The Invention of Rocking W-irons?

In the early days of the SSMRS a series of notebooks were circulated between members where they discussed their latest achievements and ideas. One of these notebooks contained the page below dated 17/5/55. I think this is the earliest use of rocking W-Irons to achieve a three-point suspension on a wagon in the UK. At the time Stan Garlick was developing the alternative "rocking solebar method".