<div class="description">
According to an article in International Marine Engineering, Volume 25 (available through Google Books) the jack was designed by W.F. Young, an employee at the Puget Sound Navy Yard to help construct ships more efficiently. The article includes diagrams of the tool and describes its uses.</div>
This file was contributed to Wikimedia Commons by <a href="https://en.wikipedia.org/wiki/en:Seattle_Public_Library" class="extiw" title="w:en:Seattle Public Library"><span title="public library system serving Seattle, Washington">Seattle Public Library</span></a> as part of a cooperation project. The donation was facilitated by the <a href="https://en.wikipedia.org/wiki/Digital_Public_Library_of_America" class="extiw" title="w:Digital Public Library of America">Digital Public Library of America</a>, via its partner Northwest Digital Heritage.<span style="text-align:left">
<ul><li><a rel="nofollow" class="external text" href="http://cdm16118.contentdm.oclc.org/cdm/ref/collection/p15015coll4/id/4636">Record in source catalog</a></li>
<li>DPLA identifier: <a rel="nofollow" class="external text" href="https://dp.la/item/41a81e62a43a867a7abc614ce3d03410">41a81e62a43a867a7abc614ce3d03410</a></li>
<li>Seattle Public Library identifier: spl_shp_41225</li></ul></span>