<p>From "The Ohio River" (1935), p. 208.
(updated to 1934)
</p><p>The navigable pass was made up of Chanoine wickets which when upright would maintain the water level in the pool above the dam and when lowered would allow water to flow through the pass so boats could travel through the Falls during periods of high water, thus bypassing the Portland Canal and Locks 41 (later renamed McAlpine Locks).
</p><p>Ohio River miles 605-607 (based on modern charts)
</p>
Louisville, Kentucky on left bank; Clarksville, Indiana on right bank
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/70020260@N04">William Alden</a> from Louisville, Kentucky, USA
CC BY-SA 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/bill_alden/6792563873/">99c091 supplement 2: Lock and Dam 41 chart (1934)</a>