this is a cutout from <a class="external free" href="https://commons.wikimedia.org/wiki/File:L-Oberlicht2.png">http://commons.wikimedia.org/wiki/File:L-Oberlicht2.png</a>. Construction to bring light in a cellar with prismatic glass tiles.
<a href="//commons.wikimedia.org/wiki/User:Sonty567" title="User:Sonty567">Sonty567</a>
1904
Lexikon der gesamten Technik (dictionary of technology) from 1904 by Otto Lueger