On page 598 of the 6th December 1912 issue of The Engineer we see a photograph of the newly built floating pontoon which was the fourth Galata Bridge of Constantinople. The accompanying article (p 605 Ibid) tells us that it was built - offsite in Gustavsburg - by the Maschinenfabriek Augsburg-Nürnberg AG.
It's the second pontoon bridge at that site, connecting Galata and Stamboul with 1542 feet of German Bridginess, and replaced the one built forty years earlier. Most of the Golden Horn traffic is diverted from another bridge, slightly awkwardly positioned, upstream. Construction began in the summer of 1910. It was fire-damaged in 1992 and replaced by a non-pontoony one.
Small passenger boats could travel under it, and a floating opening provided passage for others. The troubledness of the water refers to the situation at the time, what with the First Balkan War'n'all.