1521020 patent of 1923
James W. McGhee
1924-12-30
<ul><li><span><a rel="nofollow" class="external text" href="https://patents.google.com/patent/US1521020">U.S. Patent 1,521,020</a></span> <a rel="nofollow" class="external autonumber" href="http://www.google.com/patents/about?id=me5HAAAAEBAJ&amp;dq=1521030">[1]</a></li>
<li>Transfered from <a class="external text" href="https://en.wikipedia.org">en.wikipedia</a></li></ul>