Sometime between 360 and 346 BC, a manual on how to survive a siege was written in ancient Greece. The text as we have it today is commonly attributed to a man named Aeneas, or rather Aeneas the ‘Tactician’ as he has become known.

The text is a wonderful smorgasbord of hints, tips, tricks, practical solutions and advice about preparing for, surviving and fighting back against the besieging of one’s city produced in an era when city-sieges were becoming more and more common.

Aeneas covers how to organise the city guards, how to prearrange signals, the importance of putting up notices to deter potential traitors, how to prevent tampering with the bars and bolts of city gates, how to undertake secret offensives at night against besiegers, how to deal with mass panics in the city and how to set fire to the enemies’ machinery and put out fires in the city amongst a myriad of other things.

My two favourites, however, are tips in a section entitled “Ruses” and another on “Secret Messages”. For ruses, he advises the digging of a deep trench on the inside of the main city gate.

The besieged city sends a small patrol out to skirmish with the enemy, who subsequently turn tail and flee back inside the gates.

The enemy will hopefully follow and fall into the deep trench, where they can be killed off at will.

Secret Messages contains even more artful and cunning ideas. Secret messages can be concealed on thin pieces of metal hidden in the lining of a shoe, or they can be written on leaves tied into dressings over people’s wounds.

A message can be written on a piece of metal then rolled and worn by a woman as an earring. Messages can be sent by carefully placing tiny dots underneath certain letters within a bigger text, which subsequently spell out the message. Perhaps the best however, is this.

Take a cow’s bladder and blow it up. Then write your message on the outer skin of the bladder using a mixture of glue and ink.

Then deflate the bladder and stuff it inside a small flask with the opening of the bladder level with the flask opening.

Fill the inside of the bladder (and thus the flask) with oil till the bladder skin is pressed against the material of the flask.

The bladder will be invisible as will the message. All the recipient has to do is pull out the bladder, inflate it again and the message will be readable! Ingenious! Beats text messaging any day!

Michael C Scott is a Research Fellow and lecturer at the Faculty of Classics, Cambridge University. He is also the author of ‘From Democrats to Kings’ and the monogram ‘Delphi and Olympia’. For more information go to: www.michaelcscott.com