Sometimes he drew him close to the windows of a passing carriage, that he might see its master's face by the light of the lamps; and, both in respect of people and localities, he showed so much acquaintance with everything around, that it was plain he had often studied there before; as indeed, when they grew a little more confidential, he confessed he had.
Perhaps the most striking part of all this was, the number of people--never in groups of more than two or three together--who seemed to be skulking about the crowd for the same purpose.

To the greater part of these, a slight nod or a look from Hugh's companion was sufficient greeting; but, now and then, some man would come and stand beside him in the throng, and, without turning his head or appearing to communicate with him, would say a word or two in a low voice, which he would answer in the same cautious manner.

Then they would part, like strangers.

Some of these men often reappeared again unexpectedly in the crowd close to Hugh, and, as they passed by, pressed his hand, or looked him sternly in the face; but they never spoke to him, nor he to them; no, not a word.
It was remarkable, too, that whenever they happened to stand where there was any press of people, and Hugh chanced to be looking downward, he was sure to see an arm stretched out--under his own perhaps, or perhaps across him--which thrust some paper into the hand or pocket of a bystander, and was so suddenly withdrawn that it was impossible to tell from whom it came; nor could he see in any face, on glancing quickly round, the least confusion or surprise.

They often trod upon a paper like the one he carried in his breast, but his companion whispered him not to touch it or to take it up,--not even to look towards it,--so there they let them lie, and passed on.
When they had paraded the street and all the avenues of the building in this manner for near two hours, they turned away, and his friend asked him what he thought of what he had seen, and whether he was prepared for a good hot piece of work if it should come to that.