About five o'clock in the evening, just as the negotiations were broken off, M.Aubry, an artillery captain who had been sent with two hundred men to the depot of field artillery in the country, returned with six pieces of ordnance, determined to make a breach in the tower occupied by the conspirators, and from which they were firing in safety at the soldiers, who had no cover.

At six o'clock, the guns being mounted, their thunder began, first drowning the noise of the musketry and then silencing it altogether; for the cannon balls did their work quickly, and before long the tower threatened to fall.
Thereupon the electoral commissioners ordered the firing to cease for a moment, in the hope that now the danger had become so imminent the leaders would accept the conditions which they had refused one hour before; and not desiring to drive them to desperation, the commissioners advanced again down College Street, preceded by a bugler, and the captains were once more summoned to a parley.

Froment and Descombiez came out to meet them, and seeing the condition of the tower, they agreed to lay down their arms and send them for the palace, while they themselves would proceed to the Electoral Assembly and place themselves under its protection.

These proposals being accepted, the commissioners waved their hats as a sign that the treaty was concluded.
At that instant three shots were fired from the ramparts, and cries of "Treachery! treachery!" were heard on every side.

The Catholic chiefs returned to the tower, while the Protestants, believing that the commissioners were being assassinated, reopened the cannonade; but finding that it took too long to complete the breach, ladders were brought, the walls scaled, and the towers carried by assault.