Read it through once

“It was some time before I found out where my two gentlemen were living; but I inquired and inquired until at last I dropped across them. They were at a boarding-house at Camberwell, over on the other side of the river. When once I found them out I knew that I had them at my mercy. I had grown my beard, and there was no chance of their recognizing me. I would dog them and follow them until I saw my opportunity. I was determined that they should not escape me again.