Next moment I had slipped from my hiding-place and was lounging along at a respectable distance behind them.

How I regretted that I had had no time to hail Rayner, for he would have had no difficulty in keeping observation upon the pair, while I, at any moment, might be recognized by the cunning, clever old fellow to whose inventiveness all the coups of the notorious Jules Jeanjean were due.

He seemed to walk more erect, and with more sprightliness, than at Cromer, where his advanced age and slight infirmity were undoubtedly assumed. In his present garb he really looked what he was supposed to be—a wealthy dealer in gems.

Engaged in earnest conversation, Gregory and his companion walked together along the dark road until they came to a taxi-stand near the station, when, entering the first cab, they drove rapidly away.

The moment they had left, I leapt into the next cab and, telling the driver to keep his friend in sight, we were soon moving along after the red tail-light of the first taxi.

The chase was an exciting one, for we whizzed along dark roads, quite unfamiliar to me, roads lying to the south of Ealing towards the Thames. My driver believed me to be a detective from my garb, and I did not discourage the belief.

Suddenly we turned to the right, when I recognized that we were in the long, narrow town of Brentford, and travelling in the direction of Syon House, the main road to Hounslow and Staines. At Spring Grove, which I had known slightly in years gone by, we turned again to the right, and were soon passing through a district of market-gardens and solitary houses.

On the way I had leaned out of the window and instructed the taxi-driver to keep well behind the other cab, so as not to be discovered. Therefore, in carrying out my orders, he suddenly put on his brakes and stopped, saying—

"They're going into that house yonder, sir. See?"

I nipped out quickly and saw that in the distance the other taxi had pulled up and the two men had alighted before a garden gate.