The successors of Alexander the Great and their descendants built fleets consisting of many ships and achieved the construction of colossal ships such as the tessarakonteres(40-rowed). They were truly floating fortresses, reminiscent of modern battleships and aircraft carriers.

The tessarakonteres carried a total crew of 6,000 men, roughly the size of a modern aircraft carrier. The name "forty" does not refer to the number of oars, but to the number of oarsmen on each rowing line that propelled it.

The distribution of the oarsmen lines seems to have been quite functional until the "sixteen rowed" mentioned by the ancient sources. Perseus, the last king of Macedonia, had a "sixteen rowed" as his flagship.

However, the ancient sources mention a tessarakonteres, the one from Ptolemy that had 4,000 oarsmen. The attempt to interpret this term, which corresponds to 40 lines of rowers, still raises questions among scientists.

There are various explanations for the distribution of the oarsmen of this huge ship, but the most important remains the one proposed by L. Casson, who assumed that it was a catamaran type ship. In his opinion, the tessarakonteres(40-rowed) was in fact made up of two eikoseres(20-rowed) which were firmly connected by a common deck.

Such cases are known in the Hellenistic times, e.g. during the siege of Syracuse by the Romans (212 BC): they connected penteres (5-rowed) in the same way in order to place the "Helepolis" (tower-like siege structures) on the common deck, to occupy the city's coastal walls.

According to Casson, each of the two eikoseres(20 rowed) that make up the tessarakonteres(40-rowed) would have 2,000 rowers, out of 1,000 on each side. Casson's view of tessarakonteres as a catamaran may seem paradoxical, but it makes the most sense from other assumptions. For example, a 19th-century philologist estimated that the quadruped had 40 horizontal rows of oars with only one oarsman in each row.

The quadruped was an expensive boat, cumbersome and extremely difficult to navigate. It seems, however, that its builders were aware of these disadvantages before they started building the boat. Ptolemy Philopator, the richest monarch of his time, would have no financial problems to obtain it. If you add the seamen (deck service, etc.) who were needed to navigate the ship, the officers, the military guard and the rest of the personnel, the total crew (together with the 4,000 rowers) reached 6,000 men, for example, those who owned a modern aircraft carrier. The only advantages of the quadruped were its size and its deck. . In addition, its deck, when used in military operations, could accommodate catapults and catapults of colossal size, as well as a large number of marines.

Gradually, such colossal warships were abandoned by the naval forces of the Hellenistic era because of the high maintenance costs and the difficulty of navigating them. The only ones that were really easy to operate were the four, the five and the six, and less the seven, the eight and the ten.