1918 magazine advertisement for <a href="https://en.wikipedia.org/wiki/Lufkin_(brand)" class="extiw" title="w:Lufkin (brand)">Lufkin brand</a> rulers.
Unknown author<span style="display: none;">Unknown author</span>
Original photo dated <a href="https://en.wikipedia.org/wiki/1918" class="extiw" title="w:1918">1918</a>
Google Books - <a rel="nofollow" class="external text" href="https://books.google.com/books?id=MO_NAAAAMAAJ">Manual Training Magazine, March 1918, Volume 19,  xxiii</a>