The servants had all fled after the arrest of the marquis and his wife, and the mob had taken possession of the house.

The lofty mirrors were smashed into fragments, the costly hangings torn down, and after they had destroyed much of the elaborate furniture, every man and woman began to lay hands upon whatever they fancied and the mansion was already stripped of the greater part of its belongings.
With his hands in his pockets, whistling carelessly, Harry wandered from room to room watching the proceedings.

Several barrels of wine had been brought up into the salon, and round these were gathered a number of already drunken men, singing, shouting, and dancing.
"Drink, drink, my garcon," a woman said, holding a silver goblet full of wine towards him, "drink confusion to the tyrants and liberty and freedom to the people." Harry drank the toast without hesitation, and then, heartsick at the destruction and ruin, wandered out again into the streets.
Knowing the anxiety which Marie would be suffering as to the safety of her lover he next took his way to the mansion of the Duke de Gisons.

The house was shut up, but groups of men were standing in the road opposite talking.
Sauntering along Harry stopped near enough to one of these to hear what they were saying.

He learned that the duke had been arrested only that morning.