As it was a clear night, the detectives had no trouble to see that the man who joined Mason was a negro.
And then they recognized him as Sim Johnson, the valet.
For a few moments the pair held a whispered conversation, and then climbed down the piles and got into the rowboat.
Creeping nearer, the Bradys now caught a good view of the boatman.
He was a little old man, in a blue blouse and felt hat, and his face was covered by a gray beard.
When Mason and the negro were aboard, the boatman rowed out on the river, shipped his oars and let the skiff drift with the tide.
The Bradys reached the end of the pier and watched them keenly.
There was something towing behind the skiff by a rope.
As the skiff paused, the three men pulled it into the boat.
It was a large object, but the detectives could not make out at that distance what it really was.