to occupy him.

It was when we had settled ourselves in an empty compartment and the train had started that he found speech. I had provided myself with a book as a barrier against conversation, and began at once to make a pretence of reading, but he broke through my defences.

'Interesting book, Mr Burns?'

'Very,' I said.

'Life's more interesting than books.'