Tactics Diagram

 The tactics diagram from the Greek maritime museum's website.
 


1) This shows the concept of the 'periplous'.
This means 'circumnavigation' and is, essentially, an outflanking manouvre at sea.

In this diagram it appears that the manouvre is almost identical to 4) and it also appears that the flanking ship is attacked. Both these similarities are false.

The periplous is executed under view of the flanking ship and it could respond. It is more likely the successful outflanking manoeuvre would proceed along the back of the enemy line and attack targets which had not observed it and had no space to respond.

2) This appears to show a 'rake' whereby a ships steers along the side of another and attampts to brake its oars and thereby cripple its manoeuvreability. Speed is essential for an oar rake to avoid giving the enemy a chance to ship their oars or turn away and to give enough energy to snap a large number of wooden oar-shafts. This diagram appears to show a violent turn as part of the manoeuvre. Turns reduce speed and are thus unlikely as part of a raking attempt.

There is little evidence that this was, in fact, a tactic. It is more liukley that it was an unintended result of a failed diekplous.

3) A 'conventional' ram attack. The attacker has managed to accelerate and turn into the beam of an unexpecting member of the enemy front line. The target has not responded and the attacker manages to hit his beam at an acute angle. A wider angle is better for a ram attack if space allows. If the target observed the attacker he would have turned his ram to meet the attacker head-on or backed water.

It is more likely that ramming was attempted at a better angle of attack than shown here and any collision such as this was a result of a failed or messy diekplous.

4) This appears to show the 'diekplous' or 'crossing' of the enemy line. The attacker rows through a gap and turns to attack an enemy from the rear.

The diagram appears to show the attacker hitting an enemy who is almost his counterpart in the lines. A ship must accelerate to shoot through any gap and a turn is unlikely to be made so tightly as to hit a ship lying opposite in th enemy line. If ships sit at circa one width apart for manoeuvre-room then a tight turn circa two ships length in diameter is not going to allow an attack on the opposite ship.

The manoeuvre of turning about to attack is known as the 'anastrophe'.

There is much discussion as to whether diekplous and periplous are tactics for single ships or groups of ships. There are examples where both are described. The point is the principle involved in the manoeuvre. Essentially they mean 'breakthrough' or 'outflanking', respectively.

My modified version of the same diagram.