The Shelton Test is sometimes called "Houdini's last trick", although we now know he repeated the test at the Worcester YMCA and did a non-submerged version at Summerfield's department store. Still, it was certainly Houdini's last wildly covered publicity stunt, and anticipated the public endurance tests of modern magicians like David Blaine.
|The New York American, August 6, 1926|
A wonderful first hand account of test written by Houdini himself can be read at the blog Letters of Note. The Hotel Shelton is today the Marriott New York East Side, but the hotel restaurant still bares the name "Shelton Grill." The pool where Houdini performed his famous test was filled in in the early 2000s.