Titus Livius (Livy), The History of Rome, Book 24
Frank Gardener Moore, Professor Emeritus in Columbia University, Ed.

37. Upon this revolt, feeling was aroused in other city-states, and Roman garrisons were being either driven out of citadels or betrayed by treachery and slain. [2] Henna,¹ perched on a lofty site with cliffs on every side, was not only impregnable from its position, but also had a strong garrison in its citadel and a garrison commander who was certainly no easy prey to plotters. [3] This was Lucius Pinarius, a man of high spirit and one who gave more weight to precautions against possible deception than to the honour of Sicilians. And at this time the news of so many cities betrayed and in revolt and of so many garrisons destroyed had made him more intent upon guarding against every danger. [4] Accordingly every position had been prepared and provided with guards and sentinels night and day; and the soldier did not leave his arms and his post. [5] When this was noticed by the leading men of Henna, who had already made an agreement with Himilco to betray the garrison, namely, that the Roman left no opportunity for treachery, they were forced to act openly. [6] They said that city and citadel ought to be under their own control, if as free men [p. 295]they had entered into alliance with the Romans,² and had not been consigned to custody as slaves. Consequently they said they thought it right that the keys of the gates should be restored to them. [7] For good allies their loyalty was the strongest bond, and the Roman people and senate would be grateful to them only in case they remained in their friendship willingly and not under compulsion. [8] In reply to this the Roman commandant said that he had been placed at his post by his general and had received from him both the keys to the gates and the guarding of the citadel, to keep them, not at his own discretion nor that of the people of Henna, but of the man who had confided them to him. [9] To leave one's post was among the Romans a capital offence, and fathers had punished that crime with the death even of their own sons. The consul Marcellus was not far away; they should send legates to him who had the right to decide the matter. [10] But they said that they would not send them, and asserted that if they accomplished nothing by words, they would seek some means of recovering their freedom. [11] Upon that Pinarius said that, if they objected to sending to the consul, very well, let them at least give him an assembly of the people, that it might be known whether their demand was that of a few men or of the whole city. They agreed to an assembly on the next day.