Acknowledgements
The author acknowledges the team (Carlos Gomes, Carlos Trindade, João Pedro Freire, Jorge Russo, Luísa Tavares, Manuel Leotte, Nuno Sousa, Paulo Carmo, Paulo Correia, Paulo Costa, Pedro Encarnação, Pedro Ivo Arriegas, and guest photographer, Armando Ribeiro), members of XploraSub and In Silence dive groups. All were volunteers, paid all their own expenses and spent weekends and holidays committed to the project, with disadvantages for their families. The author also would like to acknowledge the local diving industry that provided the team with exceptional quality services and safe dives. A special thanks to John Riley, sadly deceased, for sharing his knowledge of steam technology. And finally to Tiago Fraga for the revising this text.