![CC-P-0113.T.jpg](http://iiif.mused.com/iyoGAttvl-cc-p-0113-t.jpg/full/1000,/0/default.jpg)
A sideview engraving of British Captain John Schank's first boat with a sliding keel. While stationed at Boston, MA in 1774, Schank built the first vessel fitted with a "sliding keel", as he termed it. It worked vertically through a trunk or well, and the keel of the boat.