Yenikapı shipwrecks made a unique contribution to our knowledge of ship building technology and development. Research carried out on the shipwrecks by Istanbul University’s ship experts reveals, from traditional shell based to skeleton based building methods and a transition period that is mixed building technique that contains both periods’ features. The researches established the usage of mortise-and-tenon joints which attach plankings that from the shell in some ships which were thought to be shell based; and the usage of coaks which attach plankings in some ships are transition period features. There aren’t any edge joint members on the planking in the third group of ships which are thought to be skeleton based. Different building methods were used in some ships dating back to the same period which points out local differences and the fact that the transition process is not linear. Without a doubt, the progress of scientific research about Yenikapı Shipwrecks will contribute greatly to the discussions about this process and reveal many unknown technical details.
According to the first results of the researches, it was understood that YK34 and YK35 shipwrecks’ hull plankings were attached with wooden pegged mortise-and-tenon joints. In YK 22 shipwreck it was determined that the plankings were joint together with unpegged mortise-and-tenon joints.
At the Yenikapı excavation area planking of shipwrecks that made with coaks are the majority. YK 3, YK 6, YK 7, YK 8, YK 9, YK 12, YK 13, YK 15, YK 16, YK 18 and YK 20 shipwrecks were thought to be built with the transition period mixed method.
Three shipwrecks were found without planking at the Yenikapı excavation area. The usage of skeleton based building method observed in YK 17, YK 27 and YK 29 shipwrecks.
Floating Fortresses of Byzantine Empire: Dromons
The most important warship of the Byzantine Era is the light and fast vessel dromon which can be in lots of different shapes and sizes. In these ships there are two or three decks with two or three mast and they can be up to 55 meters long and 6 meters wide. The ships carry people in different quantities according to their type and size. Some of these can carry 100, 200 even 300 men and some of these men are marines supported by rowers at war. Each dromon is equipped with a xylokastron(wooden tower) which is situated around the main mast and this tower is where soldiers throw their arrows, pieces of metal or rocks.
Greek Fire: Winning with Fire
The most important weapon of the Byzantines was “Greek Fire” or “liquid fire” which played a decisive role in all the naval battles. It’s a substance made according to prescription by a Greek engineer Kallinikos who lived in Helioupolis of Syria in the 7th century. The formula made of sulphur, nitrogen, naphtha and other substances kept burning above water which spread fear in their enemies. This chemical component was kept as a state secret. Emperors put emphasis on the secrecy of the formula and said that it’s not supposed to be known even by allies. Liquid fire was kept inside storages in the capital or other strategic places. The ingredients were kept as a secret for several centuries until it was discovored by the Arabs.