Caldera naval rectangular
The Marine Steam Engine von Richard Sennett,Henry J. Oram 1899
<a rel="nofollow" class="external free" href="https://books.google.de/books?id=oNhZIJBOiH4C">https://books.google.de/books?id=oNhZIJBOiH4C</a> pagina 61 <a rel="nofollow" class="external free" href="http://www.naval-history.net/WW0Book-Sennett-MarineSteamEngine.htm#1">http://www.naval-history.net/WW0Book-Sennett-MarineSteamEngine.htm#1</a>