An animated depiction of a bicylinder <a href="https://en.wikipedia.org/wiki/en:Steinmetz_solid" class="extiw" title="w:en:Steinmetz solid">w:en:Steinmetz solid</a>
<a href="//commons.wikimedia.org/w/index.php?title=User:Van_helsing&amp;action=edit&amp;redlink=1" class="new" title="User:Van helsing (page does not exist)">Van helsing</a>
CC BY 2.5
self-made largely based on <a rel="nofollow" class="external text" href="http://mathworld.wolfram.com/SteinmetzSolid.html">wolfram’s mathworld Steinmetz solid page</a>