At the sound of firing in the council-room the Indians in the streets were to fall on the garrison and every British soldier was to be slain, care being taken that no Frenchman suffered.

The plan, by its treachery, and by its possibilities of slaughter and plunder, appealed to the savages; and they dispersed to make preparations for the morning of the 7th, the day chosen for carrying out the murderous scheme.
The plot was difficult to conceal.

The aid of French blacksmiths had to be sought to shorten the guns.

Moreover, the British garrison had some friends among the Indians.
Scarcely had the plot been matured when it was discussed among the French, and on the day before the intended massacre it was revealed to Gladwyn.

His informant is not certainly known.