From A Bibliography of Alexandre Dumas père by Frank Wild Reed: That is to say the National Guard of Saint-Germain-en-Laye, of which Dumas was commandant. He announced to them, with a characteristic flourish, the Revolution which had driven Louis-Philippe from the throne. It is dated February 27th, 1848.
The full text may be read in Lecomte's "Alexandre Dumas," pp. 189-90.
It may also be read in Fossé d'Arcosse's "Feuillets Détachés."