All these things were done with the utmost secrecy, and so cunning and adroit were the conspirators in forming and executing their plots, that Caesar seems to have had no knowledge of the measures which his enemies were taking, until he suddenly heard that the main body of Ptolemy’s army was approaching the city, at least twenty thousand strong.  In the mean time, however, the forces which he had sent for from Syria had not arrived, and no alternative was left but to defend the capital and himself as well as he could with the very small force which he had at his disposal.

He determined, however, first, to try the effect of orders sent out in Ptolemy’s name to forbid the approach of the army to the city.  Two officers were accordingly intrusted with these orders, and sent out to communicate them to Achillas.  The names of these officers were Dioscorides and Serapion.

It shows in a very striking point of view to what an incredible exaltation the authority and consequence of a sovereign king rose in those ancient days, in the minds of men, that Achillas, at the moment when these men made their appearance in the camp, bearing evidently some command from Ptolemy in the city, considered it more prudent to kill them at once, without hearing their message, rather than to allow the orders to be delivered and then take the responsibility of disobeying them.  If he could succeed in marching to Alexandria and in taking possession of the city, and then in expelling Caesar and Cleopatra and restoring Ptolemy to the exclusive possession of the throne, he knew very well that the king would rejoice in the result, and would overlook all irregularities on his part in the means by which he had accomplished it, short of absolute disobedience of a known command.  Whatever might be the commands that these messengers were bringing him, he supposed that they doubtless originated, not in Ptolemy’s own free will, but that they were dictated by the authority of Caesar.  Still, they would be commands coming in Ptolemy’s name, and the universal experience of officers serving under the military despots of those ancient days showed that, rather than to take the responsibility of directly disobeying a royal order once received, it was safer to avoid receiving it by murdering the messengers.

Achillas therefore directed the officers to be seized and slain.  They were accordingly taken off and speared by the soldiers, and then the bodies were borne away.  The soldiers, however, it was found, had not done their work effectually.  There was no interest for them in such a cold-blooded assassination, and perhaps something like a sentiment of compassion restrained their hands.  At any rate, though both the men were desperately wounded, one only died.  The other lived and recovered.